A method for testing quality of an ophthalmic lens

The present invention relates to a method and an arrangement for controlling the quality of a vision enhancing lens. The method involves illuminating a vision enhancement lens, particularly a contact lens, generating an image of the enhancement lens to be examined and classifying the enhancement lens according to image quality. The arrangement of the present invention comprises a support for receiving a vision enhancement lens, a light source and an imaging component for generating an image of the vision enhancer based on a beam of light emanating from the light source and passing through the support and then the vision enhancement lens. The invention will now be described, first and foremost, with reference to contact lenses, but it will of course also be useful in the manufacture of vision enhancing lenses and other lenses of a similar design.

In the manufacture of vision-enhancing lenses and, above all, contact lenses, a very high dimensional accuracy and a desired surface fineness must be sought. In spite of all the measures, there may be malfunctions in the manufacturing process that result in the formation of an inaccurate part of the resulting contact lens. These vision-enhancing lenses are screened by quality control, i.e., before being transmitted to the user, the vision-enhancing lenses are tested for suitability for their intended use.

The quality of the vision enhancement lenses is controlled by prior art methods which are considered manual, whereby the completed vision enhancement lenses are individually placed in recesses of a plurality of support substrates, and the lenses are then placed in a group control position where they are illuminated one by one. The light beam used for illumination is focused on the canopy to obtain the image of a vision enhancing lens. The quality control person examines this image and looks for irregularities. If it detects an irregularity or 25 fissures that render the vision correction lens unsuitable for its intended use, it shall be removed from the test system or otherwise identified so that it can be subsequently filtered and not passed on to the user.

This method of control, also known as manual control, is generally believed to be sufficiently effective and reliable. However, this efficiency is not always acceptable with increasing volumes and needs to be improved. Above all, the relative slowness and costly nature of the system is a drawback. The reason for this is that the person performing the investigation must view the image created on the screen and review the whole image. This is time consuming 35, so the examination of the lens is relatively costly and must be performed by experienced persons.

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-3- Another problem with the known and manual control system is that the subject's decision to accept or reject the lens is quite subjective, the factors involved here vary from person to person, and if so, the same person. he evaluates a vision enhancement lens under different conditions in different ways. Evaluation criteria may also change over time. A typical mistake is that the subject rejects the lens in terms of quality, although the usable or inverse case may occur, and the person will consider the lens of poor quality to be of acceptable quality.

It follows from the foregoing that there is a need for a procedure and arrangement for controlling the quality of vision-enhancing lenses, particularly contact lenses, more quickly and reliably than ever before, under the same conditions.

It has been recognized that at the end of the manufacturing process, the corrective lens, in particular the contact lens, must be embedded in an electronic image analysis system which, in conjunction with an electronic data processing system, is capable of quality control and detection of irregularities, fractures, defects.

Accordingly, our task is to provide a method and arrangement in which quality control can be performed at high speed, in an automated manner, free from subjective errors.

As a solution to this task, we have developed a method and arrangement for controlling the quality of a vision enhancing lens based on recognition.

In the embodiment of the present invention, a vision enhancing lens, in particular a contact lens, is illuminated with a beam of light, the beam under examination produces an image to be examined of the vision correction lens and classifies the image enhancer lens we produce it in a pixel field, assigning to each pixel data corresponding to the intensity of the light beam incident on each pixel and determining the position of the pixel, and classifying by analyzing the pixel data according to a predetermined program to satisfy one or more selected conditions.

Conventionally, the contact lenses are formed as a structure consisting of an inner and outer optical zone substantially delimited by a circular line. In examining this, it is particularly advantageous to produce an image corresponding to the outer and inner edges of the ring designated by the light beam and the inner and outer optical zones, and then to obtain the pixels containing the pixels.

And selecting a center and a radius to define a first circle substantially coinciding with the circular contour of the inner optical zone, a second circle defining a center and radius of the inner optical zone similar to the first circle, and determining the distance between the centers of the first and second circle. , comparing the determined distance with a predetermined value and determining the centered nature of the inner and outer optical zones and the contact lens therewith. This is preferably accomplished by identifying a first pixel group having at least three pixels in the image of the outer edge of the inner optical zone in determining the center and radius of the first circle, and then centering the circle of the first pixel on the circumference determine its radius, and determining the center and radius of the second circle by identifying a second group of pixels having at least three pixels in the image from the outer edge of the outer optical zone, and calculating the center and radius of the circle with the perimeter superimposed. In this case, it is advantageous to select three first and three second pixels from the first and second pixel groups, selecting a set of pixels that define a line segment , and then checking the illumination level of the pixels for each series, and level is divided into better and less illuminated pixels.

The method of the present invention is generally used to control a vision enhancement lens that produces an image of an outline on a pixel field, preferably by controlling the light beam to form pixels from the outer edge of the vision lens, particularly the contact lens, and then at least one pixel position identified, identifying the gaps between pixels in the image carrying information about the outer edge and the extras that are associated with the outer edge, determining its width for each identified gap, comparing the width with a predetermined value, and classifying the vision enhancement lens as flawed when the predetermined value is exceeded; determining the area occupied by each of the identified complementary elements that can be assigned to the outer edge of the vision enhancement lens, comparing this area with a predetermined value, and evaluating the vision enhancer lens as flawed if the area is larger than the predetermined value. This procedure is generally accomplished by selecting a center point on the outer edge of the vision enhancement lens to define slits and discrete pixels, and defining a first circle whose outline generally coincides with the outer edge of the vision enhancement lens, and P 93 03408

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-5 for each selected pixel, the distance between it and the outline is selected, the vision enhancement lens is considered slit if, for a given number of successive pixels in the image of the enhancement lens, the pixel is within the outline and the distance between the pixel and the outline higher than a given value, and finally considered to have a vision enhancement lens, when, for a given number of consecutive pixels in an image on the outer edge of the vision enhancement lens, the pixel is located outside the outline and the distance between the pixel and the outline is greater than a specified distance.

In determining the width of a slot, it is convenient to scan the outline of the first pixel within the slot for a pixel that identifies its end, and then look for a pixel formed radially inward and outward of the outline of the vision enhancement lens.

Another preferred embodiment of the method of the present invention is to provide a pixel image of the outer edge of the vision lens by controlling the light beam by controlling the light beam, and then identifying at least one of the pixels of the outer edge image of the vision lens. , we open the gaps between the pixels that carry information on the outer edge of the image, highlighting the information on the revealed slots with a high value attributed to selected pixels in or adjacent to the slit. This is preferably accomplished by selecting, for each of the identified slots, a first pixel that identifies the beginning of the slot and a second one that defines the end of the slot, and then the pixels in the line segment between the first and second pixels, and we attach high values ​​to the pixels of the gap revealed in the outer edge of the lens.

The method of the present invention may conveniently be performed by visualizing pixels on the exterior edge of the vision enhancement lens, in particular contact lenses, and then analyzing the data by centering on the outer edge of the vision enhancer lens and centering on the set of pixels. defining a circle whose perimeter generally coincides with the outer edge of the lens of vision, selecting at least one pixel from the outer contour of the vision lens in the image, then selecting a different pixel within a distance from the outer edge of the vision lens for each selected pixel, taking a first vector between the selected and the other pixel; taking a second vector between the pixel and the center, forming a vector product of the first and second vectors, comparing the vector product to a predetermined value and not correcting the vision lens P 93 03408

-6 is accepted as good quality if the vector product is greater than the specified value.

It is also very convenient to implement the method of the invention, by inspecting the outer edges of the vision lens with pixels in the control of the visual enhancement lens, in particular the contact lens, and then identifying the pixels complementing the outer edge of the vision enhancer lens. then, the information about the identified additional elements is highlighted by the large value assigned to the selected pixels adjacent to the additional element. In this process, selecting the first pixel defining the beginning of the discovered accessory element and the second defining the end of the discovered accessory element for each of the discovered accessory elements, and then assigning a high value to the pixels in the linear segment between the first and second pixels. attribute, and do the same for the pixel in the image of the auxiliary element.

A further embodiment of the above-described method of relying on the revealed accessory elements is obtained by providing a first pixel on the front face of the accessory of each accessory accessory in the image of the enhancement lens when facing the accessory. on the edge, we select a second 20 pixels at a distance from the first pixel, and identify a third pixel on the back of the accessory, selecting a fourth pixel at a distance from the third pixel at the back of the vision enhancer lens, forming a first line segment between the first and second pixels, a second line segment between the third and fourth pixels, and the first and second line segments we assign high values ​​to the pixels in the segment 25, preferably with the accessory lens enhancement element, defining a first zone comprising a first set of pixels from the outer edge of the vision enhancement lens and a first line segment, followed by a second zone containing a second group of pixels, followed by an additional element, an outer edge image of the enhancement lens and a second line segment; attributed to pixels in the first and second zones.

Yet another advantageous embodiment of the method of the invention is obtained by selecting areas containing high value pixels in the set of pixels in the analysis of pixel data and highlighting the selected areas by assigning different values ​​to adjacent pixels. This is preferably done by visualizing the outer edge of the vision lens with pixels while controlling the beam of vision using an outline, and then analyzing the data from the outer edge of the vision lens aP 93 03408 ········································· ···· «··· • ·« ···· ··· ··· ··· ···

-7 a set of pixels in a fixed image fragment is selected and small values ​​are assigned to the pixels in the set, and in the data analysis, adjacent groups of pixels characterized by high values ​​are selected.

The arrangement of the object of the present invention comprises a vision component comprising a vision enhancement lens, in particular a contact lens support, a light source, and an imaging device for forming an image enhancer lens according to the present invention, image processing unit, comprising a pixel10 field formed from light-sensitive elements as pixels, and the imaging unit is configured in advance to direct the beam of light into the pixel field, and the light-sensitive elements in the pixel field are connected to an electronic system for analyzing the intensity of light they perceive; wherein the electronic system is configured to compare visual quality lens quality indicators with a predetermined set of conditions.

The arrangement according to the invention is very useful in examining a vision-enhancing lens consisting of an inner and outer optical zone delimited by a substantially circular line, whereby the imaging unit is preferably formed to form an image from the edge of the inner and outer optical zones. center and radius based on photosensitive elements in a pixel field, to define a first circle substantially coincident with the circular contour of the inner optical zone and a second circle substantially coincident with the circular contour of the outer optical zone, and then determining the distance between the centers of the first and second circles and comparing the determined distance with a predetermined value is adapted to determine whether the contact lens is centered or decentralized.

An embodiment of the arrangement of the present invention for controlling an outline enhanced vision lens, especially a contact lens, and wherein the imaging unit is provided with a means for forming an image of the outer edge of the vision enhancer lens, enables effective quality control to be performed effectively. and an electronic system for identifying gaps between the photosensitive elements carrying the outer edge information and the peripheral components of the image on the outer edge of the vision enhancement lens to determine and compare the width of the gaps with a predetermined value, furthermore, to determine the size and compare the size to a predetermined value in the image, for the auxiliary elements at the outer edge of the vision enhancement, and for both comparisons, a size or width

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Exceeding a predetermined value, the visual enhancement lens is configured to disassemble the lens due to rupture, and optionally, the electronic system is configured to assign a large value to pixels adjacent to the pixels defined by the photosensitive elements of the slots and auxiliary elements.

Effective and fast quality control is also provided by the advantageous implementation of the arrangement of the invention, wherein the imaging unit is adapted to produce an image of the outer contour for testing a substantially circular outer contour lens, in particular a contact lens, and an electronic system for selecting, based on the photosensitive elements in the pixel field, a circle substantially coinciding with the outer circular circumference and centering the circle, selecting at least one of the photosensitive elements in the image from the outer edge of the vision enhancement lens; edge image to define another pixel forming a photosensitive element at a distance from the selected one, a first vector between the selected and the other pixel, a second vector between the selected pixel and the center, and then forming a vector product of the two vectors and discarding the vision enhancement lens if the vector product is below a predetermined value; located in selected zones of the pixel field, is adapted to select high-sensitivity photosensitive elements and to assign high value to the pixels forming pixels adjacent to the selected zones in the photosensitive elements.

Also preferred is an embodiment of the arrangement of the invention for examining a vision-enhancing lens, particularly a contact lens, characterized by a substantially circular outer contour, wherein the imaging unit is configured to produce an image from the outer contour and the electronic system in the pixel field to identify the photosensitive elements of the edge image and to the photosensitive elements identified, thus, it is adapted to assign small values ​​to the image of the outer edge of the vision enhancing lens.

The data processing is facilitated by a preferred embodiment of the arrangement according to the invention, wherein the electronic system is adapted to identify coherent adjacent groups of photosensitive elements of high value in the pixel field.

The method and arrangement of the present invention, by analyzing an imaging photosensitive element, i.e. pixels, arranged in a manner known per se from a beam of light passing through a vision enhancer lens, the vision enhancer lens is well automated.

-9 provides a manageable quality control. Quality control is generally performed by examining the continuity or uniformity of outlines in the form of a vision enhancing lens, whereby pixels defining a discontinuity or a non-uniform outline due to the presence of an auxiliary element are preferably distinguished by assigning small or large values ​​to them. The outline is then compared with a predetermined intima, and the decision to accept or reject the vision enhancing lens is deduced from the result of the comparison.

The invention will now be further exemplified. with reference to the accompanying drawings. In the drawing it is

First Figure 4A is a schematic diagram of an arrangement for automatically controlling the quality of the vision enhancing lenses of the present invention;

Second Figure 1 is a plan view of a vision enhancement lens examined in the arrangement of Figure 1,

Third Figure 2 is a side view of the contact lens shown in Figure 2;

3A. Fig. 2A is an enlarged section of the edge of the contact lens shown in Figs.

4th Figure 1 is a plan view of the contact lens transfer unit used in the arrangement of Figure 1;

5th Figure 1 is a plan view of the lens carrier used in the arrangement of Figure 1 and used in the sub-assembly shown in Figure 4;

6th Figure 5 is a side view of the lens carrier shown in Figure 5;

7th Figure 4A is a schematic diagram illustrating the principles of dark field illumination technique;

8th Figure 1 is a more detailed illustration of the illumination and imaging components formed in the arrangement of Figure 1;

9th Figure 1A shows the feasibility of implementing a portion of the pixel field used in the imaging unit;

10th Figures 2 and 3 are a view of the pixel field in the arrangement of Figure 1,

Figure A shows a preferred embodiment of the optical structure of the illuminating and imaging unit 30 created in the arrangement of the invention,

IIB. another preferred embodiment of the optical structure of the illuminating and imaging unit created in the arrangement according to the invention,

IIC. FIG. 4A is a further preferred embodiment of an optical structure of an illuminating and imaging unit in the arrangement of the present invention;

12A. Figure 1 is a block diagram of the control unit used in the arrangement of Figure 1;

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-ΙΟΙ 2Β. Figure 1 is a graph of events occurring during the operation of the transport, illumination, and imaging assembly used in the arrangement of Figure 1;

13th Figure 1 is a block diagram of the data processing performed in the image processing unit used in the arrangement of Figure 1;

14th Figure 1 is a diagram illustrating the relationship between the basic components used in a preferred embodiment of the data processing performed in the arrangement of Figure 1;

15th Figure 1A is a possible variation of an image of a pixel field vision correction lens used in the arrangement of Figure 1;

16A. Figure 3B is a flowchart of the test procedure for verifying the lens enhancement, a

16B. Figure 16A. 17A is another embodiment of the flowchart of FIG. Figure 3A is another possible version of a pixel field vision correction lens, a

17B. 17A. 17C is an enlarged detail of the annular portion of the image shown in FIG. 17B. is a graph of the intensity observed for pixels along the line segment shown in FIG.

17D. 17A. FIG. 1A is a possible course of the first graph obtained by first processing the illuminance measured at pixels detected by identifying the ring boundaries present in the image of FIG.

17E. 17A. FIG. 2A is a possible course of the second graph obtained from the second processing of the illuminance measured at the pixels detected by identifying the ring boundaries present in FIG.

17F. 17A. FIG. 4A is a possible course of the graph obtained from the third processing of the illuminance measured at the pixels detected by identifying the ring boundaries present in FIG.

17G. 17A. Fig. 4A is a possible course of the graph obtained from the fourth processing of the illuminance measured at the pixels detected by identifying the ring boundaries present in the image shown in FIG.

17H. 17A. Figure 5A is a plot of the graph obtained from the fifth processing of the illuminance measured at the pixels detected during the identification of the ring boundaries in the image shown in FIG.

171st 17A. Fig. 6A is a possible course of the graph obtained from the sixth processing of the illuminance measured at the pixels detected during the identification of the ring boundary in the image shown in FIG.

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- 11 17J. 17A. FIG. 6A is the result of adjusting the illumination intensities obtained by processing pixels along the edges of the ring in FIG.

18th a flowchart of a possible implementation of a method for processing the initial illumination values ​​determined for pixels selected in the pixel field,

19A. the result of the first step of the masking operation performed on the values ​​assigned to the fields selected in the pixel field,

19B. the result of the second step of the masking operation performed on the values ​​assigned to the fields selected in the pixel field,

19C. the result of the third step of the masking operation performed on the values ​​assigned to the fields selected in the pixel field,

20th Figure 21A is a flowchart of a preferred embodiment of the masking method; FIG. 4A is a list of initial steps in a preferred embodiment of a data processing method defined as a rubber band algorithm in FIG.

21B. Figure 21A is a flowchart of the final steps of the procedure of the initial steps of Figure 21A, a

22nd Fig. 4A is a flowchart of a subroutine for identifying a first pixel in a wind based on a line mapping image;

23rd A flowchart illustrating an important detail of the rubber band algorithm, FIG

24th a flowchart of a preferred embodiment of a bridging subroutine for defining a gap in the outer contour of the vision enhancing lens, FIG.

25A. Figure 3A is a detail of the outer contour of the image of the vision enhancement lens and one of the options for positioning the various pixels associated with the image being examined;

25B. 25A. FIG. 4A is another proposed alternative for bridging the various pixels to be examined belonging to a slit in the outer contour of the vision enhancement lens;

25C. 25A. FIG. 1A is a first step in bridging the various pixels of an auxiliary element to be examined in the outer contour of the vision enhancement lens;

25D. 25A. FIG. 2A is a second step in bridging the various pixels to be examined in an outer contour of an image enhancement lens;

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- 12 25Ε. 25A. FIG. 3 is a third step in bridging various pixels of an auxiliary element to be examined in the outer contour of the vision enhancement lens;

26th a flowchart of a preferred embodiment of a subroutine used to bypass an external edge in the image of a vision enhancement lens when bridging an additional element,

27th Figure 23 is a flow chart of a program executed after completion of data processing with the flowchart shown in Figure 23;

28th a flowchart of a program for executing another important step of the rubber band algorithm, a

29th Figure 3A shows a portion of the outer edge delimiting the image of the vision enhancement lens, illustrating some of the vectors used in the second basic step of the rubber band algorithm,

30th a flowchart of steps performed in the third major step of the rubber band algorithm, a

31st Figure 1A is an effect obtained by performing two steps in the algorithm of Figure 30, a

32nd Figure 3B is another effect obtained by performing two steps in the algorithm of Figure 30, a

33rd Figure 3A is a detail of the outer edge of the ring formed from a vision enhancement lens, showing some bridges added to the edge;

34A. Figure 5A shows the matrix resulting from the processing performed on the intensity data obtained in the pixel field,

34B. Figure 34A. The matrix obtained from the MAX operation on the processed data of FIG

34C. Figure 34A. A matrix obtained as a result of a PMAX operation on the processed data of FIG

34D. Figure 34A. a matrix resulting from a MIN operation on the processed data of FIG

34E. Figure 34A. A matrix obtained as a result of a PMIN operation on the processed data of FIG

35th a flowchart of a preferred processing method for highlighting or marking possible defects at the edge of the lens on data received from pixels selected in the pixel field,

36th Figure 35 is a view obtained as a result of performing the process of the flowchart of Figure 35;

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37th Figure 2A is a flow chart of a second masking method performed on pixel data defining an image of a vision enhancer;

38A. Figure 3B is a possible version of the image obtained by the method shown in Figure 37, a

38B. Figure 37 is an image obtained after covering the image obtained by the method of Figure 37 with a circular mask;

38C. Fig. 38B is a view taken from the method of Fig. 37; Figure 4a

39th Fig. 3A is a flowchart of another method of extracting data from any additional defect detecting pixels that may be present in the examined enhancement lens;

40A. Figure 3B is a representation of the results obtained by performing the procedure defined by the flowchart of Figure 39;

40B. Figure 40A. FIG

40C. Figure 40A. 40B. FIG

40D. Figure 40C. Figure 5A is a representation of the filled fields obtained by cleaning the shape of Fig. a

41A. Figure 1B is a first flowchart of a preferred flowchart of a method of identifying possible ruptures and similar defects in the subject's vision enhancement lens,

41B. FIG. 41 is a continuation and completion of the flow chart of FIG. 41, and FIG

42nd Figure 4A shows various types of possible defects in the lens of vision.

In accordance with the present invention, there is provided a method and arrangement for controlling the quality of vision enhancing lenses and, in particular, contact lenses. According to the present invention, a quality control system 10 is proposed which is preferably constructed according to the block diagram of FIG. The main components of the quality control system 10 are the transport unit 12, the lighting unit 14, the imaging unit 16 and the image processing unit 20. In the implementation of the quality control system 10, it is particularly advantageous for the transport unit 12 to be provided with a lens support 22 24, the details of which are shown in Figure 4. In the illuminating assembly 14 shown here, the housing 26 comprises light sources 30 and mirrors 32 and 34 for controlling the light emitted by the latter. Behind the mirror 34 is located the imaging unit 16, which has a camera 36, ​​a stop member 40 forming a cover element and an illuminating len35 system 42. The components of the imaging component 16 are illustrated in more detail in Figure 8, where the camera 36 is provided with a housing 44 including a pixel field 46 and an aperture 50 at its inlet. Figure 8 otherwise illustrates the illumination portion 14 of the illuminator

- Includes 14 units. The illumination lens system 42 is received by a tube 52 formed by first and second beam forming lenses 54 and a plurality of baffles 60 disposed inside. As shown in Figure 1, the image processing unit 20 includes a preprocessing system 62, a processor 64 and a data input element such as a keyboard 66. Preferably, the imaging unit 20 is provided with a storage 70, a video monitor 72, a connector 74, and a printer 76.

The basic function of the conveying unit 12 is to move a particular set of vision enhancement lenses 80 in a predetermined path such that each of the vision enhancement lenses 80 is always in the path of the light beam generated by the illuminating assembly 14. Figure 1 illustrates an arrangement in which a single vision enhancement lens 80 is located in the quality control position. The imaging unit 16 generates a sequence of signals relating to the details of the image of the enhancement lens 80 transmitted by the light beam passing through it. These signals are transmitted from the imaging unit 16 to the imaging unit 20, whereby processing the data obtained from the imaging unit 16 identifies a predetermined program of which vision enhancement lens 80 meets the requirements of quality control. In a preferred embodiment of the imaging unit 20, as described below, operations can be performed that determine whether or not the lens being tested is suitable for its intended use.

The quality control system 10, i.e. the arrangement according to the invention, is well suited for determining the quality of vision enhancement lenses 80 in different classes of vision enhancement lenses 80, which may be substantially different in size and shape. The quality control system 10 is primarily intended to test vision-enhancing lenses 80 which are formed as contact lenses 84. Figures 2 and 3 illustrate a possible design of contact lenses 84. In accordance with conventional construction, the contact lens 84 comprises an inner optical zone 84a and an outer optical zone 84b between which is a ring 84c. The thickness of the contact lens 84 is substantially the same, but as shown in FIG. As shown in FIG. 6A, the thickness of the ring 84c gradually decreases as it radiates outwardly and defines the edge of the contact lens 84 with the smallest portion of the ring 84c. This edge is bounded by front 86 and rear 90 (Fig. 3A), and its radial size is an important feature of contact lens 84.

Figure 4 illustrates details of a possible embodiment of the transport assembly 12, showing the mutual location of the lens carrier 22 and the support 24. In the support 24, the lens carrier 22, to which the first and second stepping motors 94 and 96 are attached, is received by a transfer table 92, the transfer table 92 itself being provided with a base plate 100 and frames 102 and 104.

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The lens carrier 22 is configured so that a plurality of batches of vision enhancement lenses 80, and in particular contact lenses 84, are conveyed therein. Figures 5 and 6 show some details of the lens carrier 22. In these figures, it can be clearly seen that the base of the lens carrier 22 is a rectangular plate 106 in which the receiving apertures 110 are formed and into which the contact lenses 84 under examination are placed. The receiving openings 110 are preferably bounded by frustoconical side walls 110a and hemispherical bottom walls 110b, which are joined together in their material and extend downwardly from the rectangular plate 106. For each of the receiving apertures 110, the radius of curvature of the hemispherical bottom wall 110b is preferably constant, approximately 10% greater than the radius of curvature of the contact lenses 84, and the diameter of the hemispherical bottom wall 110b is larger than the diameter of the contact lens 84. Preferably, the truncated conical side wall 110a engages the rectangular plate 106 with an angle of inclination of about 20 °, the receiving opening 110 and the hemispherical bottom wall 110b generally having a thickness of about 0.25 mm or less.

5 and 6, the lens apertures 110 generally have an upper diameter of about 22 mm and preferably have a depth greater than this value, preferably greater than the diameter of the contact lens 84 to be tested. Usually, the contact lens 84 has a diameter of about 20 mm. The lens carrier 22 shown in Figures 5 and 6 has three rows of receiving holes 110 in four rows, but this is only a preferred embodiment, as shown in Figs. The arrangement shown in FIGS. 1 to 4 is similarly constructed by accommodating the receiving apertures 110 in the lens carrier 22 in a 3x3, 3x8, 4x8, 3x10 or 4x10, or other configuration.

The truncated conical side wall 110a and the hemispherical bottom wall 110b delimiting the receiving openings 110, and the rectangular plate 106b are preferably made of light-permeable material, with polyvinyl chloride-based plastics being particularly preferred. The receiving apertures 110 and the rectangular plate 106 can be made in a single technological operation, for example by injection molding, which results in a relatively thin product, is cost effective and therefore, in practice, it is often acceptable to discard the lens carrier 22 after a single examination. Disposing of the used lens carrier 22 is also advantageous in that it avoids the formation of scratches and scratches in the walls of the receiving holes 110, which are generally to be reckoned with in the case of repeatedly used lens carriers 22. This is highly desirable because, as will be discussed below, scratches or scratches on the walls defining the opening 110 in the quality control system 10 are identified as a defect of the contact lens 84 in the opening 110, i.e., disposable lens carriers 22

With its -16, the efficiency of the arrangement of the present invention for controlling vision-enhancing lenses can be improved.

The receiving apertures 110 in the lens carriers 22 are filled during use by a liquid solution 112 such as saline. Each of the receiving apertures 110 5 in the lens carriers 22 is filled with liquid solution 112 to completely cover the contact lens 84 inserted therein. Once the contact lens 84 is positioned in the receiving port 110, the wall 84 is oriented towards the lowest position by the design of the wall, and the center point 10 of the contact lens 84 can be provided without further action by properly configuring and adjusting the parameters of the receiving port 110.

Returning to Figure 4, the support 24 will now be described in more detail. The function of this is to hold and firmly hold the lens carrier 22 as it is moved along with the contact lenses 84 therein to the appropriate positions of the quality control system 10, thereby allowing individual inspection of the contact lenses 84. Preferably, the support 24 moves the lens carrier 22 continuously along a well-defined path, thereby transferring contact lenses 84 successively to the illuminating light beam. One embodiment of the support 24 is that, as the lens carrier 22 is moved, a plurality of receiving apertures 110 enter a ha20 radius of each of the illuminating components 14 of the quality control system 10. After completion of the examination of contact lenses 84 in each of the rows 110, the support 24 moves the lens carrier 22 to such an extent that a subsequent row of the receiving apertures 110 is brought to the appropriate control position.

As shown in Fig. 4, a preferred embodiment of the support 24 is to hold the frame 102 with the base plate 100 on the transfer table 92 to 25 so as to move laterally, to the right or left of the drawing, while the frame 104 is designed to: it is capable of moving up or down in the frame 102 in the plane of Figure 4. The lens carrier 22 is held firmly relative to the frame 104. The first stepping motor 94 is connected to the base board 100, it can move the frame 102 transversely to the base board 100, while the second stepping motor 96 is connected to the frame 102, thereby allowing the frame 104 to be moved as needed. There is no particular restriction on the construction and structure of the frames 102 and 104, and the first stepping motor 94 and the second stepping motor 94, and may be selected according to the preferred configuration of the support 24. It will be apparent to those skilled in the art that the support 24 may be constructed in a variety of ways, not illustrated herein, since the lens carrier 22 or the like can be delivered to the quality control system 10 in a variety of ways.

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Referring now to Figure 1, the illuminator 14 and imaging assembly 16 utilize the effect of dark field illumination as the lens 80 passes through the quality control system 10. In this method, the image of the corrective lens 80 is formed on a pixel field 46 consisting of 146 pixels, wherein the light passing through the corrective lens 80 is scattered or reflected depending on the structure being examined. Dark-field illumination is a very effective method, whereby fractures and other irregularities in the structure of the lens 80, and in particular of the contact lens 84, can be effectively detected, since light is scattered in each of the failure areas. Of course, the scattering of light is observable throughout the structure of the corrective lens 80, but very small defects in areas which appear to be insignificant due to changes in scattering intensity are also detectable by dark field illumination.

The principle of dark field illumination is illustrated with reference to Figure 7. This figure illustrates an optical system for examining a vision enhancement lens 114, wherein the vision enhancer lens 114 is illuminated by a collimated light beam 116 that exits the first enhancement lens 114 to a first beamforming lens 120. Behind the first beamforming lens 120, a second beam forming lens 122 is disposed therebetween, a dark stop member 124 providing coverage, and a beam of light 126 exiting the second beamforming lens 122. In this way, pixel 206 image 126 can be used to obtain the image enhancement lens 114 examined. In the event that the fully collimated light of the collimated light beam 116 can be collected at the focal point of the first beamforming lens 120 after falling onto the vision enhancer lens 114. If the collimated light beam 116 is not affected by the vision enhancement lens 114, because of the incompletely collimated nature of the light beam, after falling onto the first beamforming lens 120, the small diameter circle 256 remains at the rear focal point of the first beamforming lens 120. The dark stop member 124 is disposed on the opposite side of the first beamforming lens 120, in the plane receiving the rear focal point, and is masked by choosing the dimensions of the stop member 124, which is slightly larger than the circle 30 based on the collimated beam 116, the first beam forming lens 120 forms at this location.

Thus, if no light scattering or refraction occurs in the collimated beam 116, i.e., the vision enhancing lens 114 is either perfect or missing from the lens carrier 22, no light appears after the translucent baffle member 124, so the pixel field 35126 remains in the dark. However, the vision-enhancing lens 114 always exhibits features that cause a portion of the collimated light beam 116 to be light beyond the plane of the dark stop member 124, despite the action of the first beamforming lens 120.

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- 18, so that's why the 126 pixel field is finally light. The vision enhancement lens 114 is arranged in a position which is an optical conjugate of the position of the pixel field 126. The consequence of this is that the light behind the plane of the stop member 124 is focused on the pixel field 126, so that in the latter, an image of possible defects in the vision correction lens 114 can be obtained. 8. Figure 3B illustrates optical elements of a dark field illumination arrangement; this arrangement is an important part of the quality control system 10. In this figure, some important elements of the illuminator 14 and the imaging assembly 16 are also shown. As can be seen, the illumination unit 14 is housed in the housing 26 and includes a light source 30 including mirrors 32 and 34, a diaphragm 130, a power supply 132, a control circuit 134, a first adjustable support 136 and a 140, and an exit window 142. The imaging assembly 16 is based on a camera 36 and includes a stop system 40 and an illumination lens system 42. The camera 36 is housed in a housing 44 within which the pixel field 46 and aperture 50 are located, while the illumination lens system 42 is housed in a tube 52 which receives the baffles 60 in addition to the first beam forming lenses 54 and 56.

The housing 26 of the illuminator assembly 14 provides a protective structure that provides a closed environment for each member of the illuminator assembly 14. The light source 30, the mirrors 32 and 34, and the diaphragm 130 are fixed within the housing 26. As shown in Figure 8, the housing 26 is comprised of a vertical leg 26a, a horizontal bracket 26b and a horizontal support 26c, where the vertical leg 26a performs a bracket function and also receives a light source 30. Mirror 32 is positioned at the vertical leg 26a and horizontal support 26c, mirror 34 is positioned at the distal end of the horizontal support 26c away from mirror 32, and diaphragm 130 is positioned within the horizontal support 26c between mirrors 32 and 34. In the housing 26, preferably on the surface of the horizontal support 26c, an opening 26d is provided which is directly above the mirror 34, and the opening 26d is covered by the exit window 142. 8. The light source 30 generates a series of flashes or light pulses, which are transmitted to the mirror 32 within the housing 26 in the form of a beam 82. In the path of the light beam, this mirror directs light pulses through the diaphragm 130 to the mirror 34, which, by rotating the propagation direction, transmits the light pulses upward, providing illumination of the ophthalmic lens 80 to be examined through the output window 142, a beam of light 82 exits the vision enhancement lens and passes to the first beamforming lens 54.

Preferably, the light source 30 is positioned on the first adjustable support 136, since it controls the direction of the light beam 82 emitted by the light source 30. Preferably, the second adjustable support 140 serves to grip the mirror 34, since it adjusts the angle of reflection of the light beam from the mirror 32. 8.

P 93 03408 i

In the illuminating assembly 14 shown in FIG. 19, the first adjustable support 136 is formed by a tilting plate which is secured to the housing 26 and is pivotally guided about two orthogonal horizontal axes. In this embodiment of the illuminating assembly 14, the second adjustable support 140 includes a deflector 140a and a displacement member 140b, wherein the mirror 34 is connected to the deflector 140a and the latter is supported on the displacement member 140b. The displacement member 140b is movable laterally, left and right as shown in FIG. 8, i.e., the lateral position of the mirror 34 is adjustable. The pivoting member 140a is rotatable about two orthogonal horizontal axes, thereby adjusting the angular position of the mirror 34.

The imaging unit 16 receives a light beam 82 passing through a vision lens 80 positioned at a monitoring position 144 and generates an image of a light beam passing through a vision lens 80 based on the light beam. The required pixel field 46 is located inside the case 44, just behind the aperture 50. Preferably, the pixel field 46 is formed from pixels 146 so that each of its imaging light sensing elements is capable of generating an electrical signal and each of the electrical current signals they generate is proportional to or representative of the light incident on each pixel 146 as a photosensitive element.

Figure 9 shows a representative detail of the pixel field 46 consisting of pixels 146, with a plurality of photosensitive elements. Figure 9 shows that these pixels 146 are located in evenly spaced grid nodes, where the number of rows and columns is known, and in the case of a preferred pixel field 46, even millions of pixels may be used. The process of the present invention is well practiced if the pixel field 46 comprises about a thousand rows and about a thousand columns. Thus, in the grid, pixels 146 form rows and columns spaced equally apart, with the exception of pixels defining the outer edge of the pixel field 46, each pixel having eight neighbors. For example, in Figure 9. Fig. 4a shows a center pixel 146a directly above the center top pixel 146b, below the center bottom pixel 146c, left pixels 146d and right pixels 146e on the left and right respectively, and top right pixels 146f and 146g top left pixels shifted from bottom right to bottom left shifted by 146h lower right pixels and 146i lower left pixels. This is how the neighborhood of a center pixel 146a is formed.

As shown in Figure 8, the stop 40 and the first and second beam forming lenses 54 and 56 are threaded along the same optical axis 46 and aperture 50, where the housing 44 is also symmetrical to the optical axis. The stop 40, like the stop 124 shown in FIG. 7, is P 93 03408

The element 20 is disposed between the first beam forming lens 54 and the second beam forming lens 56 in a manner that provides coverage, generally in the plane of the rear focal point of the first beam forming lens 54 and the pixel field 46 in the plane of the rear focus point. The baffle plates 60 are generally annular plates having a central aperture which are inserted in the interior along the longitudinal axis of the tube 52, thereby facilitating the collimation of the light beam 82 passing through the tube 52.

With this arrangement of the first beam forming lenses 54 and 56 and the stop 40, the first beam forming lens 54 focuses on a substantial portion, or optionally, of the light transmitted through the vision enhancing lens 80 being examined, . However, in the event of a defect in the lens 80, the beam 82 is deflected to some extent - the same process occurs with the standard structure of the lens 80 as well as some of its components - i.e., the beam 82 is not fully enclosed by the first beam forming region 54. so that some of the light falls beyond the plane of the stop 40 and falls behind the first beam forming lens 54 into the pixel field 46. The observation position 144 is configured such that the vision enhancement lens 80 positioned therein is in an optically conjugated position with the pixel field 46 and therefore the light leaving the impact level 40 produces an image on the pixel field 46 which transmits information about the light scattering area of ​​the vision enhancement lens 80.

This technique of dark-field illumination works extremely effectively when irregularities in the structure of the vision-enhancing lens 80, 114 are to be uncovered. 10 illustrates, by way of example, a possible image of the pixel field 46 using the contact lens 84 shown in FIGS. 2 and 3. The image is obtained by illuminating the contact lens 84 and most of the light beam is prevented by the stops 124 and 40 respectively. However, since the thickness of the material in the ring 84c, which forms the periphery of the contact lens 84, is uneven (Fig. 3A), the light beam passing through the material between the front 86 and the back 90 is deflected and behind the plane 40 illuminates elements in 150 rings on a pixel field. Other irregularities in the contact lens 84 also provide illuminated zones in the pixel field 46. Therefore, the very small depth of surface defects in the 46 pixel field can also be easily observed. If such a small cloudy spot occurs in the interior of the lens, it will appear as a light line on the pixel field 46, while if it is in the ring 84c of the contact lens 84, it will produce dark lines in the illuminated portion of the pixel field 46. Because the edges of the 84 contact lenses are sharp enough, this 93 93408

-21 is characterized by a rapidly decreasing cross-section, sufficient light is deflected in the circumference to provide the amount of light 150 provided by the ring 150 of Fig. 10, even after the contact lens 84 has an almost perfectly formed contact lens 84.

It will be apparent to those skilled in the art that neither the type of light source 30 nor the type of camera system 36 is critical in the design of the illuminator 14 and imaging assembly 16. The same can be said for beamforming lenses. Thus, it is the duty of the skilled person to realize these components in accordance with the intended purpose. 8. In one embodiment, the light source 30 is a small arc xenon charged flashlight manufactured by Hamamatsu. This flashlight has proven to be particularly advantageous because its arc stability and lamp life is high, the intensity of the output light varies by about + 2%, and the lamp life itself is 10%.⁹ blip.

Also, in an embodiment of the apparatus shown in Figure 8, the first beamforming lens 54 in the imaging assembly 16 is selected as a 100mm focal length achromatic lens which is diffraction-free in a 2.5 ° range relative to the optical axis of the first beamforming lens 54. To support it, the tube 52 was made of aluminum, which was colored black by the anode process, and the inclusion of the baffles 60 prevented the deterioration of contrast caused by light reflected from the inner surface. The second beamforming lens 56 is a 50mm focal length lens of f = 1.8 from Nikkon. A filter of ultraviolet radiation reducing material was applied to the outlet surface of the first beamforming lens 54, which was captured by a thread at the 50 mm diameter portion receiving the first beamforming lens 54.

The stop 40 consists of a dark material, a small plastic element, 2.54 mm in diameter, secured by gluing. The stop 40 is commercially available and consists, for example, of material used for soldering masks in the manufacture of printed circuit boards, and the stop 40 itself can be made in many different sizes. The recommended size is always dependent on other parameters of the quality control system 10 and the specific size is chosen so that contrast, alignment and vibration resistance can be adjusted with maximum efficiency.

The camera 36 used in the imaging unit 16 is an exemplary high resolution rural type camera utilizing standard Nikkon lenses in the embodiment of the apparatus shown in FIG. For the 36 cameras, the first Nikkon lens with a focal length of 50 mm and a brightness of f = 1.8 (this is the second beamformer 56

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-22 lens), and the tube 52 receiving the first beamforming lens 54 is fastened to the second beamforming lens 56 by a thread. The effective field of view of a Rural Type camera is a 13.8mm square, which is about 10-15% larger than the maximum size accepted for 84 contact lenses. It is desirable that the vision enhancement lens 80 and contact lens 84 to be examined occupy a maximum portion of the field of view of the camera 36, ​​and therefore, the vision enhancer 80 is preferably automatically centered prior to inspection. In the case of the contact lens 84, the receiving apertures 110 of the lens carrier 22 are configured so as to maximize the resolution of the camera 36.

The preferred configuration of the illuminator 14 and the imaging assembly 16 shown herein exhibits a number of advantageous features. First, since the light beam 82 is multiplied during propagation, the light source 30, even as a flash lamp, may be positioned further away from the sighting lens 80, i.e., the observation position 144, resulting in a collimation of the light source 15 from the sighting lens. Second, the dimensions of the image of the arc formed by the light source 30 at the stop 40 are based on the physical dimensions of the arc: essentially the distance between the physical dimensions of the arc and the distance between the light source 30 and the first beamforming lens 54 multiplied by the quotient. 8. The target configuration shown in FIG. 5A allows minimization of the image of the discharge arc, so that the stop 40 can be small in size so that the sensitivity of the system can be improved. Third, the iris of the diaphragm 130 limits the amount of space available for the passage of light beam 82, thereby reducing the amount of light illuminated by the light beam. Preferably, the diaphragm 130 is adjusted so that the cross-sectional area 25 of the beam 82 is illuminated by a beam having a diameter of up to about 10-15% longer than the lens 80 and 84 contact lenses to be examined. diameter. By reducing the diameter of the light beam 82, the contrast between the image produced on the pixel field 46 and the areas around the image can be improved, i.e. by limiting the size of the light beam 82 to reduce the interference on the side walls 110 of the receiving lens 80. The scattered light may fall on the pixel field 46 as illumination, thereby reducing the contrast between the image being viewed and its surroundings on the 46 pixel field.

In preferred embodiments of the illuminator 14 and imaging component 16 shown herein, the magnification of the system, i.e., the ratio of the actual dimensions of the pixel field 46 to the image enhancement lens 80 is substantially equal to the typical focal lengths of the second beamforming lens 56 and first beamforming lens 54. The actual magnification of the first and second beams 54 and 56 93 03408 *

• · · ·

J ·· · •• ·· * ··· • · · · · · · · · · ·

This depends on the distance between the lens 23 and the distance between the lens 80 being examined and the first beam forming lens 54. With the help of the tilting element 140a and the shifting element 140b, the light beam reflected by the mirror 34 can be well centered and placed on the optical axis of the imaging unit 16 in good parallelism.

As described above, the imaging unit 16 is preferably formed with the first beam forming lens 54 and the second beam 56, with a defined spacing between the focal lengths of the first beam forming lens 54. The use of two beamforming lenses is expedient but not necessary. However, this is particularly advantageous because the features of the illuminator 14 and the imaging component 16 are relatively easy to handle, and there is no relationship between the rear focus plane and the image plane due to the magnification of the components.

7A, 11B for further embodiments of the optical system shown schematically in FIG. and Fig. 11C. FIGS. 6A to 9A illustrate an example illustrating a beam control configuration 152, 154, and 156, respectively. The beam guide configuration 152, 154, and 156 in the quality control system 10 is capable of directing the beam 82, leaving the image of the enhancement lens 80 from the observation position 144 to the stop 40 and pixel field 46.

11A uses a single beamforming lens 160 which receives the beam 82 directly after passing through the vision correction lens 166 and directs it to the stop 40 and the pixel field 46 respectively. In the beam control configuration 152 shown in FIG. 11A, a mirror 162 is used to direct the beam 82 to the vision enhancement lens 166, which is located in the holder 164, which is at least partially translucent. The light pulses 82 or 82 from the light source 30 pass through the mirror 162 to the vision enhancement lens 166 and from there to the beamforming lens 160. Most of the light directed at the beamforming lens 160 is captured by the stop 40, which covers the focused beam of light. However, defects in the vision correction lens 166 bend, scatter, and therefore divert a portion of the transmitted light behind the deflection plane 40 of the beamforming lens 160, appearing as a focused image on the pixel field 46 and transferring the image to the correction lens information that caused a portion of the beam 82 to reach the area behind the stop 40. A 11 A. The configuration of FIG. 3B is particularly advantageous when the screen of the camera 36 has a space-filled sensor element larger than the high-resolution screen of the above-mentioned camera named Countryside.

11B. 154, an image representing the defects of the light beam 82 to the stop 40 and the image of the defective lens 166 is shown in FIG.

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Generating -24a on 46 pixel fields means two different functions. These functions are accomplished by directing the beam 82 to the lower beamforming lens 172 via mirror 170 and then to the stop 40 and the upper beamforming lens 174 through the retaining material 164 and the vision enhancement lens 166 disposed within the retaining lens 164, respectively. located. In this arrangement, a portion of the light beam 82 directed by the mirror 170 onto the lower beamforming lens 172 passes through the stop 40 in its plane, passing through the lens 166. The light is scattered on the defects of the vision correction lens 166, passing a portion of the beam 82 along the stop 40 to the upper beamforming lens 174, which focuses the incident light on the pixel field 46 and thus provides the upper beamforming lens 176 with the image correction lens defect information. . 11B. The advantage of the arrangement shown in FIG. 6A is that the lower beam forming lens 172 and the upper beam forming lens 174 operate independently of one another.

11C. Figure 15 illustrates an optical system very similar to that described above and Figure 8. However, the beam guide configuration 156 does not include the mirror 32 and the diaphragm 130. The beam control configuration 156, on the other hand, comprises 176 mirrors, 180 first and 182 second beamforming lenses, including a stop 40 and a pixel field 46 behind them, and a vision enhancement lens 166 in the holder 164 . 11C. In the arrangement of FIG. 1B, the beam 82 is guided by the interposed mirror 176 to the vision enhancement lens 166 and then passes through the material of the holder 164 to the first beamforming lens 180. Again, a significant portion of the light incident on the first beamforming lens 180 is focused on the stop 40. However, the vision correction lens 166 may have a number of errors that cause a portion of the beam of light to appear behind the stop 40 and fall on the second beam forming lens 182 to focus the incident light on the pixel field 46. In this arrangement, the first beamforming lens 180 transmits a portion of the light from the light source 30 to the stop 40, thereby rendering it independent of the second beamforming lens 182. However, both the first beamforming lens 180 and the second beamforming lens 182 are involved in the process of obtaining an image of the defective lens 166 on the pixel field 46.

Preferably, the quality control system 10 implementing the method of the present invention is provided with a control unit capable of synchronizing the simultaneous operation of the illumination unit 14, the imaging unit 16 and the transport unit 12. This means that the control actuates the light source 30 at the required times, thereby generating a light pulse and then opening the aperture 50 if there is a vision enhancement lens 80 to be observed at the observation position 144. The main principles of the control system are schematically illustrated in FIG. 12A. FIG. 6A is a diagram showing in large lines that the transport unit 12 is always an electrical signal

P 93 03408 • · ···· * ··· • · ····· ·

-25 generates when the monitoring position 144 has a suitable receiving opening 110. The output signal of the transport unit 12 is provided, for example, by the first stepping motor 94, but any other moving unit or sensor used to drive the transfer table 92 is suitable for this purpose. A suitable solution may also be to incorporate a limit switch 5, which operates when the monitoring position 144 is set to

110 the receiving slot takes up the desired space. The output signal provided by the conveying unit 12 provides control of the aperture 50 by causing the aperture 50 to be released in its full cross-section at the required time, and the signal is fed to a delay circuit 184 which is opened after opening the aperture 50 10. when necessary, activates the control circuit 134 for operating the light source 30. 12A. In the arrangement shown in FIG. 1A, it is clear that the signal generated by the transport unit 12 is transmitted to the delay circuit 184 and to the aperture control unit 50, preferably the camera 36, ​​while the output signal of the delay circuit 184 is applied to the control circuit 134.

In an exemplary embodiment of the quality control system 10, the control and actuation times are successively shown in FIG. 12B. is shown. Such a graph or the like can be recorded after placing the vision enhancement lens 80 in the observation position 144. 24 V pulses generated by the transport unit 12 are delivered to the control circuit of the camera 36 and to the delay circuit 184 at time I (0 ms). The 50 apertures of the 36 cameras at time II (approx. 9 ms) opens when sensing the pulse fringe, and in about 9 ms the aperture 50 opens completely. The delay circuit 184, with a delay of about 15 ms, triggers the light source 30 at time III, i.e., after this time, the signal reaches the control circuit 134. In the control circuit 134, the edge of the delay pulse obtained by the delay activates a control element, which results in excitation of the light source 30 and generation of the corresponding light pulse. As mentioned above, the light source 30 is preferably a flashlight which, when the arc is ignited, becomes electrically conductive and a previously charged capacity is discharged through the lamp. The value of the capacitance and the charge voltage are determined by the total energy of the light pulse emitted by the flashlight and the duration of the pulse. Meanwhile, an appropriate interface circuit ensures that the aperture 50 remains open for an IV time, i.e., about 30 ms, and thereafter ensures that the aperture 50 is closed.

By using the aperture 50 as described above, the risk of ambient light reaching the pixel field 46 during the time interval between examinations 35 of the lens 80 is significantly reduced. In the quality control system 10, it has proven expedient that high-voltage units, electronic systems, and

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-26a is housed within a housing 26 and housed with optical components for illumination.

The intensity of light from the light source 30 should be sufficient to produce an image on the pixel field 46 that is capable of being evaluated, while not stopping the transmission of the vision enhancement lens 80 under investigation, despite its short duration. Thus, the delivery unit 12 is preferably configured such that the vision enhancement lens 80 to be examined is continuously advanced in front of the imaging unit 16. This continuous smooth motion is advantageous in that it prevents wavy or other surface disturbance on the surface of the liquid solution 112 filling the aperture 110 containing the vision enhancement lenses 80, since the fluid surface irregularities are difficult to analyze and can be eliminated.

It will be apparent to those skilled in the art that the synchronization and possible coordination of the operation of the transport unit 12, the illumination unit 14, and the imaging unit 16 may be accomplished in a variety of ways, not necessarily illustrated herein. For example, a convenient option is to operate and open the light source 30 and the aperture 50 at specified intervals, and these intervals are selected to take into account the rate at which vision enhancement lenses 80 are brought to the observation position 144.

The conveyor 12, illuminator 14 and imaging assembly 16 may conveniently be housed in a housing (not shown) to isolate these assemblies from the environment and thus not affect the illumination and imaging process in the air. This casing can be provided with a translucent front door or with a translucent window front door that allows the inside of the casing to reach and follow processes. When using such translucent surface elements, it is desirable to darken them to reduce the effect of ambient light on the illumination and imaging processes.

Figure 13 is a block diagram of the image processing assembly 20. This unit receives the output signals of the pixel field 46 in parallel and serial form in the preprocessing system 62. The electrical signals fed to the preprocessing system 62 are labeled by the quality control system 10, that is, by assigning each signal to the pixels 146 generating them. One way of transmitting the signal is, for example, transmitting the signals from the pixel field 46 of the camera 36 as a timed sequence, such that the preprocessor system 62 receives a clock signal, which is generated by the camera 36, ​​i.e., the determined. Signals fed to preprocessing system 62

P 93 03408 .:. ··. í: ·· • · ν · ♦ · ♦ ·· • 4 · · 4 · • 4 * 1 4 «·· · ·

Another way of processing it is to assign identifying information to the signals, for example in the form of a header or other form, so that 146 pixels generating that signal can be selected.

The preprocessing system 62 assigns the received electrical signals to the individual pixels 146 of the pixel field 46, and accordingly₀ orders digital data and then stores the data in a data storage so that its address is clearly associated with the address of the 146 pixel generating that electrical signal. The stored values ​​are processed by the processor 64, which receives them through 186 data buses. As will be described below, for each of the 146 pixels in the 46 pixel field, an additional I, ... I_n data is recorded which records a characteristic and the preprocessing system 62 is provided with a plurality of storage elements that store this data according to pixels 146.

The data bus 186 connects the processor 64 to its preprocessing systems 62, whereupon the data stored therein from the preprocessor system 62 can be recorded and further data recorded there. As we return, the processor 64 is loaded with a program suitable for processing and analyzing data recorded in the preprocessor system 62 and, as a result, determines at least one parameter or characteristic of each of the vision enhancement lenses 80 introduced into the quality control system 10 and whether or not the given 80 vision enhancing lenses are intended for use.

The processor 64 is connected to a storage 70, which may be hard disk or other structure, for temporary or permanent retention of data. The storage 70 may include various lookup tables used by the processor 64, and may store data obtained during or during the inspection of the vision enhancement lens 80 during the storage process. The container 70 may also be used to record the number of vision enhancement lenses 80 inspected over a period of time (1 day or longer), tracking the nature, size, and number of defects in a selected set or group of vision enhancement lenses 80.

The keypad 66 transmits the operator intervention information to the processor 64. Connected to the keyboard 66 is a connector unit 74 which can visually reproduce data or messages received from the processor 64. A video monitor 72 is connected to the preprocessing system 62 to display data recorded in the storage units of the preprocessing system 62. The l₀ based on digital data, for example, the video monitor 72 can display details of an image captured on a pixel field 46. The l_v ... I_n sets of data can also be displayed on the 72 video monitors to display refined or processed versions of the real image

P 93 03408 • * · &lt;· ** ♦ s ·· ♦ · «« 4 »4 ♦ ·· · 4

4 » ··&lt;»* •44 ··· 44 4·««

-28meg. The processor 64 can also be connected to a printer 76 via a serial / parallel converter 190, which provides recording of data input from the processor 64. It will be appreciated by those skilled in the art that the image processing unit 20 may also be provided with other input and output means by which the operator or analyst may interact with the processor 64, thereby connecting to the preprocessing system 62 and the storage 70.

The components of the image processing unit 20 are generally commercially available devices well known to those skilled in the art. The processor 64 is preferably implemented with a high-speed digital computer, while the video monitor 72 is a high-resolution color-screen unit. For example, preprocessing system 62 can be assembled from Datacube's signal processing panels, while processor 64 is designed as a computer workstation Sun 3/140 for an implemented quality control system 10.

As described above, the vision enhancement lenses 80 pass successively in front of the camera 36, ​​in which case the light source 30 generates a pulse of light which produces an image focused on the pixel field 46 through the optical system. Each imaging element of the pixel field 46 generates an electrical output signal, the magnitude of which is related to the intensity of light emitted by the pixel 146. The output current signals received for each pixel 146 are converted by the image processing unit 20 to digital values ​​and the digital values ​​are stored by the storage units of the preprocessing system 62 under identifiable addresses so as to be identifiable with each pixel 146. Of the recorded information, the one already defined is l₀ processing digital data to determine if the characteristics of the vision enhancement lens 80 transmitted in the field of view of the camera 36 meet the requirements, and more specifically, the image of the enhancement lens 80 is capable of detecting a malfunction that must be identified as unacceptable to the quality control system. It is particularly important to determine whether the material of the vision enhancement lens 80 contains a rupture or other defect that precludes the intended use of the vision enhancement lens 80 and, in particular, the contact lens 84.

FIG. 14 is a flowchart of a preferred embodiment of the data processing process performed in the image processing unit 20, with reference to the inspection of the contact lens 84 shown in FIGS. An image of the contact lens 84 is formed on the pixel field 46 and examined in the process of determining decentralization, which involves examining the concentric nature of the edges of the ring 84c, which is characteristic of the contact lens 84. In the test, the outer and inner edges of the image of the ring 84c formed in the pixel field 46 are defined, i.e., the boundaries of the inner optical zones 84a and 84b are defined. so two outlines

P 93 03408

-29 to obtain the boundary of the ring 84c. Then, in a first masking process, we attempt to filter out or reduce the effects of lesions due to broken or bent light at the edge of the receiving port 110 containing contact lens 84, while at the same time attempting to highlight defects at the edge of the contact lens 84. In the method, the detected errors are then further highlighted by a fill or purge algorithm, and in a second masking method, the data relating to individual pixels near the center of the image of the ring 84c is filtered out.

After performing steps to highlight or emphasize potential errors, the purpose of data processing is to determine whether the failure actually exists. In doing so, the pixels 146 in the pixel field 46 are examined, more specifically, for information on a selected set of pixels 146, in an attempt to identify line segments or continuous shapes that may indicate the presence of a malfunction, and the continuous shapes are cubed and recorded as failures. By analyzing the size and position of the malfunctioning possibilities, it is determined whether they actually represent a malfunction and, if so, whether the nature and severity of the malfunctions warrant rejection of the 80 vision or 84 contact lenses studied.

As mentioned above, by checking the decentralization, it is determined whether the inner optical zones 84a and 84b defining the ring 84c are concentric with each other. The examination is performed on a vision enhancement lens 80 and a contact lens 84 moving in the field of vision of the camera 36. Figure 15 illustrates the process of data processing. This shows that the pixel field 46 is scanned along straight lines 202, that is, more accurately selected from the data stored in the stores of the preprocessor system 62 for pixels 146 along a given line segment, based on the recorded addresses, and determining whether the outer edges 150a and 150b of ring 150c corresponding to ring 84c are concentric.

16A. 16B and 16B. Fig. 4A illustrates a program R1 consisting of two interconnected stages for performing the control of decentralization. The first step of the program 204 can be considered as a threshold test subroutine and is intended to assign a new intensity value to each of the 146 pixels that is characteristic of the illumination T._up or T_min is equal to, depending on whether l₀ with digital data for the pixel field 46, the illumination determined at that pixel is a given T_t above or below the threshold. Accordingly, for all of these, 146 pixeP 93 03408

-30 for which l₀ the original illumination intensity represented by digital data is greater than 127 digits, with a new intensity value of 255 digits, whereas if the original illumination is 146 pixels,₀ digital data has a value of up to 127 digits, we assign a new intensity value to zero.

In step 206 of the program, the test is continued by determining the number, position, and length of the scans along the straight lines 202, determined from the data stored in the processor 64 by selecting the initial pixels 146, and the length and direction of the scan. These parameters are selected such that, with the exception of extremely poorly decentralized vision correction lenses 80 and contact lenses 84, each of the straight lines 202 crosses both the outer edges 150a and 150b of the ring 150. For this purpose, the processor 64 or the storage 70 is preferably loaded with an occasionally updated starting address book, while the directions and lengths required for scanning along the straight lines 202 are also recorded. This list can be used for each of the 80 vision correction lenses if it is of a particular type or size and the list is updated when a new type or size of 80 vision correction lenses or contact lenses 84 is required.

Thereafter, the pixel field 46 and its associated data are scanned in 210 steps. With the exception of extremely poorly decentralized vision correction lenses 80 and contact lenses 84, dark areas appear along the edges of the ring 150 along each of the straight lines 202. When the resulting image moves from the dark zone to the light zone along the straight line 202, the addresses of the pixels 146 immediately before and after the transition and the length of the line segment as the run length f₁ file. Subroutines for selecting and delimiting the two delimiters 146 along the runlength, as well as for defining the runlength, are well known in the art, and any suitable subroutine can be used to determine decentralization.

The program then compares each run length to a predetermined threshold in step 212, and, taking into account the addresses of the first and last pixels that define the run length, and the resulting length, excludes any run length that does not reach the specified threshold. a. The purpose of the exclusion is to eliminate, or at least significantly reduce, the amount of data that reflects noise or disturbance in the illumination of the 46 pixel field, that is, as a result of incident light incident on the 46 pixel field. Such disturbances, that is, the processing process is considered noise

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-31 Data to be received is generated due to backlighting, or due to phenomena that are inevitable in practice, such as deflection of light on dust particles or other impurities, resulting in illumination of some pixels not associated with the image being examined. Experience shows that, in the vast majority of cases, these illuminated ranges to be eliminated represent a pixel or possibly a few pixels. When scanning along the straight lines 202 in step 210, such an illuminated area is found, and the processor 64 records the addresses of the first and last pixels 146, and then determines the runtime for the illuminated area. However, if the illuminated area or its associated data cannot be traced back to the presence of the ring 150 or the outer periphery 150a or inner edge 150b bordering it, then the data deemed unnecessary in step 212 is excluded from further processing.

The next step in verifying decentralization is to determine whether the addresses of pixels 146 to be considered in further processing belong to the outer edges 150a or 150b of the ring 150. This operation can be performed with any suitable subroutine. A convenient way is to compare the addresses of the first and last pixels 146 of the runlengths with one another assuming that it is located at the inner edge 150b of the ring 150 and 146 pixels away from the center of the pixel field. assume that it belongs to the outer edge 150a of the ring 150. Alternatively, the results of scanning along straight lines 202 may be divided into two groups, the first group having the first and last pixels 146, respectively, which determine the run length to the outer edges 150a and 150b of the ring 150 respectively. can be assigned, while in the second group those with the opposite of the previous one, that is, the first to determine the run length, and the last pixels 146 may be mapped to the inner edges 150b and 150a of the ring 150, respectively, as a result of the scan.

Having determined, for each of the pixels 146 examined, that it lies on the outer edge 150a or the inner edge 150b of the ring 150, the number of 146 pixels belonging to the outer edge 150a and the inner edge 150b is determined in step 216. If, on this basis, fewer than 146 pixels can be selected, then, at 220, the 80 vision and 84 contact lenses studied are classified as unacceptably decentralized and discarded. However, if at least three pixels 146 are found on both the outer edge 150a and the inner edge 150b, in step 222 (Fig. 16B), a subroutine is first created to fit a circle of pixels 146 defining the outer edge 150a of the ring 150 There is a second pixel 146 on the inner edge of 150b

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-32 - trying to roll a circle. Starting from the circles drawn in this way, the program calculates the position and radius of the center of the circles. Numerical subroutines for this purpose are well known, since the basic geometric problem is to fit a circle to three or more points, or to find a circle close to three points, and then to know the center of the circle and calculate its radius, so step 222 feasible, which can perform this matching and calculation.

After selecting the center of the two matched circles, in step 224, the distance d between the two centers is determined. This distance d is compared to the first limit d in step 226 and gives distance d₁ above 230, the lens is discarded as a poorly centered lens. If d gives distance less than limit, in step 232 it d₂ a limit equal to the maximum acceptable distance between the centers defining the outer edges 150a and 150b of the ring 150. If you give distance you give₂ greater than the limit, in step 234, relying on the designated circles, the lens is accepted as too decentralized and discarded. If, on the other hand, it turns out that ad gives distance₂ equal to or less than the limit, the decentralization check is completed for the vision enhancement lens 80 and contact lens 84 and, in step 236, the lens is considered acceptable in this regard.

If the 80 vision correction lenses have passed the decentralization control test, then the 64 processor will produce an R₂ running a program that can be used as a subroutine for defining outer edge 150a and inner edge 150b. With this subroutine, the illumination values ​​are first converted to identify pixels 146 located on the outer edges 150a and 150b of the ring 150. In general, the regular contour is not followed by either the outer edge 150a or the inner edge 150b, and the actual shape differs from the circle taken from the pixel values ​​used in the decentralization control. The new values ​​of illumination are obtained by performing several operations or changing the initial values ​​associated with each of the pixels 146 in the pixel field 46. The essence of the changes is shown in Figures 17C, 17D, 17E, 17F, 17G, 17H. 171 and 171. Figure 18 shows the determination process itself as shown in the program of Figure 18. 17A. 10A and 15B, a ring 150 is shown on a pixel field 46, which is again bordered by the outer edges 150a and 150b. 17B. Fig. 4A is a zoomed view of a highlighted portion of the ring 150 with a scan line 240 shown therein. 17B. FIG. 17C is a graph showing the intensity values ​​for pixels 146 belonging to the areas marked with darkness which can be detected along the scan line 240; FIG. is shown while lighter

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9 ·· •44 · 4444

44444

4444

In -33 zones, I, intensity values ​​are higher, for which higher values, such as digital values, can be assigned.

Execution of the program shown in FIG. 18 starts with step 242, wherein FIG. 17D and 17D. Figure 12-1, we try to find the edges. In this step, a new l is added for every 146 pixels₂ is calculated as the average of the characteristic values ​​of the given pixel and the eight pixels in its immediate vicinity (Figure 9). The l₅ intensity value and l₂ the difference between the new value for the 146 pixels in the 46-pixel field is that, with the latter average value, it gradually changes between the 146 pixels, i.e. the smallest l for the 146 pixels in the dark zone₂ value is perceptible and it gradually increases to 146 pixels fully illuminated in 46 pixel fields₂ up. The difference is shown in FIG. 17D and 17D. This can be understood by comparing FIG.

The program then proceeds to step 244₃ calculates a value for each pixel, such that every pixel has l₃ we determine the value of the new pixel for 146 pixels of a group of 146 pixels and its eight immediate neighbors₂ equal to the minimum. 17D. and 17E. FIG₃ values ​​change along scan line 240 in substantially the same way as l₂ values ​​while scanning 146 pixels. The l₂ and l₃ values ​​change in the same way when scanning in a 46 pixel field, the difference being that₃ 146 pixels have a narrower band than the largest l₂ a band of 146 pixels characterized by new values.

Then, in step 246, the process of opening the edges is shown in step l₂ and l₃ based on values, another, l₄ value continues. The essence of the definition is that l₄ = l₂ -1₃. 17F. The results of this operation are shown in FIG. It can also be seen from the figure that along the line 240 of the scan 240, FIG₄ = 0 is equal to most 146 pixels. However, in the radial direction, there is a positive value in the immediate vicinity of both the outer edges 150a and the inner edges 150b, as well as pixels 146 on the edges as they are crossed. Then, in step 250 of the program, l₅ we take the value for every 146 pixels and so that for every 146 pixels, l₅ value is valid for the given 146 pixels and eight direct neighbors₂ equals the maximum of values. However, within a given distance from the outer edges 150a and 150b of the ring 150,₅ values ​​greater than l for that 146 pixel₂ value plus the highest l₅ 146 pixels have a band slightly wider than the largest l₂ a 146 pixel bar showing a value.

The next step of the program, 252, for exploring the wind is an additional l₆to determine the value for each of the 146 pixels in l₆ = l₅ - l₂ context

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-34szerint. 17H. Figure 4A shows the result of this step, that for most 146 pixels in the 46 pixel field,₆ value is zero. However, at the outer edges 150a and 150b of the ring 150, the pixels directly at the edge radially are₆ is positive. In step 254, the program l for every 146 pixels₇ assigns a value by comparing l to the given 146 pixels₄ and l₆values, then l₇ value identifies the smaller of the previous two. The result of this step is shown in Figure 171, which shows that for most pixels 146,₇ value, but at pixels 146 at the outer edges 150a and 150b of the ring 150, the l₇ positive value. so the l₇ values, the pixels 146 at the edges of the ring 150 can be highlighted and identified.

In the final step 256 of the program outlined in FIG. 18, a threshold subroutine is used to reinforce the distinction between pixels 146 at the outer edge 150a and non-pixels 146b at ring 150a. This is done by letting each of the pixels 146₈ value, based on the fact that l₇ values ​​with a predetermined threshold, such as T_t value and from this it is concluded that the illumination of the given 146 pixels is T_up maximum or T_min is the minimum. so for 146 pixels or T_up or T_MJN value. For example, if l₇ has a value greater than 32 digits for pixels 146, l₈ value is considered to be 255 digits, whereas if the given 146 pixels is l₇ value is 32 digits or less, l₈ value is set to zero.

17J. FIG₈ of the pixels having an intensity marked with a value of 50, represents a theoretically formed image on the 46 pixel fields.

As outlined above, Ι_υ l₂, l₃, l₄, l₅, l₆, l₇ and l₈ calculating values ​​and processing the associated data yields data sets stored in the storage registers of the preprocessing system 62, i. e.₀ values ​​in a first register in l_1t in a second register the l₂ values ​​are stored, and so on, in the manner assigned to the 146 pixels. Generally, it is not necessary that each of these processing values ​​is retained during the inspection of each of the 80 vision-enhancing lenses and 84 contact lenses, and that a significant amount of storage capacity can be released, e.g.₄ After calculating the values, l₃ values, then l₆After calculating the values, l₅ values ​​are deleted.

In addition, all 146 pixels in the 46 pixel field do not necessarily require the l₂, l₃, l₄, l₅, l₆, l₇ and l₈ calculation of values. For a given type of vision correction lens 80 or contact lens 84, the image of the ring 150 must always be present in a well-defined area of ​​the pixel field 46 93 03408

-35 to start with and therefore basically enough if l₂, l₃, l₄, l₅, l₆, l₇ and l₈ values ​​are determined only for the 146 pixels in this zone. However, practice shows that in many cases the simplest solution is to process the image data generated in the 46 pixel field to each of the 146 pixels and run the calculations,₂, 5 l₃, l₄, l₅, l₆, l₇ and l₈ values ​​are determined as if, in a separate step, identifying the pixels 146 that fall into this expected processing area.

After performing a sub-routine for edge opening, the quality control system 10 performs a masking program that eliminates the effect of interfering illumination on each pixel 146 caused by the edges of the receiving apertures 110 containing the vision enhancement lenses 80 and contact lenses 84. This process is illustrated by the example of a vision enhancement lens 80 or contact lens 84 illuminated by a light source 30 formed as a flash tube, which also penetrates the boundary walls of the receiving aperture 110. The edges of the receiving aperture 110 may scatter even a relatively large portion of the light, i.e., due to defects in the optical material of the receiving material, light is transmitted behind the plane of the stop 40 and transmitted to the pixel field 46 and thus shown in FIG. FIG. 2B is a contour 260 depicting the edges of the receiving port 110. This complementary image has no relation to the vision enhancement lens 80 to be examined, and accordingly, any portion of the image indicating the presence of the receiving aperture 110 is unnecessary and even undesirable when processing data for the enhancement lens 80. The masking subroutine is therefore used to filter the effect of the image from the edge of the receiving port 110 in the pixel field 46, i.e., to determine the illumination data for the pixels 146 which completely ignore the presence of the outline 260.

The masking subroutine is R₃ 20, the first step, 262, determines whether at least three 146 pixels have been selected on the outer edge 150a of the ring 150 in step 216 and 226, respectively, and whether the tested 80 the vision enhancement lens has been accepted by the quality control system 10. If the decentralization test was negative in both steps, that is, the quality of the lens 80 and the lens 84 was not acceptable, R₃ program ends with step 262.

If R₃ the end-of-program condition is not met, i.e., the degree of decentralization is acceptable, data processing continues in steps 264, whereby coordinates of the centers of the circle centered on pixels 146 defining the outer edge 150a of the ring 150 are determined. These coordinates can be recorded at the appropriate locations on the processor 64 or storage 70 after the previous determination, i.e., if necessary, the coordinates can be read from the designated storage. Coordinates defining the circle center

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After -36 is fixed, a masking subroutine is performed in 266 steps. This subroutine on the pixel field 46 mimics a circular overlap 270 having a center coinciding with the center of the aforementioned circle and having a diameter slightly larger than the diameter of the circle at the outer edge 150a of the ring 150. The masking subroutine is then applied to each of the 146 pixels_g assigns values, the size of which depends on whether the given pixel is within or outside the masked area. This is usually solved by subroutine 1 for the pixels outside the mask₉ Assigns values ​​of = 0, while for the pixels within the mask, the subroutine accepts that for that 146 pixels,₉ = l₈.

In step 266, the radius η, which is substantially larger than the radius of the circle 150a that can be fitted to the outer edge 150a of the ring, and the coordinates of said circle (¼ Υο) are given to the masking subroutine. The subroutine then selects from the 46 pixel fields all 146 pixels that are (χθ, y₀), and record their addresses. Then, in step 272, the addresses of each of the 146 pixels in the pixel field 46 are run and checked to determine whether the₂ file. If the 146 pixels are found to have its address in the file, in step 274, l₉ = l₈ is assigned a value corresponding to the given 146 pixels. However, if the address of the 146 pixel is not included in the file, then in step 276,₉ Assign a value of 0.

Many similar masking subroutines are known in the field of quality control, and therefore, there are various options available per se for performing the 266 steps.

19C. FIG. 4A shows a pixel field 46, with pixels 146 shown in FIG₉ values ​​are illuminated with intensity corresponding to the values.

Upon completion of the masking process shown in FIG. 20, processor 64 initiates another processing process, which may be referred to as a rubber band algorithm. This algorithm analyzes and processes data relating to pixels 146 on or adjacent to the outer edge 150a of the ring 150 or adjacent to it. The flowchart for performing the rubber band algorithm is schematically illustrated in Figures 21A and 21B. These are two important parts of the process. 21A. 21B and 21B. 1 to 4, the rubber band algorithm determines coordinates of the center of the circle and radius of the circle at the outer edge 150a of the vision lens 80 and contact lens 84 in the first step of processing. As mentioned above, this data can be recorded after computing during the decentralization check, in which case the required data for this algorithm need only be retrieved from the appropriate storage location.

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Next, step 282 of the rubber band algorithm follows, in which pixel 146 can be mapped to outside edge 150a by scanning the pixel field 46 from the left inward and searching for the lighted pixel 146. The first illuminated pixel 146 may not lie at the outer edge 150a of the vision enhancement lens 805, but is somewhere else and appears only as a result of external disturbances and noises. Therefore, in step 282, more scans or searches are performed to reveal more illuminated pixels 146, and then to analyze the position of the pixels 146 found, to compare the positions, and to verify from multiple sides whether the selected pixel 10 is actually the lens 80 on the edges of your image.

When a first pixel 146 is found on the outer edge 150a of the image enhancement lens 80a, the rubber band algorithm proceeds to step 284. In this step of the algorithm, we start from the designated first pixel 146 and rotate the image of the edge of the lens 80 as much as possible, returning to the first pixel 146 found if necessary. During the first search, the algorithm f₃ in the file, the address of pixels 146 or at least a significant portion of these pixels 146 at the outer edge 150a are recorded in the image of the lens 80. The algorithm is able to determine the presence, length and size of auxiliary elements at the edge of the lens. The next step of the algorithm, 286 20, is that f₄ the file captures the addresses of each of the 146 pixels that lie at the endpoints of selected straight lines - which we will return to below. The straight lines thus defined are drawn through the larger openings in the shape of the edge of the lens 80, or through any side of the accessory members, or through these accessory members.

After performing the first traversal or search described above in the image of the vision enhancement lens 80, the rubber band algorithm determines in step 290 whether there is such a large gap in the wind that the vision enhancement lens 80 is qualitatively unacceptable. If such a gap is found, the vision enhancement lens 80 is qualified as a debris and, in step 292, a message is generated that is printed by the printer 76 30 and indicates by its content that the edge of the enhancement lens 80 is defective.

Thus, step 290 serves to control the size of the gaps, and with the success of this vision-correcting lens 80, the rubber band algorithm passes through the image portion of the image-edge portion of the vision-correction lens 80 for the second time. This further search or processing is illustrated in Figure 21B. 294, the algorithm follows surface, shallow phenomena, i.e., smaller gaps, smaller auxiliary elements, which extend outwardly from the outer edge of the lens 80, or

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They develop inward radially. In this case, the algorithm performs a test on each of the detected phenomena to determine the extent to which the quality of the 80 lens is impaired. At a given level, the 80 vision enhancement lenses are already considered defective. The evaluation may be performed by calculation, such that at least a portion of the pre-selected pixels 146 associated with the outer edge of the lens 80 are provided with two Vs; radial vector and V₂ vector called wind vectors * V₂ is formed, whereby the vector series refers to the pixels 146 included in the outer edge 150a. The radial vector passing through pixels 146 starts at the center of a circle overlaid on the outer edge 150a of the ring 150 and points to that pixel. The wind vector, on the other hand, is defined as a vector drawn between a given pixel 146 and another pixel at the outer edge 150a of the ring 150, which is forward or backward (clockwise or counterclockwise) from the selected pixel 146 at the outer edge 150a of the ring. in a direction with a specific number of 146 pixels.

At 146 pixels in any of the regular circular edges of the vision correction lens 80 and the contact lens 84, if the lens is flawless, that is, there is no slit or accessory element, the product of the two vectors defined above is substantially zero, since the vector extending radially the wind vector extends approximately perpendicular to one another. However, if there is a slit or auxiliary element at the edge of the lens 80, for each or most of the pixels 146, the product of the wind vector and the radial vector is significantly different from zero because the two vectors are in a different orientation. If the vector series exceeds a given value, the 80 vision correction lenses must be considered unfit for normal use.

If the second validation process based on traversing the edge of the lens 80 (processing relevant data) has also been successfully completed, the rubber band algorithm performs a third analysis of the pixel data corresponding to the edge of the lens 80, a new aspect of FIG. 296. This third step no longer requires tests to determine the acceptability of the 80 vision lenses, but is instead used to perform the data processing required for subsequent tests. During the third passage, a series of data no longer containing data indicating a failure directly within the outer edge 150a of the ring 150 is prepared. This set of data can be extracted from the set of data related to failures and thus obtains a set containing only data indicating fissile-type errors.

During the third pass, when searching for data corresponding to the edge of the lens 80, the rubber band algorithm determines the amount of

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-39 average radial thickness of the outer edge, then l₉ assigns a value to each pixel just inside the ring 150a outer edge 150a. For example, if an average width of six pixels is assigned to the outer edge 150a of the ring 150, the rubber band algorithm would₉ Accept the condition = 0 for all pixels 146 located at least seven and at most twenty-seven pixels in a radial direction relative to the outer edge 150a of the ring 150.

22, 23, 24, 25A, 25B, 25C, 25D, 25E, 26, 27, 28, 29, 30, 31, 32 they provide a detailed description of the rubber band algorithm described above. FIG. 22 is a view illustrating S1 for determining the localization of the first pixel P (x, y) 146 on the outer edge 150a of the ring 150; shows the routine of a subroutine. In this subroutine, first in 300 steps (χθ, y₀) coordinates are selected so that they mark the center of the circle formed during the decentralization test through the outer edge 150a of the ring 150. Then, in step 302, the radius r of the circle defined above is taken₀ value. Based on the initial data so determined, a horizontal scan is performed in step 304, starting horizontally from or around the center of the left edge in the pixel field 46. During scanning, processor 64 is recorded at those addresses in the preprocessor system 62 as shown in FIG₉ values ​​that correspond to the addresses of the 146 pixels in the horizontal line segments selected in the 46 pixel field. For each of the scans, the processor 64 checks to see how large the l₉ value and first selects the 146 pixels for which l₉ value exceeds a certain threshold. It is expedient to perform more scans to identify more 146 pixels.

For the identified pixels 146, it is generally acceptable to lie on the outer edge 150a of the ring 150. However, there may be a suitable pixel 146 somewhere in the pixel field 46 and 146 pixels out to the left of the outer edge 150a, which due to background disturbances or diffused light₉ its value is sufficiently high. This is caused by the light used during the inspection of the vision enhancement lens 80, whereby the detected pixel is identified as 146 pixels illuminated during scanning. The pixel 146 so identified should not be accepted as the pixel 146 of the outer edge 150a, so in step 306, the subroutine S. identifies the addresses of the pixels 146 considered to be such an annoyance and excludes these addresses from further processing. This S₁ subroutine is executed by defining each of the pixels 146 selected during scanning and the circle invested through the revealed pixels 146 of the outer edge 150a, that is, recorded during the decentralization check (χθ, y₀) coordinates, and then the established distances are taken as the base r₀ radius - we remind you that this radius

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-40 is assumed to be equal to the radius of the characteristic circle through the outer edge 150a. If the distance between the selected 146 pixels and the center of the drawn circle is a given d₃exceeds r₀ value, the detected pixel 146 is considered not to be around the outer edge 150a of the ring 150 and therefore the address of the pixel 146 is omitted for further processing. Similarly, the address of each pixel 146 discovered during the scan is checked to determine whether these pixels lie near the outer edge 150a, and if not, the pixels 146 farther from the outer edge 150a are excluded from further processing. Next, in step 310, the address P (x, y) of any element already identified and identified as pixels 146 on the outer edge 150a of the ring 150 is accepted.

Figure 23 shows details of the first crawl, R₄ in the form of a subroutine to solve this task. Starting at pixel 146 with a P (x, y) coordinate selected in step 312, the algorithm advances clockwise or counter-clockwise along the outer edge 150a of the ring 150, searching for outer slots 150a or greater, represented by steps 314 and 320. . Travel along the outer edge 150a can be provided by any suitable subroutine. For each pixel at the edge 146, starting from pixel P (x, y), the processor 64 verifies that the five closest columns in the row below or above the selected pixel or in the column to the right or left of the selected pixel which pixel belongs to the outer edge 150a. Whether rows or columns are scanned depends on which quarter of the 46 pixel fields the selected 146 pixels lie in. After selecting the next 146 pixels for the outer edge 150a, the processor 64 is R₄executes the subroutine as many times as necessary, examining the data for the outer edge 150a and revealing the pixels 146 for the outer edge 150a.

For each of the additional pixels 146 assumed to be at the outer edge 150a, the processor 64 optionally checks the circled image (χθ, y) of the detected pixel 146 and the outer edge of the corrective lens 80 and contact lens 84, respectively.₀) coordinate center. Based on this, processor 64 can determine that a large gap has been found if the number of consecutive pixels assumed to be at the outer edge of the lens 80 is less than a given distance d._g reduced by r₀ distance, ie r₀ - r&gt; d_g.

The processor 64 may also find that a large accessory element is present if, for a greater number of 146 pixels assumed to belong to the outer edge of the lens 80, find that r and r₀ distance difference for a given d_intact greater than distance, ie r - r₀ &gt; d_intact.

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<img file="HUT65808A_D0002.tif" />

-41 If R₄ subroutine executed a larger niche or auxiliary element, the program steps 316 and 322₂ and / or S₃ executes a subroutine to which we will return in the future. If, on the other hand, the data do not suggest the presence of a gap or auxiliary elements, R₄ subroutine continues with 324 steps.

In step 324, R₄ The subroutine checks whether the outer edge 150a of the ring 150 is completed, which may be accomplished by any suitable method or subroutine. For example, as noted above, when tracking data from an image of the edge of a vision enhancer 80, f₃ a file containing the addresses of pixels 146 belonging to the edge of the lens 80 is improved. Thus, in step 324, for example, this f₃ checking the contents of the file to determine if the 146 pixels being scanned are not among the previously scanned 146 pixels. If the f₃ If the address contains the address of the 146 pixels being examined, the processor 64 considers the scan of the image of the edge of the lens 80 to be complete, whereas otherwise the processor continues to search for pixels 146 that may be regarded as the edge of the lens 80. After completing the first search, the rubber band algorithm is R₅ subroutine, while if the first crawl has not been completed, the algorithm moves to 326 steps when the address of the 146₃ fiié content. Then, at step 330, it selects the next pixel at the edge of the lens 80 and identifies the localization P (x, y) by the address of that pixel, and then R₄ subroutine returns to step 312.

Referring to Figure 23, S₂ 24 is a flowchart of FIG. This subroutine is executed whenever there is a gap in the outer edge 150a of the ring 150 as programmed. The S₂ The first 332 steps of a subroutine are to f₄ identifies and captures in a file the addresses of the pixels 146 that define the beginning and end of the gap, and the distance between the two pixels. The formation and structure of the slits are illustrated in Figures 25A, 25B, 25C, 25D, 25E. FIG₁ and P₂and P₃ and P₄ between pixels there are 334 slots and 350 additional elements. If the program finds the slot 334, that is, for a given number of pixels 146 on the edge of the lens 80,₀ distance difference d_g less than a distance, the last 146 pixels on the edge of the lens 80 prior to a series of 146 pixels may be regarded as the P₁ or P₂ pixels.

After searching for the slit, the end thereof can be determined by analyzing data for pixel 146 for slit 334 by traversing pixels 146 on a peripheral edge aligned with the outer edge of the corrective lens 80 and defined inward and outward with respect to the outline we keep track of distance until illuminated pixel adaP 93 03408

-42t is not found, more precisely sub₉ 146 pixels are not found. After selecting the edge of the lens 80, the slit is identified as a series of consecutive pixels 146 at least a certain distance from the theoretically selected circle. For each pixel in this series, r₀ and the difference r is less than d_g. The last pixel prior to this series of consecutive pixels 146, and considered to be at the edge of the lens 80, is identified as the pixel defining the end of the slot 334.

As shown in Figure 24, S₂ in the subroutine, then, in step 340, P₁ and P₂ 25B between pixels. A line is drawn, to which the maximum illumination intensity is assigned, followed by S₂ subroutine returns R₄ subroutine.

Figure 26 is a view of S, already mentioned in connection with Figure 23₃ is a flowchart of the subroutine shown in R₄ step 322 is performed when an additional element 350 is identified at the outer edge 150a of the ring 150. The S₃ During the execution of a subroutine, first attempts are made to find different bridging lines for the auxiliary element 350. Thus, in step 352, the subroutine is P₃ and P₄ identifies pixels (Fig. 25B) that mark the beginning and end of the auxiliary element 350 on the outer edge 150a of the ring 150. FIG. Then, in step 354, P₃ and P₄ drawn between pixels l_₂ For each of the 146 pixels in a straight line (Fig. 25C), see Fig. 1₉ value is assigned by T_up level. The next 356 steps of the program are P₅ for detecting a pixel extending 150a from the outer edge 150a of the ring 150 prior to the start of the auxiliary element 350, either clockwise or anticlockwise, and then, at 360,₅ pixels d₄ distant D₆ pixels are selected on the outer surface of the auxiliary element 350. Like the 25D. and then, in step 362, P₅and P₆ L overlapped pixels₃ For each pixel on the line, the previous l₉ instead of T_up value.

In the process, the subroutine then performs step 364, resulting in an additional P₇ identifies the address of the pixel such that this ring 150 is located on the outer edge 150a of a given number of pixels 146 a distance from the pixel designating the end of the auxiliary element 350. Then, in step 366, the edge of the auxiliary element 350 is shown in FIG₇ given by pixels d₅ in the distance P₈ pixel. Then, in step 370, step 25E. and P₇ and P₈ pixels connecting L₄ for each pixel lying on the line, l₉value in T_up level. 25E. Figure 5 is a schematic drawing of the bridging lines shown in Figs₃ subroutine returns R₄ subroutine.

After the first tour of the image of the 80 vision enhancing lenses, R₅ subroutine. This is illustrated in Figure 27 and is intended to accomplish this step

- storing whether the width of the gap 334 revealed from the data during the first rotation of the image of the edge of the corrective lens 80 does not reach the degree at which the corrective lens 80 should be considered unfit for use. The R₅ In the first step of subroutine 376, it is determined whether 334 gaps have been found in the analysis of the data on the edge of the lens 80. If not, R₅ subroutine terminates and the rubber band algorithm R₆ continues with subroutine. However, if the first test showed the presence of 334 gaps, R₅ subroutine continues in step 380. The latter means that the width of each of the 334 slits exposed at the edge of the 80 enhancing lens is given by a predetermined d₅ and if that width gives₅ greater than 80, the vision enhancing lens 80 is judged to be unsuitable for its intended use, filtered in step 382, ​​and a corresponding error message is generated. If, on the other hand, it gives each of the slots 334₅ widths less than a distance, R₅ subroutine is completed and R in the rubber band algorithm₆Subroutine continues to perform a second traversal of the image of the vision enhancement lens 80, and more specifically, a second analysis of image data.

PRICE₆ The structure of the subroutine is shown in Figure 28. As mentioned above, this subroutine basically looks for smaller gaps and small additional elements at the edge of the lens 80, the ones previously described in the R₄ Subroutine failed to identify 334 slots or 350 additional elements. In the program depicted in Figure 28, in step 384, the P (x, y) address of the 146 pixel is selected such that₃ with the first 146 pixels in the file. Then, in steps 386 and 390, V₁ wind vector (tangential vector) and V₂ a radial vector was taken and transformed into a vector product in 392 steps. AV₁ a wind vector extends between the second pixel 146 located at the pixel 146 defined by the address P (x, y) and a specified number of pixels relative to this pixel, rearward or forward, at the edge of the lens 80, i.e. along the edge of the lens 80, while V₂ the radial vector is a vector starting from the center of the outline of the ring 150 and lying on the outline and passing through a pixel 146 defined by the address P (x, y). The angle and vector product of the two vectors can be easily calculated from the addresses of known pixels 146 which define them.

As shown in Fig. 29, if the pixel designated P (x, y) belongs to the regular contour of the lens 80,₁ the wind vector extends substantially tangentially to the edge of the lens 80, as shown in vector 394. If vector 394 is tangential, then radius V at that 146 pixel₂ its vector product with a radial vector will assume essentially zero value. However, if the pixel designated P (x, y) is in the region of irregular shape of the edge of the lens 80, such as a slot 334

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-44 or on the surface of the auxiliary element 350, the wind vectors V, defined as vectors 396 and 400 of FIG. 29, are represented by vectors pointing to the given pixel P (x, y).₂ they are not perpendicular to a radial vector, so the vector product of the two vectors takes a value significantly different from zero.

The program shown in FIG. 28 in step 402 is the wind vector and V₂ examines a vector product of a radial vector in the sense that it is a predetermined d₇ value. If the vector product reaches or exceeds this value, i.e., there is a relatively large gap 334 or 350 in the 146 pixel environment, labeled P (x, y), the vision enhancement lens 80 is considered unsuitable for normal use and discarded in step 404 with an appropriate error message. when R₆ subroutine ends. However, if you give in step 402₇ is a vector product less than the value of P (x, y), either in the range of 146 pixels or in a regular circular edge, or in a margin of deviation from the regular circle shape, R₆ subroutine continues in step 406, where it is checked whether the image of the edge of the vision enhancer 80 is completely traveled. This is basically done by examining the P (x, y) address of the pixel in f₃ in their file. If so, the second crawl is considered complete and the rubber band algorithm is R₇continues in a subroutine. However, if it appears in step 406 that the second processing of the data on the edge of the lens 80 is not completed, in step 408, the address P (x, y) of the pixel is selected to be the address f₃ file is listed as the next 146 pixels in order, then R₆ subroutine returns to step 386 (arrow F). Thereafter, steps 386, 390, 392, 402, 404, 406, and 408 are repeated as appropriate until either the quality of the lens 80 is unacceptable or the quality of₃ all the titles in the file are exhausted, with V, wind vectors and V for each 146 pixels₂ vector product of radial vectors was determined. If the vision-correcting lens 80 was satisfactory during the test, the rubber band algorithm is R₇continues in a subroutine that performs a third pass, more precisely processing, of the data obtained from pixels 146 on the edge of the image of the lens 80.

It is preferable that the aforementioned vector product is not calculated for all 146 pixels of the edge of the lens 80, and especially if this operation is not for the pixels on the edge of the slots 334 or auxiliary parts 350, i.e. 146 during the first screening. let's do it. The vector product does not need to be determined for these slots 334 and 350, since it follows from the previous data that 146 pixels belong to either slots 334 or 350 and can save significant processing time,

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-45ha for these 146 pixels, neither does V! wind vector or V₂ neither the radial vector nor the vector product of the aforementioned vectors is calculated.

PRICE₆ 30, after completion of the subroutine, the rubber band algorithm is illustrated in FIG₇ continues with the execution of a subroutine, which, as mentioned above, is the third processing of data of pixels 146 in the image formed by the edge of the lens 80. As stated above, the purpose of the third processing is to l₁₀generating a set of values ​​that do not include any data associated with fissures within the outer periphery of the lens 80. In Fig. 30, R₇subroutine is quite detailed, it can be stated that this program consists of three main parts. In the first main section, each of the pixels 146 is defined for each pixel₉ is equal to l₁₀ value. In the second main part, an average width N is calculated for the outer edge 150a of the ring 150, while in the third main part, for pixels 146 within a selected size range within the boundary with the average thickness value,₁₀ values ​​are set to zero.

Turning to the details, we can say that R₇ in a subroutine, in step 410, for every 146 pixels of l₉ based on a value equal to l₁₀ values ​​are given. Subsequently, in step 412, outer pixels 414a, 414b, 414c, 414d and 414e are selected at the outer edge 150a of the ring 150, as well as at the outer periphery of the ring 150, as shown in FIG. Then, in step 416, R₇ in the subroutine, the number of illuminated 146 pixels in the beams 420a, 420b, 420c, 420d, 420e pointing to the selected outer pixels 414a, 414b, 414c, 414d and 414e is counted. PRICE₇ For example, a subroutine may, during execution, view the outermost outer pixels 414a, 414b, 414c, 414d, and 414e at outer edge 150a as first pixels, then search radially from there, and increase the calculated value one by one to find 146 pixels illuminated along the radius. Then, in step 422, the average number of illuminated pixels at rays 420a, 420b, 420c, 420d, 420e is determined, which can be done simply by averaging, i.e., the predetermined number of illuminated pixels 146 is determined by radial scanning (420a, 420b, 420c, 420d, 420e). Usually, the average value is not an integer and therefore it is advisable to take this average value as an integer value, that is to say, the following integer value.

PRICE₇ the subroutine then performs a third processing among the outer edge data 150a of the ring 150, first selecting, in step 424 (FIG. 30), an initial address P (x, y), which is located at the outer edge of the ring 150a 414a, 414b, 414c, 414d; belongs to one of the outer pixels and selects the edge region of the vision correction lens 80 and the contact lens 84, respectively. Then, in steps 426 and 430, starting inward from the inner boundary of the average thickness wind,

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-46and non-edge 146 pixels in l₁₀ values ​​are set to zero. For each outer pixel 414a, 414b, 414c, 414d and 414e of this outer edge of the ring 150, starting at R₇ subroutine counts N 146 pixels first along the radius of the 80 enhancing lenses. Moving further along the beam to the pixels that can be counted afterwards, the program is l₁₀ sets the value to zero. As shown in FIG. 32, this step generates a theoretical embodiment in which the edge of the vision enhancer lens 80 contacts a cross-hatched region 432, whereby the pixels 146 are₁₀ Value = 0.

PRICE₇ In step 434 of the subroutine (FIG. 30), the program checks whether the third analysis of image data from the edge of the lens 80 is completed. This can be done by essentially any known control subroutine. For example, it is advantageous if R₇ 146 pixels selected as a starting pixel when starting a subroutine are f₃ file and then continue processing until steps 426 and 430 are f₃ fiié's last 146 pixels have not been done. Alternatively, the addresses of the pixels 146 used in steps 426 and 430 are recorded separately in the R₇ subroutine, and when you want to add a new 146 pixel address to the address list, we check the list to see if the address you want to add is included. If the address under investigation is already on the list, the third processing of the data for the edge of the vision correction lens 80 and the contact lens 84 may be considered complete.

If it turns out in step 434 that this third step of processing the edges of the vision lens 80 and the contact lens 84 has not yet been completed, the address P (x, y) of the pixel examined 146 is changed to the outer 150a of the ring 150. along its edge is identified by the P (x, y) address of the nearest pixel clockwise to the 146 pixels being examined. This address can be found in f₃ then, in step 436, the P (x, y) address of the 146 pixel is aligned with the address read from the file closest to the current address. Subsequently, R₇ subroutine, as shown by arrow G, returns to step 426, after which it repeats steps 426, 430, and 434 based on the P (x, y) address of the new 146 pixel.

After the third processing of the data for the edges of the vision correction lens 80 and the contact lens 84, the processor 64₇ subroutine is considered complete and also marks the end of the rubber band algorithm.

Following the completion of the rubber band algorithm, a number of additional operations are required, the general purpose of which is to highlight any irregularity in the material of the examined and checked vision correction lens 80 or contact lenses 84 and thereby render it more manageable for control purposes.

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-47An option of additional processing methods is the already mentioned fill algorithm, based on the current signals obtained from 146 pixels in the 46 pixel field Ι_υpreparing a set of data which, in addition to the data sets so far, are capable of identifying pixels 146 associated with irregularities along the outer edge 150a of the ring 150 or on the outer edge 150a. Here is the 33. Referring to FIG. 4A, the algorithm may be used for (i) any slit 436 at the edge of the lens 80, (ii) any other irregularities 440 within the edge of the lens 80, and (iii) additional elements 442 along the edge of the lens 80 pixels carrying information, and (arc) the auxiliary elements 442 and adjacent elements, S₃ L2 generated in steps 362 and 370 of the subroutine₃and L₄ to identify pixels between line segments.

The fill algorithm also includes a number of other operations that are used to denote MAX, PMAX, MIN, and PMIN, and can be performed based on numeric values ​​assigned to the 146 pixels. In the operation MAX, a new value is set for a given pixel which is equal to the maximum of default values ​​for the eight direct neighbors of that pixel; in the PMAX operation, a new value is assigned to a given pixel 146 which is equal to the maximum of the default values ​​of the pixels directly adjacent to the given pixel in the left, right, down and up directions. In the operation MIN, however, a new value is set for a given pixel, which is equal to the minimum of the default values ​​for the eight direct neighbors of that pixel; in the PMIN operation, a new value is assigned to a given pixel 146 which is the minimum of the default values ​​of the pixels directly adjacent to that pixel in the left, right, down and up directions.

A 34B., 34C., 34D. and 34E. Figures 34A and 4A show tables obtained by performing the MAX, PMAX, MIN and PMIN operations shown in Figure 34A. Figure 1B. 34A. Figure 7A is a 7x7 table in which each number represents the data value of an associated 146 pixel, the location of the numbers in the table corresponding to the address of the associated 146 pixel. For example, for 146 pixels with the title (1,1), the value is 7, for pixels with the (4,1) value it is 0, or for (4,2), (4,7) and (5,2) For pixels 146 at address 34, the values ​​sought are 7, 0, and 0, respectively. Figure 34A shows the effect of the MAX operation when Figure 34A. This operation is performed on the numbers in the table of FIG. For example, FIG. In the table of Fig. 34A, address (2,6) has a value of 7, since in Fig. 34A. As shown in FIG. 4, one of the eight neighbors of the same pixel with a pixel of 146 has a value of 7. The same is true for the pixel (6.2), where 34B. The value of FIG. At least one of the neighbors assigned to this pixel in the table of FIGS. 34C. Figure 3A shows the effect of the PMAX operation, that is, the table

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-48 which is shown in FIG. The table is created using the PMAX operation. In this case, for example, addresses (6,3) and (6,4) have 7 values ​​since 34A. In the table of FIG. 6B, these addresses have pixels 146 having a value of 7 for their immediate right neighbors.

34D. and 34E. Figure 34A illustrates the effect of the MIN and PMIN operations, i.e., Figure 34A. The set of numbers resulting from the table shown in FIG. Thus, 34D. In Fig. 34A, address (4,3) has a zero value, whereas in Fig. 34A. In FIG. 6A, at least one of the eight neighbors of the 146 pixels at address (4,3) has a value of zero. 34E. For example, at address (4,2), a value of zero is found, whereas in FIG. The right neighbor of the pixel 146 at the same address is 0 in the table of FIG.

Figure 35 illustrates the fill algorithm R₈ shows a subroutine in a preferred embodiment. It is also shown in Figure 35 that the algorithm performs essentially fourteen different operations on data received for 146 pixels in a 46 pixel field. The required operations are performed simultaneously on the entire 46 pixel fields. The sequence of operations is as follows: MAX, PMAX, PMAX, MAX, MAX, PMAX, PMAX, MIN, PMIN, PMIN, MIN, MIN, PMIN, and PMIN. These operations are determined by the pixels in question l₉ values, and the set of data obtained after fourteen operations is referred to below Ι_υ is considered a set of data.

As a result of the processing operations performed, the surface of gaps 436, auxiliary elements 442, and other irregularities 440, which are formed at or near the outer edge 150a of the ring 150, are filled in by the program. Figures 33 and 36 show the same section of the ring 150 whereby the pixels₉36 is the l value for pixels illuminated 146 pixels_n shows the structure resulting from the values. Based on the difference between the two figures, the algorithm should be called a fill algorithm. The essential difference is that the gap 436, the auxiliary element 442 and the flaw 440, and the auxiliary elements 442 and their associated L₃ and L₄ lined with 146 pixels in zones delimited by line segments_n values ​​T_up level while l₉ the level of values ​​for the same pixels is zero.

The algorithm mentioned herein may also be known to those of skill in the art for other procedures which, at selected pixels_ncan be used to generate values.

PRICE₈ according to the subroutine, by performing the fill operation, the processor 64 initiates a second masking method which₉ subroutine. The purpose of this is to l₁₂ assigning illumination values ​​to each of the 146 pixels which

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-49 - free of undesirable light interference from the center of the circle 150b on the inner edge 150b of the ring 150 during a decentralization check. As we shall return to this, l₁₂ values ​​are used to identify malfunctions in the interior of the lens, i.e., to detect faults in the area bounded by the inner edge 150b of the ring 150.

The second masking method, R₉ The use of a subroutine in the inspection of the vision enhancement lenses 80 is very similar to the first masking procedure, which is otherwise shown in FIGS. 19A, 19B, 19C. and Figure 20. The fundamental difference between the two masking methods is that R₉ According to the subroutine, a circular mask of slightly smaller radius is used than the radius resulting from the circle laid on the inner edge 150b of the ring 150.

FIG₉ shows a flowchart of a second masking method characterized by a subroutine. PRICE_g in subroutine 446, in the first step, it is checked whether at least three 146 pixels have been applied to the inner edge 150b of the ring 150 in step 216 or 226 during the decentralization check, or whether the vision enhancement lens 80 or contact lens 84 has been defective. If the decentralized nature of the corrective lens 80 is determined, i.e., the quality of the corrective lens 80 has been found to be unacceptable in steps 216 or 226, R₉ subroutine and with it the second masking process is completed in 450 steps.

If R₉ Subroutine cannot be completed in step 446, step 452 is performed, in which the coordinates of the center of the outline fitting to the inner edge 150b of the ring 150 are determined. These coordinates are usually predefined and stored in one of the processor 64 storage registers, so that by referring to the control of decentralization, these coordinates can simply be recalled from the appropriate locations in the storage. After generating the coordinates of the center point, another masking subroutine is performed in step 454, the results of which are shown in Figures 38A, 38B. 38C. with reference to FIG. In step 454, a circular mask 456 is centered on the pixels in the pixel field 46, the center of which coincides with the aforementioned center of the circle following the inner edge 150b, but slightly smaller than the diameter of the circle 150b inside the ring. Then, in step 454, each pixel 146 is in the area covered by the circular mask 456₁₂ value. This is done so that for every 146 pixels outside the circular mask 456, l₁₂ value for a given pixel is preset to l₈ , while for the area covered by the 456 circular mask,₁₂ value is considered to be zero.

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-50At the execution of the program, in 452 steps, the coordinates of the previously defined center (Xj, y,) and their associated r₂ we take a radius where r₂ the radius being slightly smaller than the radius of the circle fitted to the inner edge 150b of the ring 150. In the masking subroutine, 454 images are then f₅ forming a file that contains the addresses of all 146 pixels out of the 46 pixel fields that are at most r from the center of (Xj, y,)₂are at a distance. Next, in step 460, we check for each of the 146 pixels in the pixel field 46 whether it is f₅ file. If the address of the 146 pixel is f₅ file, in step 462 the program for the given 146 pixels is the l₁₂ Assigns a value of 0. However, if the 146 pixels are f₅ is not found in the file, in 464 steps the program will use the l for that pixel₁₂ value in l₈ value.

The literature discloses a number of different masking subroutines that are suitable for the task outlined above and for R_g 454 of the subroutine (Fig. 37) can be performed in many different ways.

38C. FIG. 4A illustrates pixels 146 of a pixel field 46 for which the program is shown in FIG₁₂ values.

After completion of the second masking procedure, another R₁₀ subroutine, which also contains a series of operations. The purpose of this subroutine is to assign to the pixels 146 illumination values ​​that clearly distinguish the pixels 146 present in the image of irregularities or defects (fissures) from the pixels 146 that form the error-free region of the examined lens 80 or contact lenses 84. The purpose of said operation is to assign to the pixels 146 illumination values ​​which are free from changes in pixel field 46 caused by background noise or diffused illumination and are not altered by the outer and outer edges 150a and 150b of the ring 150 in its acceptable or regular shape. These operations are illustrated with reference to Figure 39.

PRICE₁₀ When executing a subroutine, first, in 466 steps, for every 146 pixels₁₃ value is determined by characterizing the given 146 pixels₁₀ of value is also characteristic of l₁₂ is subtracted. 40A, 40B. and 40C. Fig. 1A shows a detail of the ring 150 with pixels 146 respectively shown in Figs₁₀, l₁₂ and l₁₃values ​​of 146 pixels. As can be seen, the visual equivalent of the subtraction performed in step 466 is that FIG. 40B. FIG. FIG.

Then, in step 470, an operation called purification is performed to remove information about the illuminated pixels 146 that appear in the processed image. This is done by recording the pixels 146₁₃ values ​​for the entire 46 pixel fields are MAX, MIN,

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-51 PMIN and PMAX operations are performed in the above order and then done₁₄ we get a set of values. 40D. Fig. 4A shows an image of a ring formed in a pixel field 46 when l₁₄ we assign illumination values. 40C. and 40D. As can be seen from FIG. 4C, the purification operation is essentially intended to exclude information about isolated pixels from further processing, and thus to FIG. 40C. FIG. 1A eliminates the effect of interfering elements.

After the quality control system 10 is R₁ - R₁₀ subroutines or programs, so we analyzed the various errors as described above, R_n 41A and 41B. is shown. Referring to Fig. 42, the flow chart is also illustrated, showing the portion of the ring 150 where the pixels₁₄ value of illumination can be ordered.

41A, 41B. 42 and 42, the first part of the failure analysis step 472 and 474 (FIG. 41A) generates a list of starting and ending 146 addresses for each horizontal sequence of illuminated pixels 146 in succession when selecting the run length. The processor 64 scans each horizontal row of pixels 146 on the pixel field 46 and reveals which pixels 146 are illuminated during scanning. For each horizontal line, it captures the first and last 146 pixels of the illuminated range, more specifically the addresses₆ file. If you find a single insulated illuminated 146 pixel, that is, the given pixel has both illuminated 146 pixels on both the left and the right, then the address of the closing and beginning pixels will be determined and entered₆ file, and define the run lengths accordingly.

The processor 64 does not essentially scan the entire image formed by the pixel field 46, but instead executes the aforementioned address list, verifying in the storage of processor 64 the number of pixels recorded at 146 pixels forming the pixel field 46.₁₄values.

The f₆ After uploading the file, the R ^ program starts an incrementing subroutine in step 476, by means of which_6a, ... f_6n forms files for each continuous region or group of illuminated pixels 146, and more specifically for each of the interconnected distinct sets of pixels 146₁₄ values. There is no particular restriction on the type of incrementing subroutine that can be used for this purpose, any program suitable for denoting groups with selected properties. The separate f_6a, ... f_6n After creating files, the program checks in step 480 how closely the illuminated ranges are close together. If similar ranges 482 and 484 as shown in FIG. 42 are provided

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-52 - detects, merges them. This can be done, for example, by checking each of the pixels 146 in a given illuminated zone to see if there is one or more illuminated pixels 146 within a given distance that were originally assigned to another illuminated region or group. Groups 482 and 484 5 are closely related, and similar formations will hereinafter be referred to as a single formation.

Upon completion of step 480, in step 486, a subroutine is computed which computes the area and a theoretical center for each of the previously selected ranges of illuminated pixels 146, based on a combining box. Several different programs are known to perform such calculations, and it is unnecessary to recall them in detail here. PRICE_n All subroutines that allow the solution of the processing partition to be solved are useful.

PRICE_n The next task of the program, which you perform in 490 steps, is to determine the location of each illuminated area. In step 490, the center and radius of the two circles fitted to the outer edges 150a and 150b of the ring 150 are determined. This data is usually already available since it was verified during the decentralization check and stored as needed in the 64 processor storage. Usually, this data can be recorded from the processor 64 in a known manner. Then, in step 492 (Fig. 41B) The processor 64 determines where the center portions of the illuminated pixels 20 lie, i.e. (i) in the center region of the vision enhancement lens 80 and contact lens 84 and in the inner optical zone 84a (i.e., within the region 150b of the inner edge). ) or (ii) along the outer perimeter of the 80 vision or 84 contact lenses, that is, in the outer optical zone 84b (i.e., the zone defined by circles 25 on the outer edges 150a and 150b of the ring 150).

By using a number of subroutines at a point considered to be the center of a given domain, it is possible to determine that it is within a given first circle, or in the common area of ​​two circles considered concentric to one another, and since these subroutines are well known.

In the narrowest sense of the term, during the operation of the quality control system 10, R_n steps 490 and 492 are not always required in the program. However, it is expedient to perform these steps and collect the data resulting from their execution for analysis, as this will identify the types of irregularities and errors 35 that are expected to occur for a particular type of the 80 lens. The data collected in this way can provide useful guidance in the manufacturing process and in the selection of starting materials.

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After performing steps -53Α 490 and 492, the processor 64 determines that the illuminated range created from pixels 146 is large enough to be judged to be a fatal degradation or other error in the lens quality. Accordingly, in step 494, the dimensions of each region receiving the illuminated pixels 146 are analyzed and compared with a predetermined value. If, as a result, the illuminated area appears to be relatively small, therefore, the 80 vision and 84 contact lenses need not be classified as faulty. If, on the other hand, the range of illuminated pixels 146 is greater than a certain amount, then that illuminated range should be evaluated as a malfunction that precludes the proper use of the lens. The size underlying the comparison may be stored, for example, in storage 70.

Preferably, step 496 also counts the number of defects detected in a given lens 80 and contact lens 84 respectively. A fixed error rate may also be useful for analyzing the control process and selecting starting materials for the lens 80 and lens 84.

PRICE₁! The program then displays, in 500 steps, shapes corresponding to the illuminated pixels on the video monitor 72, where only areas that are larger in size than the aforementioned threshold are included. Then, in step 502, the processor 64 checks that the malfunctions are in fact attributable to the vision enhancement lens 80. If a malfunction is found, it generates, in step 504, a lens discard message to the video monitor 72 and the printer 76, after which the vision enhancement lens 80 and contact lens 84 must be removed from the quality control system 10. Subsequently, the quality control system 10 delivers a subsequent vision enhancement lens 80 or contact lenses 84 to the illuminator 14, whereupon the newly introduced vision enhancement lens 80 or contact lens 84 is illuminated by another pulsed light beam. The light beam obtained by illumination is focused on the pixel field 46 and the data processing procedure described above is repeated until it is finally determined whether the second lens is suitable for normal use.

From the foregoing description, it is obvious that quality control combined with data processing is suitable for the intended task, and the options outlined herein are particularly expedient. However, it will be appreciated that one of skill in the art will be able to make many other enhancements and changes of a non-inventive nature based on the guidance herein.

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