Image pickup lens unit and image pickup device

【0001】

[Technical field to which the invention belongs]

The present invention relates to an image pickup lens unit and an image pickup apparatus.

【0002】

[Conventional technology]

Conventionally, an imaging lens unit using a plurality of lenses, such as a camera lens, is configured to be fixed by aligning each other by arranging the lens on a mirror frame processed with high precision with metal or the like after polishing or molding the lens. Was supposed to be. Then, an image pickup lens unit integrated with such a mirror frame was attached to an image pickup apparatus provided with an image pickup element.

【0003】

Further, Patent Document 1 describes a combination lens in which two lenses having a flat surface on either the incident side or the outgoing side of the light of the lens substrate are bonded together for use in an objective lens of an optical pickup or an optical disk device. Is described.

【0004】

[Patent Document 1]

JP-A-2002-243912 (pages 1-10, FIGS. 1, 2, 8, 10, 12) [0005]

[Problems to be Solved by the Invention]

However, the conventional imaging lens unit and imaging device as described above have a problem that it is difficult to reduce the cost because the material cost and processing cost of the mirror frame and the lens assembly cost to the mirror frame are required in addition to the manufacturing cost of the lens. was there. In particular, in imaging devices such as security cameras and endoscopes, there is a tendency that smaller and smaller imaging lens units are required. Therefore, the manufacturing and assembling of the imaging lens unit used for such an imaging device becomes more and more time-consuming, and there is a problem that the manufacturing time and the manufacturing cost are pushed up.

【0006】

Further, in the technique described in Patent Document 1, since two lenses having a flat surface on one of the two surfaces are bonded together, there are only two surfaces having power, and high-performance optical characteristics such as an image pickup device and a zoom lens can be obtained. There is a problem that it is difficult to make a lens unit to be equipped. If high performance is to be achieved, there is a problem that an aspherical surface that is difficult to process and a special glass material are required, and the manufacturing cost is high.

【0007】

The present invention has been made in view of such a problem, and an object of the present invention is to provide an image pickup lens unit and an image pickup apparatus that can be manufactured in large quantities and at low cost even if they are small in size.

【0008】

[Means for solving problems]

In order to solve the above problems, in the invention according to claim 1, in the image pickup lens unit, a plurality of optical elements overlapped with the optical axes aligned with each other are joined to each other, and the side surface of each optical element is formed with the light. They are arranged in the same plane extending linearly along the axis. According to the present invention, by stacking and joining the optical elements to each other, the image pickup lens unit can be configured without using a mirror frame or the like for fixing the optical elements. Further, an imaging lens unit capable of being stably held and fixed by utilizing the side surfaces of optical elements arranged in the same plane extending linearly in the direction along the optical axis will be provided. ..

【0009】

In the invention according to claim 2, after the imaging lens unit is joined to each other in a state in which a plurality of optical element arrays including a plurality of optical elements arranged so as to align the optical axes are overlapped with each other so as to coincide with the optical axis. , Manufactured by cutting between the optical elements in the direction along the optical axis. According to the present invention, since the optical axes of the plurality of optical elements are aligned at once, the alignment process can be significantly shortened. Further, since the positioning and joining of the optical elements are performed in the state of a relatively large optical element array, the handling can be facilitated and the workability can be improved. Further, since the one to which the optical element array is joined is cut, a large number of small image pickup lens units can be manufactured.

【0010】

In the invention according to claim 3, in the image pickup lens unit according to claim 2, the MD is the maximum outer diameter of the image pickup lens unit in a cross section orthogonal to the optical axis, and the ED is an optical configuration composed of the plurality of optical elements. When defined as the maximum effective diameter of the ray of the system, a configuration that satisfies the following relational expression is used. 1.0 <MD / ED <4.0 According to the present invention, an upper limit is set for MD / ED to limit the size of the portion where the luminous flux is not incident, so that the number of optical elements arranged on one optical element array is increased. Can be done. Then, when cutting the bonded optical element array, it is possible to set a large number of products to be manufactured per cutting man-hour, and it is possible to reduce the material cost and the manufacturing cost. Further, when molding the optical element array into a mold, it is not necessary to use a large mold, so that high-precision molding becomes possible.

【0011】

Here, the maximum outer diameter of the image pickup lens unit in the cross section orthogonal to the optical axis means the diameter of the smallest cylinder among the virtual cylinders including the image pickup lens unit inside with the optical axis as the central axis. For example, when the image pickup lens unit is cut into a cylinder, it is the diameter of the cylinder, and when it is cut into a regular polygonal prism, it is the diameter of the circumscribing cylinder. Further, the lower limit of MD / ED is a self-evident necessary condition for the maximum effective light beam diameter to be within a predetermined outer diameter.

【0012】

In order to further increase the number of imaging lens units taken per optical element array and further improve productivity, it is desirable to set the MD / ED to a smaller value. Therefore, it is preferable that the image pickup lens unit satisfies the relationship of 1.0 <MD / ED <3.0. Furthermore, it is preferable to satisfy the relationship of 1.0 <MD / ED <2.0.

【0013】

In the invention according to claim 4, in the image pickup lens unit according to claim 2, when the total cutting length in the direction along the optical axis is defined as the distance TT, a configuration that satisfies the following relationship is used. .. TT <20mm According to the present invention, by setting the cutting length to be smaller than the upper limit value, the cutting time of the optical element array can be shortened and can be within a reasonable range, so that the productivity can be improved. Further, since the generation of heat at the time of cutting is reduced, the thermal distortion of the optical element can be reduced even if the optical element is continuously cut, so that the productivity can be improved while maintaining the high performance.

【0014】

In order to cut in a shorter time, it is desirable to set TT to a smaller value. Therefore, it is preferable that the image pickup lens unit satisfies the relationship of TT <15 mm. Furthermore, it is preferable to satisfy the relationship of TT <10 mm.

【0015】

In the invention according to claim 5, in the image pickup lens unit according to any one of claims 1 to 4, the side surface of each optical element is substantially parallel to the optical axis. According to the present invention, since the side surface can be easily formed, the production can be easily and quickly performed.

【0016】

The invention according to claim 6 uses the image pickup lens unit according to any one of claims 2 to 5, wherein the optical element array is a two-dimensional arrangement of optical elements. According to the present invention, it is possible to easily align the optical axes of more optical elements. Further, since the side surfaces of many optical elements can be formed by one cutting, the cutting efficiency can be improved. As a result, productivity can be improved, which is suitable for mass production.

【0017】

In the invention according to claim 7, in the image pickup lens unit according to any one of claims 1 to 6, at least one positive lens and at least one negative lens arranged adjacent to the positive lens. A configuration consisting of an optical element having a power of 10 or less including the above is used. According to the present invention, aberration correction can be performed by combining the powers of adjacent positive and negative lenses. Further, by setting the number of stacked optical elements having power to 10 or less, it is possible to maintain good optical performance without excessively accumulating misalignment errors. In order to further improve the optical performance, it is desirable to reduce the number of optical elements having power, and it is desirable to use 8 or less. More preferably, the number is 7 or less. Here, the positive lens and the negative lens mean a lens having a positive power and a lens having a negative power, respectively.

【0018】

In the invention according to claim 8, the imaging lens unit according to any one of claims 1 to 7 uses a configuration having an air interface of 10 or less. According to the present invention, it is possible to reduce the occurrence of ghosts and flares due to reflected light at the air interface. As a result, good image quality can be obtained even if the degree and number of antireflection coatings applied to the optical element are reduced, so that the manufacturing cost can be reduced without deteriorating the image quality. Since such an action effect becomes more remarkable as the number of air interfaces is smaller, the number of air interfaces is preferably 8 or less. Further, it is more preferable that the number of air interfaces is 6 or less.

【0019】

The invention according to claim 9 uses the image pickup lens unit according to any one of claims 1 to 8 in which a light absorbing member is provided on a surface other than the optical surface of the optical element. According to the present invention, since the reflected light is absorbed on the surface of the optical element other than the optical surface, it is possible to suppress the occurrence of ghosts and flares. As a result, the image quality can be improved.

【0020】

In the invention according to claim 10, in the image pickup lens unit according to any one of claims 1 to 9, an optical filter member having a side surface arranged in the same plane as the side surface of the optical element is provided on the optical element. Use a joined configuration. According to the present invention, since the optical filter member can be integrated with the image pickup lens unit, the function of the image pickup lens unit can be improved and the size can be reduced. Further, since the optical filter member can be joined by the same work as other optical elements, the process is simplified and the productivity is improved.

【0021】

In the invention according to claim 11, in the image pickup lens unit according to any one of claims 1 to 10, a hood member having a side surface arranged in the same plane as the side surface of the optical element is joined to the optical element. Use the configured configuration. According to the present invention, the hood member can suppress the generation of ghosts and flares caused by external light, so that the image quality can be improved. Further, since the hood member can be joined by the same work as other optical elements, the process is simplified and the productivity is improved.

【0022】

In the invention according to claim 12, the image pickup apparatus includes the image pickup lens unit according to any one of claims 1 to 11. According to the present invention, it is possible to obtain an image pickup apparatus having the same effect as that of the invention according to any one of claims 1 to 11.

【0023】

In the invention according to claim 13, in the image pickup apparatus according to claim 12, a configuration in which an image pickup element is bonded to an optical element forming the final surface of the image pickup lens unit is used. According to the present invention, the image pickup lens unit can be joined to the image pickup element without providing a complicated mounting structure. As a result, the manufacturing cost can be reduced. In addition, the positioning accuracy between the optical element and the image pickup element is improved.

【0024】

In the invention according to claim 14, the image pickup apparatus according to claim 13 uses a configuration in which the image pickup element has an end surface arranged in the same plane as the side surface of the optical element. According to the present invention, such an imaging device is obtained as follows. That is, a plurality of image pickup devices are arranged on one wafer. On the other hand, a plurality of the same optical elements are arranged on one substrate (optical element array). This optical element array is joined in a state where the optical axes of the optical elements are aligned and overlapped. Then, it is further aligned with the wafer and joined. Then, the imaging unit can be manufactured by cutting both of them on a surface extending linearly in the direction along the optical axis. In this way, since the positioning of the plurality of image pickup elements and the plurality of optical elements can be performed at the same time, the alignment process can be remarkably simplified and the productivity can be improved. Moreover, the manufacturing cost can be reduced.

【0025】

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, the image pickup lens unit and the image pickup apparatus according to the embodiment of the present invention will be described with reference to the accompanying drawings.

[First Embodiment]

First, the image pickup lens unit of the first embodiment according to the present invention will be described. FIG. 1A is a schematic perspective view for explaining the image pickup lens unit 100 according to the present embodiment. FIG. 1 (b) is a sectional view taken along line AA of FIG. 1 (a).

【0026】

The imaging lens unit 100 has three lenses 1, 2, 4 and an optical filter 4. The three lenses 1, 2, and 4 are stacked in the optical axis direction with their respective optical axes aligned. Then, an optical filter 3 (optical filter member) having a filter surface having no power as an optical element is sandwiched between the lens 2 and the lens 4. Each optical element is integrated by joining optical elements adjacent to each other in the optical axis direction.

【0027】

The lens 1 is provided with a concave lens surface 1a and a convex lens surface 1b in the central portion, and a flange portion 1d extending in a direction orthogonal to the optical axis of the lens surfaces 1a and 1b is provided on the outer peripheral portion thereof. .. The outer circumference of the flange portion 1d is formed in a substantially square shape in a plan view, and has four flange side surfaces 1c (side surfaces) substantially parallel to the optical axis. Further, a plurality of cylindrical positioning protrusions 1e having a rectangular cross section are provided on the surface of the flange portion 1d on the lens 2 side.

【0028】

The lens 2, the optical filter 3, and the lens 4 include flange portions 2d, 3d, and 4d, similarly to the lens 1. It also has four flange sides 2c, 3c and 4c (sides), respectively. The flange side surfaces 1c, 2c, 3c and 4c arranged in the same direction are arranged (contacted) in the same plane along the optical axis direction, respectively. The outer peripheral portions of the flange portions 1d, 2d, 3d, and 4d are shaped so as to form a gap in the optical axis direction in a state of being overlapped and joined.

【0029】

Further, the lens 2, the optical filter 3 and the lens 4 have convex lens surfaces 2a and 2b, filter surfaces 3a and 3b whose surfaces have been filtered, concave lens surfaces 4a and flat lenses, respectively. It has surface 4b. Therefore, the lenses 1 and 2 are positive lenses having positive power, and the lens 4 is a negative lens having negative power.

【0030】

Further, on the lens 1 side of the flange portion 2d, as many positioning grooves 2f formed from the concave grooves fitted to the positioning protrusions 1e are provided as many as the number of the positioning protrusions 1e. The positioning portion is formed by the positioning protrusion 1e and the positioning groove 2f. The positioning protrusion 1e and the positioning groove 2f are formed at positions where the optical axes of the lens 1 and the lens 2 coincide with each other so as to fit in the direction orthogonal to the optical axis without play. The tip surface of the positioning groove 2f in the optical axis direction is formed so as to abut against the flange portion 1d. As a result, the lens 1 and the lens 2 are accurately positioned in the optical axis direction with an air gap between the lens surface 1b and the lens surface 2a. This air gap is sandwiched between the lens surfaces 1b and 2a having power, and functions as an air lens having power.

【0031】

Similarly, on the lens 3 side of the flange portion 2d, the lens 2 side of the flange portion 3d, the lens 4 side, and the optical filter 3 side of the flange portion 4d, positioning protrusions 2e, positioning grooves 3f, and positioning protrusions 3e, which are positioning portions, respectively. , A positioning groove 4f is provided. Then, the respective optical axes are aligned, and the positions are positioned so that an appropriate air gap is provided between the respective optical surfaces.

【0032】

In Fig. 1, an example of the shape of the positioning part is exaggerated for easy viewing, but what size and shape can be used if the position can be regulated in the direction of the optical axis and in the direction orthogonal to the optical axis? It doesn't matter. For example, in the shape of fitting with each other, in addition to the positioning protrusion 1e and the positioning groove 2f shown in FIG. 1 (b), a V-shaped protrusion and a V-shaped groove may be used, a pin and a pin hole may be used, or a ball and a ball hole may be used. Good. Further, a protrusion having a reference surface in each positioning direction may be provided, and the reference surfaces may be pressed against each other for positioning.

【0033】

As the joining means of the lenses 1 and 2, the optical filter 3 and the lens 4, an appropriate means can be adopted. For example, means such as adhesion with an adhesive such as UV curable resin or laser welding can be adopted.

【0034】

Each optical element can be manufactured by molding glass or synthetic resin. In particular, for an optical element having power, it is preferable to use glass as a material in order to realize more stable optical characteristics and to achieve further miniaturization. This is because glass has a large refractive index, excellent surface accuracy, and excellent uniformity and temperature stability of the glass material.

【0035】

The image pickup lens unit 100 is manufactured as follows. First, the lens 1, the lens 2, the optical filter 3, and the lens 4 are manufactured as arrays 101, 102, 103, 104 (optical element arrays) arranged in a two-dimensional lattice at the same pitch. At this time, a positioning protrusion and a positioning groove are also formed. Next, the respective arrays are positioned and joined with their optical axes aligned. Then, as shown in FIG. 2, in that state, cutting is performed along the cutting line 6 by a cutting means such as a cutter 5. In this case, the flange side surfaces 1c, 2c, 3c and 4c are formed as cuts along the cutting line 6. Therefore, the flange side surfaces 1c, 2c, 3c, and 4c are arranged in the same surface (contacting the same surface). This same plane is a plane extending linearly in the direction along the optical axis. In the case of this example, this same plane is parallel to the optical axis, but it may be non-parallel to the optical axis depending on the cutting method. If necessary, after cutting, the side surfaces 1c, 2c, 3c, and 4c of the flanges may be surface-finished by wrapping or the like.

【0036】

Positioning of each of the arrays 101, 102, 103, and 104 in the direction orthogonal to the optical axis can be performed by providing at least two positioning holes 8a and penetrating the positioning pins 8b through them. Further, for example, a manufacturing jig that holds the arrays 101, 102, 103, and 104 so as to be movable in the direction orthogonal to the optical axis may be used.

【0037】

In the image pickup lens unit 100 described above, the surfaces other than the optical surface, that is, the flange portions 1d, 2d, 3d, 4d and the flange side surfaces 1c, 2c, 3c, 4c are exposed to light by means such as painting or vapor deposition. It is preferable to perform a treatment for providing an absorbent member. In particular, such a treatment may be performed by winding a thin film member having light absorption around the flange side surfaces 1c, 2c, 3c, and 4c and fixing them. In that case, for example, a shrinkable thin film member such as rubber or a heat-shrinkable tube may be covered and fixed. Further, a non-shrinkable thin film member made of paper, synthetic resin or the like may be wound around the flange side surfaces 1c, 2c, 3c, 4c with an adhesive or an adhesive to be fixed.

【0038】

Next, the operation of the image pickup lens unit 100 according to the present embodiment will be described. According to the image pickup lens unit 100 according to the present embodiment, the optical elements such as the lenses 1, 2, 4, and the optical filter 3 are positioned and joined to each other by the optical elements adjacent to each other in the optical axis direction. There is no need for a separate member such as a mirror frame member to attach and hold the lens. As a result, there is an advantage that the number of parts can be reduced, the manufacturing cost can be reduced, and the weight and size can be reduced.

【0039】

Further, according to the present embodiment, since the positioning portion in the optical axis direction is integrally provided on the flange portions 1d, 2d, 3d, and 4d forming the outer peripheral portion of the optical surface, the component stacking error is reduced and the accuracy is high. Can be provided with an air spacing. Further, since the refracting surface provided with the air interface has a larger power than the bonded lens surface having a small difference in refractive index, by increasing the air spacing, the air spacing is narrower (including the case where there is no air spacing). Higher performance can be obtained with the same number of optical elements.

【0040】

Further, in the present embodiment, since the optical elements are provided with flange portions 1d, 2d, 3d, and 4d on the outer peripheral portion of the optical surface, positioning portions can be formed on the flange portions 1d, 2d, 3d, and 4d. Further, this flange portion can be used as a joint surface. Therefore, there is no risk of damaging or soiling the optical surface, which has the advantage of improving production efficiency. Further, protrusions are formed outward on the outer peripheral portions of the flange portions 1d, 2d, 3d, and 4d. This protrusion has a shape in which a gap is formed in the optical axis direction when other optical elements are stacked. In this way, this gap can be used as a bald portion of the adhesive or a bald portion of chips at the time of cutting.

【0041】

As described above, the image pickup lens unit 100 according to the present embodiment has a flange side surface that is aligned with the flange portions 1d, 2d, 3d, and 4d of the outer peripheral portion of each optical element on a quadrangular prism surface substantially parallel to the optical axis. It has 1c, 2c, 3c, and 4c. Therefore, one surface of this flange surface can be used as a mounting surface. Further, as described above, the image pickup lens unit 100 according to the present embodiment is manufactured by stacking and joining optical element arrays and then cutting with a cutter 5. If it is manufactured in this way, the optical element arrays including a large number of optical elements can be collectively positioned and joined to fix the positional relationship. Therefore, there is an advantage that the productivity can be remarkably improved as compared with the case where the individual optical elements are positioned and individually bonded. Such an advantage is more remarkable when each optical element is small, and is suitable for mass production of a small image pickup lens unit.

【0042】

In the above description, an example in which the number of optical elements having power is three has been described, but it goes without saying that the number of optical elements may be increased to further improve the optical performance. At that time, aberration correction can be performed by providing at least one positive lens and one negative lens. Further, the number of stacked optical elements having power is preferably 10 or less. With such a configuration, it is possible to prevent the misalignment error from accumulating too much due to a processing error of the positioning portion, an assembly error of the optical element, or the like. Further, the number of stacked optical elements having power is more preferably 8 or less, and even more preferably 7 or less. The number of stacked optical elements can be comprehensively determined from the relationship between the performance required for the image pickup lens unit 100 and the manufacturing cost.

【0043】

Further, in the above description, the size of the air spacing is not particularly limited, but it is preferable to set a limit on the size of the air spacing. If the air spacing is kept at an appropriate size, the length of the positioning portion in the optical axis direction becomes short, and machining with good dimensional accuracy becomes easy. As a result, misalignment error can be prevented during assembly. Specifically, TD is the surface spacing on the optical axis (total length of the optical system) from the first surface to the final surface of the optical system formed by joining the optical elements, and ST is the air spacing on the optical axis. When the total length (sum of air spacing) and MT are defined as the maximum value of the length of air spacing on the optical axis (maximum air spacing), it is preferable that the imaging lens unit simultaneously satisfies the following equation. ST / TD <0.7 (1) MT / TD <0.5 (2) If the upper limit of each of the above equations is met, the air spacing or the overall length of the optical system will be long, and the misalignment will be large. As a result, it becomes difficult to obtain sufficient optical performance. Further, in order to further improve the assembly / processing accuracy of the optical element, it is preferable to satisfy the following equations (3) and (4) instead of the equations (1) and (2). ST / TD <0.6 (3) MT / TD <0.4 (4) In order to further improve the assembly / processing accuracy of the optical element, the following equations (5) and (6) are satisfied instead of equations (1) and (2). Is preferable. ST / TD <0.5 (5) MT / TD <0.3 (6) [0044]

Further, in the above description, the number of air interfaces of the optical element has been described as an example of eight, but the number of air interfaces may be limited. Then, the stray light that tends to be generated at the air interface can be reduced. As a result, it is possible to prevent the occurrence of ghosts and flares and improve the image quality. Further, the optical surface that needs to be subjected to the antireflection coating treatment can be eliminated or reduced, and the cost can be reduced. Therefore, it is preferable to limit the number of air interfaces to less than 10. In order to further reduce stray light, the number of air interfaces is more preferably less than 8, and even more preferably less than 6.

【0045】

Further, in the above description, the shape of the optical surface is not particularly limited, but it is preferable to limit the curved surface shape of the optical element to make the inclination gentle. This enables measurement with a contact-type shape measuring device such as Foam Tali Surf. By using the contact type shape measuring device, the shape error can be directly known. Therefore, the quality of the component can be determined without measuring the optical characteristics. Further, by feeding back the measurement result to the manufacturing process, the manufacturing process can be improved. In addition, the shape of the optical surface can be measured quickly. As a result, there is an advantage that the efficiency of manufacturing an optical surface having power according to the present embodiment can be improved. Specifically, when the tilt angle θ is defined as the angle formed by the optical axis on the optical surface of the optical element and the normal line of the optical surface, the maximum value of the tilt angle θ of each optical surface of the optical element is 60. It is preferable to make it smaller than the degree. Further, if the maximum value of the inclination angle θ is made smaller than 55 degrees, the measurement accuracy can be further improved even when the shape error is large, so that it is preferable to easily manufacture an optical surface with high accuracy. Further, it is more preferable that the maximum value of the inclination angle θ is smaller than 50 degrees.

【0046】

Next, some modifications of the present embodiment will be described. In each case, the points different from the above-described embodiments will be mainly described. Further, in the description of the modified example, the same reference numerals are given to the members common to the description of the first embodiment described above, and the description thereof will be omitted. First, the first modification will be described. FIG. 3A is a perspective explanatory view for explaining a first modification of the present embodiment. FIG. 3 (b) is a sectional view taken along line BB of FIG. 3 (b). 3 (c) and 3 (d) are conceptual views of a cross section in the optical axis direction for explaining an example of a manufacturing method of the first modification.

【0047】

As shown in FIGS. 3A and 3B, the image pickup lens unit 110 according to this modification includes lenses 11, 12, and 13. The optical axes of each of them are aligned with each other, and the flange portions 11d, 12d, and 13d extending in the direction orthogonal to the optical axis sequentially overlap and join them. Unlike the image pickup lens unit 100 of FIG. 1, the flange portions 11d, 12d, and 13d are not provided with positioning protrusions or positioning grooves. These flange portions are substantially square in a plan view, and have flange side surfaces 11c, 12c, and 13c (side surfaces) aligned on four planes substantially parallel to the optical axis, respectively. As shown in FIG. 3A, the flange side surfaces 11c, 12c, and 13c arranged in the same direction are arranged in the same plane along the optical axis direction.

【0048】

The lens 11 is a positive lens including a lens surface 11a formed of a convex surface and a lens surface 11b formed of a concave surface. The lens 12 is a positive lens having lens surfaces 12a and 12b composed of convex surfaces. The lens 13 is a negative lens composed of a concave lens surface 13a and a flat lens surface 13b.

【0049】

The flange portion 11d on the lens surface 11b side and the flange portion 12d on the lens surface 12a side are in contact with each other. However, since the radius of curvature of the lens surface 11b and the lens surface 12a are different, an air gap is formed between the lens surfaces 11b and 12a. Further, the lens surface 12b and the lens surface 13a have the same radius of curvature, and are joined to each other via a lens adhesive. At that time, the power φ of the lens surfaces 12b and 13a, which are the junction surfaces, is the power φ of the entire optical system of the image pickup lens unit 110._AWhen, 0 <| φ / φ_A| <0.5 (7) is satisfied. Here, | a | indicates the absolute value of a.

【0050】

In this modified example, unlike the case of the image pickup lens unit 100, the positioning portion in the direction orthogonal to the optical axis of each optical element is not provided. Therefore, when the imaging lens unit 110 is manufactured from the lenses 11, 12, and 13, the optical axis of each optical element is positioned by grasping each optical element with an appropriate jig for positioning in the direction orthogonal to the optical axis. This is done by moving it to a matching position. Alternatively, the flange side surfaces 11c, 12c, and 13c of each optical element may be manufactured so that the distances from the optical axis are accurately aligned, and the flange side surfaces 11c, 12c, and 13c may be aligned with an appropriate reference surface. .. Also, instead of manufacturing from a single unit, as shown in FIGS. 3 (c) and 3 (d), arrays 111, 112, 113 (optical) in which lens surfaces 11a, 11b, 12a, 12b, 13a, and 13b are arranged. An element array) may be manufactured, and each optical element array may be moved for positioning, joined, and then cut. Note that FIGS. 3 (c) and 3 (d) are conceptual diagrams of the manufacturing process when this method is applied to this modification. As the means for joining or cutting, the same means as already described in the first embodiment can be used.

【0051】

According to this modification, three optical elements are provided, and one set of them is a bonding lens in which optical surfaces are bonded. Therefore, chromatic aberration can be corrected by appropriately selecting the refractive index of each of the bonded optical elements. As a result, a high-performance image pickup lens unit with less chromatic aberration can be obtained.

【0052】

Further, since the power φ on the joint surface is configured to satisfy the equation (7), the radius of curvature of the joint surface does not have to be excessively small, so that the joint surface can be easily machined. As a result, the optical surface used for the joint surface can be manufactured at low cost. In this modification, the number of bonded lenses is one set, but the number of bonded surfaces may be increased in order to further improve chromatic aberration. In that case, φ in Eq. (7) shall be read as the maximum value of the power of those joint surfaces.

【0053】

Further, in order to further improve the workability of the joint surface, it is preferable to satisfy the following equation instead of the equation (7) so that the radius of curvature becomes large. 0 <| φ / φ_A| <0.4 (8) In order to further improve the workability of the joint surface, it is preferable to satisfy the following equation instead of the equation (7). 0 <| φ / φ_A|<0.3 (9)【0054】

Next, a second modification will be described. FIG. 4A is a cross-sectional view in the optical axis direction for explaining a second modification of the present embodiment. 4 (b) and 4 (c) are conceptual views of the cross section in the optical axis direction for explaining an example of the manufacturing method of the second modification. As shown in FIG. 4A, the image pickup lens unit 120 according to this modification includes lenses 21, 22, 24, and 13 as four optical elements, and a luminous flux is defined between the lenses 22, 24. An opening diaphragm 23 (holding member) that regulates the shape of the lens is provided. Each optical element is provided with flange side surfaces 21c, 22c, 24c, 13c (side surfaces). The flange side surfaces 21c, 22c, 24c, and 13c arranged in the same direction are arranged in the same plane along the optical axis direction, respectively.

【0055】

The lenses 21 and 22 are plano-concave and plano-convex lenses, respectively, and are joined by the lens surfaces 21b and 22a of the respective planes. The lens 22 is provided with a positioning protrusion 22e projecting in the optical axis direction on the flange portion 22d on the convex lens surface 22b side.

【0056】

The aperture diaphragm 23 is made of synthetic resin, metal, or the like whose surface is light-absorbing, and has end faces aligned on a plane in which the flange side surfaces 21c, 22c, 24c, and 13c of the optical element are aligned. The lens 24 is a biconvex positive lens, and the lens surface 24b is joined to the concave surface of the lens surface 13a. The flange portion 24d on the side of the lens surface 24a is provided with a positioning protrusion 24e protruding in the optical axis direction. The positioning protrusions 22e and 24e are opposed to each other and are joined with the opening diaphragm 23 sandwiched between them. An air gap is formed between the lens surfaces 22b and 24a.

【0057】

As shown in FIGS. 4 (b) and 4 (c), such an imaging lens unit 120 includes arrays 121, 122, 124 (optical elements) in which lens surfaces 21a, 21b, 22a, 22b, 24a, and 24b are arranged. It can be manufactured by a method in which an array) and an array 113 are overlapped and joined and then cut. At that time, the aperture diaphragm 23 is formed after cutting by sandwiching and joining the aperture diaphragm sheets 123 provided with openings matching the arrangement pitch of each optical element between the arrays 122 and 124. As the material of the aperture drawing sheet 123, synthetic resin or metal is used.

【0058】

According to this modification, a predetermined air gap can be formed between the lens surface 22b and the lens surface 24b by the opposing positioning projections 22e and 24e. Further, since the flange portion is used for joining, the shape when the optical elements are integrated can be simplified. As a result, there is an advantage that the moldability of the optical element is improved and the productivity can be improved while ensuring the molding accuracy. Further, according to this modification, the aperture diaphragm 23 can be integrated in the image pickup lens unit 120. In this case, if the aperture diaphragm sheet 123 is used for manufacturing, the alignment and joining can be performed by the same process as the optical element array, so that there is an advantage that the assembly can be performed easily and with high accuracy.

【0059】

Next, a third modification will be described. FIG. 5A is a cross-sectional view in the optical axis direction for explaining a third modification of the present embodiment. 5 (b) and 5 (c) are conceptual views of the cross section in the optical axis direction for explaining an example of the manufacturing method of the third modification. As shown in FIG. 5A, the image pickup lens unit 130 according to the second modification includes lenses 21, 22, 24, and 13 having the same configuration as the second modification, and the flange side surfaces 21c arranged in the same direction. , 22c, 24c, and 13c are arranged in the same plane along the optical axis direction, respectively.

【0060】

However, an aperture diaphragm coat 31 is formed on the lens surface 21b of the lens 21 as a light-shielding film. A light beam of a predetermined size is incident on the lens 21 by the aperture diaphragm coating 31. A flare diaphragm coat 32 is formed on the lens surface 13b of the lens 13 as a light-shielding film. The flare diaphragm coat 32 can prevent light from entering from a portion other than the effective lens diameter. That is, the flare drawing coat 32 has a flare prevention function.

【0061】

Both the aperture drawing coat 31 and the flare drawing coat 32 can be formed by painting or vapor deposition with a light absorbing material. In the case of manufacturing using an optical element array, as shown in FIGS. 5 (b) and 5 (c), an aperture diaphragm coat 31 and a flare diaphragm coat 32 are formed on the arrays 121 and 113, respectively, and then stacked. To join.

【0062】

According to this modification, since the aperture diaphragm coat 31 and the flare diaphragm coat 32 are each formed on the optical element, it is not necessary to provide the diaphragm with a separate member. Therefore, it is possible to save the trouble of aligning at the time of joining and reduce the number of parts. As a result, productivity can be improved and manufacturing cost can be reduced.

【0063】

Next, a fourth modification will be described. FIG. 6A is a cross-sectional view in the optical axis direction for explaining a fourth modification of the present embodiment. 6 (b) and 6 (c) are conceptual views of the cross section in the optical axis direction for explaining an example of the manufacturing method of the fourth modification. As shown in FIG. 6A, the image pickup lens unit 140 according to the present modification includes lenses 21, 22, 24, and 13 having the same configuration as that of the second modification. The flange side surfaces 21c, 22c, 24c, and 13c arranged in the same direction are arranged in the same plane along the optical axis direction, respectively.

【0064】

In this modification, the hood member 41 is joined to the lens 21. The hood member 41 is made of at least a synthetic resin whose surface is light-absorbent. The hood member 41 is a wall body having an inclined inner surface 41a. The inner surface 41a surrounds the effective lens diameter of the lens 21 and extends while being expanded in the optical axis direction. With such a structure, the hood member 41 has a function of regulating the external light incident on the lens 21. The outer peripheral surface 41c is aligned with the flange side surfaces 21c, 22c, 24c, and 13c. Also in this modification, a manufacturing method can be adopted in which the hood array member 141 in which the hood member 41 is formed in an array is manufactured, and the hood array member 141 is overlapped and joined together with the optical element array and then cut.

【0065】

According to this modification, since the hood member 41 is integrally joined with each optical element, it is possible to easily and inexpensively manufacture an image pickup lens unit in which external light is less likely to be incident and the image quality is improved.

【0066】

Next, a fifth modification will be described. FIG. 7A is a cross-sectional view in the optical axis direction for explaining a fifth modification of the present embodiment. 7 (b) and 7 (c) are conceptual views of the cross section in the optical axis direction for explaining an example of the manufacturing method of the fifth modification. As shown in FIG. 7A, the image pickup lens unit 145 according to the present modification includes a condenser lens 25 instead of the lens 22 of the image pickup lens unit 120 according to the second modification.

【0067】

The lens 25 includes lens surfaces 25a and 25b (optical surfaces), and is joined between the lens 21, the aperture diaphragm 23, the flange portion 25d, and the positioning projection 25e, respectively. An air gap is formed between the lens surface 25b and the lens surface 24a. The flange surface 25c (side surface) is arranged in the same plane as the flange surfaces 21c, 24c, 13c along the optical axis direction. The lens 25 is a lens designed so that the dimension between the flange portion 25d and the positioning protrusion 25e is reduced by appropriately changing the refractive index of the glass material and the shapes of the lens surfaces 25a and 25b from the lens 22. Specifically, the lens 22 can be designed, for example, by changing to a glass material having a large refractive index, or by making either the lens surface 25a or 25b an aspherical surface.

【0068】

In such an imaging lens unit 145, when the total cutting length in the direction along the optical axis is defined as the distance TT (in this modified example, the distance H in FIG. 7A, that is, on the lens surface 21a side). The length from the flange surface 21d to the flange surface 13d on the lens surface 13b side) satisfies the following relationship. TT <20mm (10) [0069]

Further, the maximum outer diameter of the image pickup lens unit 145, that is, the smallest cylinder diameter among the virtual cylinders including the image pickup lens unit 145 with the optical axis as the central axis is defined as MD, and the maximum light ray effective diameter of the image pickup lens unit 145 is defined as ED. Sometimes satisfy the following relationships: 1.0 <MD / ED <4.0 (11) In this modified example, the image pickup lens unit 145 is cut into regular quadrangular prisms, and in Fig. 7 (a), the prisms in the optical axis direction facing each other across the optical axis. The cross section including the ridge line is shown. Therefore, D in the figure₁Is the diameter of the circumscribed cylinder of a regular quadrangular prism, which is the above MD. D in the figure₂Is the maximum effective light beam diameter of the lens surface 21a, which is the above ED.

【0070】

According to this modification, since the distance TT satisfies the equation (10), the imaging lens unit 145 is cut after the arrays 121 and 125, the aperture diaphragm sheets 123, and the arrays 124 and 113 are overlapped and joined. The cutting thickness can be made reasonable so that it can be cut in a relatively short time. As a result, there is an advantage that productivity can be improved. Moreover, since the amount of heat generated by cutting is also reduced, there is an advantage that deterioration of optical performance due to generation of thermal strain can be prevented. Further, in order to improve productivity by cutting in a shorter time, it is desirable to set the distance TT to a smaller value. Therefore, it is preferable to satisfy the relationship of TT <15 mm (12). Furthermore, it is preferable to satisfy the relationship of TT <10 mm (13).

【0071】

Further, according to this modification, since MD / ED satisfies the equation (11), the size of the portion through which the luminous flux does not pass is set within a reasonable range, and a reasonable number of optical elements can be manufactured. It can be arranged on an optical array element. As a result, there is an advantage that the number of imaging lens units manufactured per cutting man-hour can be increased and the productivity can be improved. Further, in order to further increase the number of image pickup lens units taken per optical element array and further improve the productivity, it is desirable to set the MD / ED to a smaller value. Therefore, it is preferable to satisfy the relationship of 1.0 <MD / ED <3.0 (14). Furthermore, it is preferable to satisfy the relationship of 1.0 <MD / ED <2.0 (15).

【0072】

In the above description of the fifth modification, the thickness of the lens 25 is reduced to keep the distance TT within the range of the equation (10). However, if the distance TT is within the range of the equation (10), Needless to say, any optical element may be made thinner. Further, the distance TT is equal to the thickness of the joint portion in this modification, but the distance TT may be the total length actually cut. For example, in the example shown in FIG. 1, the cut portion and the joint portion are separate, and the cut portion is shorter than the joint portion. Further, in the example shown in FIG. 2, a guide groove 7 is provided on the cutting line 6 to reduce the thickness of the cut portion.

【0073】

In the first embodiment described above, the side surface of the optical element is aligned with a quadrangular prism surface having a substantially square cross section, but the present invention is not limited to such a quadrangular prism surface. Various other shapes can be adopted depending on the manufacturing reason of the image pickup lens unit and the convenience of handling such as assembly and transportation.

【0074】

For example, linear processing is easy in manufacturing. Therefore, especially when cutting out from the optical element array, the number of steps is reduced, and the production efficiency is good if this processing method is used. Further, during processing, the outer shape of the image pickup lens unit does not have to be a square cross section, and may be, for example, a quadrangular prism surface having a rhombus cross section as shown in FIG. 8 (a). In this case, unlike the case of a square cross section, when the optical surfaces 40 are arranged close to each other so that they can be cut, there is an advantage that the optical surfaces can be formed with high accuracy because the outer peripheral portions of the optical surfaces 40 do not touch each other. Figure 8 (b) shows an example of a hexagonal cross section. In this case, since the flange portion 41 is small, there is an advantage that a lightweight imaging lens unit can be obtained.

【0075】

In particular, if a cutting method using a laser or a water jet is used, a flat surface or a curved surface extending linearly along the optical axis can be easily formed. Therefore, as shown in FIG. 8 (c), a circular cross section is formed. You may cut it out with. When the image pickup lens unit aligned on such a cylindrical surface is used as a receiving reference surface for mounting, it is extremely easy to mount because there is no directionality around the optical axis.

【0076】

Further, in the above description, the side surface of the optical element has been described as an example substantially parallel to the optical axis, but the side surface may be inclined with respect to the optical axis. For example, an inclination may occur due to a processing error at the time of cutting, or an inclination may be provided to align the weight surface with a predetermined weight surface.

【0077】

Further, in the above description, each optical element has flange side surfaces 1c, 2c, 3c, 4c provided on the flange portions 1d, 2d, 3d, 4d, 11d, 12d, 13d, 21d, 22d, 24d, and 25d as side surfaces. , 11c, 12c, 13c, 21c, 22c, 24c, 25c, 152c, but the side surface of the optical element may be the edge surface of the optical element.

【0078】

Further, in the above description, as an example convenient for manufacturing, an example in which the side surfaces of the optical elements are aligned has been described. However, in order to achieve the purpose of simply configuring the image pickup lens unit in which the mirror frame member is omitted, the side surfaces of the optical elements may not be aligned. This is because each optical element can be joined by the planes in the optical axis direction of the flange portions 1d, 2d, 3d, 4d, 11d, 12d, 13d, 21d, 22d, 24d, and 25d.

【0079】

Further, in the above description, an example of a two-dimensional array as an optical element array has been illustrated and described, but it goes without saying that a one-dimensional array may be used. Further, when it is manufactured by cutting out from an optical element array, a plurality of optical elements may be cut out in the arrangement direction to form an imaging lens unit having a plurality of parallel optical axes. At that time, the plurality of optical elements in the arrangement direction may have different types of optical surfaces.

【0080】

Specific numerical examples of the optical system that can be used in the image pickup lens unit according to the first embodiment described above will be described below. In the following, in common with each embodiment, the symbol ω represents the entire diagonal angle of view, F represents the effective F number, So represents the object point distance, and IH represents the image height. Also, ST / TD, MT / TD, tilt angle θ, | φ / φ_AThe quantities expressed as |, TT, and MD / ED have the same names and definitions as those used in the above explanation. In the table of numerical data described later, r is the radius of curvature, d is the surface spacing, and n._dIs the index of refraction, ν_dRepresents the Abbe number. r_i, D_i, N_i,ν_i(I is an integer) is the radius of curvature, the interplanar spacing, the refractive index, and the Abbe number. In each optical path diagram described later, r in the table of numerical data_i, D_i, N_iCorrespondence with is shown.

【0081】

[Example 1]

FIG. 9 is an optical path diagram of the first numerical example. FIG. 10 is an aberration diagram of this embodiment. In Fig. 10 (a), the spherical aberration calculated for wavelengths 656.27 nm, 587.56 nm, 546.07 nm, 486.13 nm, and 435.84 nm is taken as the spherical aberration (unit: mm) on the horizontal axis and the aperture ratio on the vertical axis. It is the aberration diagram shown. FIG. 10B is an aberration diagram showing astigmatism (unit: mm) on the horizontal axis and angle of view (unit: °) on the vertical axis. ΔM represents the amount of deviation of the meridional image plane, and ΔS represents the amount of deviation of the sagittal image plane. FIG. 10 (c) is an aberration diagram in which distortion (unit:%) is plotted on the horizontal axis and angle of view (unit: °) is plotted on the vertical axis.

【0082】

The configuration of this embodiment includes a first lens 51 having a positive power, a second lens 52 having a positive power, a third lens 53 having a negative power, and filter members 54 and 55 in this order from the object side. An air gap is provided between the first lens 51 and the second lens 52. The optical surfaces of the second lens 52 and the third lens 53 are joined to each other. Although not shown, a diaphragm is formed on the image side surface of the first lens 51 by thin film deposition. As shown in FIG. 11A, the air spacing between the first lens 51 and the second lens 52 is such that the first lens 51 and the second lens 52 are provided with positioning protrusions 51a and 52a, respectively, in the optical axis direction. A spacer 56 (holding member) may be sandwiched between the first lens 51 and the second lens 52 as shown in FIG. 11 (b). In addition, all the air intervals of the other numerical examples described below can be formed by any of the above means.

【0083】

In this embodiment, the object point distance So = 960 mm and the hyperfocal length is set. The total diagonal angle of view is ω = 40 °, the effective F number is F2.8, and the image height is IH = 0.924mm. In addition, there are 6 air interfaces, ST / TD = 0.42, MT / TD = 0.20, inclination angle θ is 33 °, | φ / φ_A| = 0.08. The curvature of field is corrected by providing an air gap between the first lens 51 and the second lens 52.

【0084】<img file="JP2004088713A_D0001.tif" /> 【0085】

As can be seen from FIG. 10, the image pickup lens unit of this embodiment has good aberration characteristics in the visible light region.

【0086】

[Example 2]

FIG. 12 is an optical path diagram of the second numerical example. FIG. 13 is an aberration diagram of this embodiment. Since FIGS. 13 (a), (b), and (c) are drawn in the same manner as the graphs described in FIGS. 10 (a), (b), and (c), the explanation of the graph axes and the like is omitted. To do.

【0087】

The configuration of this embodiment includes a first lens 57 having positive power, a second lens 58 having positive power, a third lens 59 having negative power, and filter members 54 and 55 in order from the object side. An air gap is provided between the first lens 57 and the second lens 58. The optical surfaces of the second lens 58 and the third lens 59 are joined to each other. Although not shown, a diaphragm is formed on the side surface of the object of the first lens 57 by thin film deposition.

【0088】

In this embodiment, the object point distance So = 960 mm and the hyperfocal length is set. The total diagonal angle of view is ω = 40 °, the effective F number is F2.8, and the image height is IH = 0.924mm. In addition, there are 6 air interfaces, ST / TD = 0.14, MT / TD = 0.09, inclination angle θ is 37 °, | φ / φ_A| = 0.09. The curvature of field is corrected by providing an air gap between the first lens 57 and the second lens 58.

【0089】<img file="JP2004088713A_D0002.tif" /> 【0090】

As can be seen from FIG. 13, the image pickup lens unit of this embodiment has good aberration characteristics in the visible light region.

【0091】

[Example 3]

FIG. 14 is an optical path diagram of the third numerical example. FIG. 15 is an aberration diagram of this embodiment. Since FIGS. 15 (a), (b), and (c) are drawn in the same manner as the graphs described in FIGS. 10 (a), (b), and (c), the explanation of the graph axes and the like is omitted. To do.

【0092】

The configuration of this embodiment is, in order from the object side, a first lens 60 having negative power, a second lens 61 having positive power, a third lens 62 having positive power, a fourth lens 63 having negative power, and a filter member. It has 54 and 55. The optical surfaces of the first lens 60 and the second lens 61, and the third lens 62 and the fourth lens 63 are joined to each other. An air gap is provided between the second lens 61 and the third lens 62. Although not shown, a diaphragm is formed on the image side surface of the first lens 60 by thin film deposition.

【0093】

In this embodiment, the object distance is So = 10 mm, the total diagonal angle of view is ω = 90 °, the effective F number is F3.0, and the image height is IH = 0.924 mm. In addition, there are 6 air interfaces, ST / TD = 0.07, MT / TD = 0.04, inclination angle θ is 46 °, | φ / φ_A| = 0.07. The curvature of field is corrected by providing an air gap between the second lens 61 and the third lens 62.

【0094】<img file="JP2004088713A_D0003.tif" /> 【0095】

As can be seen from FIG. 15, the image pickup lens unit of this embodiment has good aberration characteristics in the visible light region. In particular, looking at FIG. 15 (a), it can be seen that chromatic aberration is satisfactorily corrected as compared with the first and second examples because two sets of junction lenses are used. Furthermore, as shown in FIG. 15 (b), astigmatism is also corrected very well.

【0096】

[Example 4]

FIG. 16 shows an optical path diagram of the fourth numerical example. FIG. 17 is an aberration diagram of this embodiment. Since FIGS. 17 (a), (b), and (c) are drawn in the same manner as the graphs described in FIGS. 10 (a), (b), and (c), the explanation of the graph axes and the like is omitted. To do.

【0097】

The configuration of this embodiment is, in order from the object side, a first lens 65 having negative power, a second lens 66 having positive power, a third lens 67 having positive power, a fourth lens 68 having negative power, and a filter member. It has 54 and 55. The optical surfaces of the first lens 65 and the second lens 66, and the third lens 67 and the fourth lens 68 are joined to each other. An air gap is provided between the second lens 66 and the third lens 67. Although not shown, a diaphragm is formed on the side surface of the object of the first lens 65 by thin film deposition.

【0098】

In this embodiment, the object distance is So = 10 mm, the total diagonal angle of view is ω = 90 °, the effective F number is F3.0, and the image height is IH = 0.924 mm. In addition, there are four air interfaces, ST / TD = 0.09, MT / TD = 0.04, inclination angle θ is 45 °, | φ / φ_A| = 0.04. The curvature of field is corrected by providing an air gap between the second lens 61 and the third lens 62.

【0099】<img file="JP2004088713A_D0004.tif" /> 【0100】

As can be seen from FIG. 17, the image pickup lens unit of this embodiment has good aberration characteristics in the visible light region. In particular, looking at FIG. 17 (a), it can be seen that chromatic aberration is satisfactorily corrected as compared with the first and second embodiments because two sets of junction lenses are used. Furthermore, as shown in FIG. 17 (b), astigmatism is also corrected very well.

【0101】

[Example 5]

FIG. 18 is an optical path diagram of the fifth numerical example. FIG. 19 is an aberration diagram of this embodiment. Since FIGS. 19 (a), (b), and (c) are drawn in the same manner as the graphs described in FIGS. 10 (a), (b), and (c), the explanation of the graph axes and the like is omitted. To do.

【0102】

The configuration of this embodiment is, in order from the object side, a first lens 69 having negative power, a second lens 70 having positive power, a third lens 71 having positive power, a fourth lens 72 having negative power, and a filter member. It has 54 and 55. The optical surfaces of the first lens 69 and the second lens 70, and the third lens 71 and the fourth lens 72 are joined to each other. An air gap is provided between the second lens 66 and the third lens 67. Although not shown, a diaphragm is formed on the image side surface of the first lens 69 by thin film deposition.

【0103】

In this embodiment, the object distance is So = 10 mm, the total diagonal angle of view is ω = 90 °, the effective F number is F3.0, and the image height is IH = 0.924 mm. In addition, there are 6 air interfaces, ST / TD = 0.07, MT / TD = 0.03, inclination angle θ is 41 °, | φ / φ_A| = 0.06. The curvature of field is corrected by providing an air gap between the second lens 61 and the third lens 62.

【0104】<img file="JP2004088713A_D0005.tif" /> 【0105】

As can be seen from FIG. 19, the image pickup lens unit of this embodiment has good aberration characteristics in the visible light region. In particular, looking at FIG. 19A, it can be seen that chromatic aberration is satisfactorily corrected as compared with the first and second embodiments because two sets of junction lenses are used. Furthermore, as shown in FIG. 19 (b), astigmatism is also corrected very well.

【0106】

[Example 6]

FIG. 20 is an optical path diagram of the sixth numerical example. FIG. 21 is an aberration diagram of this embodiment. Since FIGS. 21 (a), (b), and (c) are drawn in the same manner as the graphs described in FIGS. 10 (a), (b), and (c), the explanation of the graph axes and the like is omitted. To do.

【0107】

The configuration of this embodiment includes a first lens 73 having a positive power, a second lens 74 having a positive power, a third lens 75 having a negative power, and filter members 54 and 55 in this order from the object side. The optical surfaces of the second lens 74 and the third lens 75 are joined to each other. An air gap is provided between the first lens 73 and the second lens 75. Although not shown, a diaphragm is formed on the side surface of the object of the first lens 73 by thin film deposition.

【0108】

In this embodiment, a polycarbonate resin is used for the third lens 75. In this embodiment, the object point distance So = 960 mm and the hyperfocal length is set. The total diagonal angle of view is ω = 40 °, the effective F number is F2.8, and the image height is IH = 0.924mm. In addition, there are 6 air interfaces, ST / TD = 0.14, MT / TD = 0.09, inclination angle θ is 38 °, | φ / φ_A| = 0.20. The curvature of field is corrected by providing an air gap between the first lens 73 and the second lens 74.

【0109】<img file="JP2004088713A_D0006.tif" /> 【0110】

As can be seen from FIG. 21, the image pickup lens unit of this embodiment has good aberration characteristics in the visible light region even though it uses a synthetic resin lens made of polycarbonate having a relatively small refractive index. ing. As described above, in this embodiment, since an inexpensive lens can be manufactured by using a lens made of polycarbonate which is a synthetic resin, there is an advantage that a low-cost imaging lens unit can be obtained. Using synthetic resin molding also has an advantage that positioning protrusions for providing air spacing can be easily provided.

【0111】

[Example 7]

FIG. 22 shows an optical path diagram of the seventh numerical example. FIG. 23 is an aberration diagram of this embodiment. Since FIGS. 23 (a), (b), and (c) are drawn in the same manner as the graphs described in FIGS. 10 (a), (b), and (c), the explanation of the graph axes and the like is omitted. To do.

【0112】

The configuration of this embodiment is, in order from the object side, a first lens 76 having negative power, a second lens 77 having positive power, a third lens 78 having positive power, a fourth lens 79 having negative power, and a filter member. It has 54 and 55. The optical surfaces of the first lens 76 and the second lens 77, and the third lens 78 and the fourth lens 79 are joined to each other. An air gap is provided between the second lens 77 and the third lens 78. Although not shown, a diaphragm is formed on the image side surface of the first lens 76 by thin film deposition.

【0113】

In this embodiment, ZEONEX (registered trademark), which is a synthetic resin, is used for the third lens 78, and polycarbonate resin is used for the fourth lens 79. In this embodiment, the object distance is So = 10 mm, the total diagonal angle of view is ω = 90 °, the effective F number is F3.0, and the image height is IH = 0.924 mm. In addition, there are 6 air interfaces, ST / TD = 0.07, MT / TD = 0.03, inclination angle θ is 46 °, | φ / φ_A| = 0.20. The curvature of field is corrected by providing an air gap between the second lens 61 and the third lens 62.

【0114】<img file="JP2004088713A_D0007.tif" /> 【0115】

As can be seen from FIG. 23, the image pickup lens unit of this embodiment has good aberration characteristics in the visible light region even though it is configured by using two synthetic resin lenses having a relatively small refractive index. It has become a thing. In particular, looking at FIG. 23 (a), it can be seen that chromatic aberration is satisfactorily corrected as compared with the first and second embodiments because two sets of junction lenses are used. According to this embodiment, since an inexpensive synthetic resin lens is used for two out of four lenses, there is an advantage that an inexpensive imaging lens unit can be constructed.

【0116】

[Example 8]

FIG. 24 is an optical path diagram of the eighth numerical example. FIG. 25 is an aberration diagram of this embodiment. Since FIGS. 25 (a), (b), and (c) are drawn in the same manner as the graphs described in FIGS. 10 (a), (b), and (c), the explanation of the graph axes and the like is omitted. To do. However, in FIG. 25 (a), since the data variation for each wavelength is small, the results of only wavelengths of 656.27 nm, 587.56 nm, and 486.13 nm are shown.

【0117】

In this embodiment, the first lens 80 having negative power, the parallel flat plate 81, the second lens 82 having negative power, the third lens 83 having positive power, and the fourth lens having negative power are arranged in this order from the object side. It is equipped with a lens and a fifth lens 85 with positive power. The optical surfaces of the second lens 82, the third lens 83, the fourth lens 84, and the fifth lens 85 are joined to each other. Concave surface of the first lens 80 (r₂) And the side surface of the object of the parallel flat plate 81 (r)₃), An air gap is formed. Although not shown, a diaphragm is formed by vapor deposition on the image plane side surface of the parallel flat plate 81. In this embodiment, the object distance is So = , the total diagonal angle of view is ω = 103 °, the effective F number is F4.3, and the image height is IH = 0.5 mm. In addition, there are four air interfaces, ST / TD = 0.04, MT / TD = 0.03, inclination angle θ is 45 °, | φ / φ_A| = 0.23. The curvature of field is corrected by providing an air gap between the first lens 80 and the parallel flat plate 81.

【0118】<img file="JP2004088713A_D0008.tif" /> 【0119】

As can be seen from FIG. 25, the image pickup lens unit of this embodiment has good aberration characteristics in the visible light region. In this embodiment, an air lens is formed by providing an air gap between the first lens 80 having power and the parallel flat plate 81 having no power.

【0120】

[Example 9]

FIG. 26 is an optical path diagram of the ninth numerical example. FIG. 27 is an aberration diagram of this embodiment. Since FIGS. 27 (a), (b), and (c) are drawn in the same manner as the graphs described in FIGS. 10 (a), (b), and (c), the explanation of the graph axes and the like is omitted. To do. In addition, H and D shown in the figure₁, D₂Is the same amount as described in FIG.

【0121】

The configuration of this embodiment is, in order from the object side, a first lens 87 having negative power, a second lens 88 having positive power, a brightness diaphragm 89 (holding member), a third lens 90 having positive power, and positive power. The fourth lens 91, the spacer 56, and the filter members 54, 55 are provided. Then, in this order, the first lens 87 to the fourth lens 91, which need to align the optical axes, are manufactured by being joined to each other and then cut into regular quadrangular prisms. Positioning protrusions 87e and 91e are provided on the first lens 87 and the fourth lens 91, respectively, and an air gap is formed between the first lens 87 and the fourth lens 91, respectively. The brightness diaphragm 89 is a member provided with a positioning protrusion 89e, forming a predetermined air gap between optical elements, and having an aperture diaphragm portion 89a having a light-shielding property in an intermediate portion in the optical axis direction. In this embodiment, an air gap is formed between the second lens 88 and the fourth lens 91, and the aperture stop 89a is arranged in the middle. The brightness diaphragm 89 can be manufactured, for example, by synthetic resin molding or the like. The spacer 56 forms an air gap between the fourth lens 91 and the filter member 54. In this embodiment, the object point distance is set to So = 260 mm and the hyperfocal length is set. The focal length is f = 1.47mm, the total diagonal angle of view is ω = 66 °, the effective F number is F2.8, and the image height is IH = 0.924mm. Also, H = TT = 5.14mm, D₁= 4.62mm, D₂= 2.62. Therefore, MD / ED = D₁/ D₂= 1.76.

【0122】

The aspherical surface is a rotationally symmetric aspherical surface given by the following definition formula. Z = (y² / R) / [1+ {1- (1 + k) y² / R² }^1/2] + ay⁴ + by⁶ + cy⁸ + dy¹⁰+ ... (16) However, Z is the optical axis (main ray on the axis) with the traveling direction of light as positive, and y is taken in the direction perpendicular to the optical axis. Here, R is the radius of curvature of the near axis, k is the conical constant, and a, b, c, d, ... Are the aspherical coefficients of the 4th, 6th, 8th, and 10th orders, respectively. The Z axis of this definition formula is the axis of the rotationally symmetric aspherical surface. The term related to the aspherical surface for which no data is described is 0.

【0123】<img file="JP2004088713A_D0009.tif" />As can be seen from FIG. 27, the image pickup lens unit of this embodiment has good aberration characteristics in the visible light region. In this embodiment, TT and MD / ED satisfy the equations (13) and (15), respectively. The result is an imaging lens unit with excellent cutting processability.

【0125】

[Example 10]

FIG. 28 is an optical path diagram of the tenth numerical embodiment. FIG. 29 is an aberration diagram of this embodiment. Since FIGS. 29 (a), (b), and (c) are drawn in the same manner as the graphs described in FIGS. 10 (a), (b), and (c), the explanation of the graph axes and the like is omitted. To do. In addition, H and D shown in the figure₁, D₂Is the same amount as described in FIG.

【0126】

The configuration of this embodiment is, in order from the object side, a first lens 92 having negative power, a second lens 93 having positive power, a third lens 94 having positive power, a brightness diaphragm 89, and a fourth lens having positive power. It includes a lens 95, a spacer 56, and filter members 54 and 55. Then, in this order, the first lens 92 to the fourth lens 95, which need to align the optical axes, are manufactured by being joined to each other and then cut into regular quadrangular prisms. The third lens 94 is provided with a positioning protrusion 94e, and an air gap is formed between the third lens 94 and the second lens 93. The brightness diaphragm 89 forms an air gap between the third lens 94 and the fourth lens 95, and the aperture diaphragm portion 89a is arranged in the middle thereof. The spacer 56 forms an air gap between the fourth lens 91 and the filter member 54. In this embodiment, the object point distance is set to So = 340 mm and the hyperfocal length is set. The focal length is f = 1.67mm, the total diagonal angle of view is ω = 60 °, the effective F number is F2.8, and the image height is IH = 0.924mm. And H = TT = 5.80mm, D₁= 5.42mm, D₂= 3.62. Therefore, MD / ED = 1.50. The following aspherical type is the formula (16) described in the ninth embodiment.

【0127】<img file="JP2004088713A_D0010.tif" /> 【0128】

As can be seen from FIG. 29, the image pickup lens unit of this embodiment has good aberration characteristics in the visible light region. In this embodiment, TT and MD / ED satisfy the equations (13) and (15), respectively. As a result, the lens has excellent cutting processability.

【0129】

[Example 11]

FIG. 30 is an optical path diagram of the eleventh numerical embodiment. FIG. 31 is an aberration diagram of this embodiment. Since FIGS. 31 (a), (b), and (c) are drawn in the same manner as the graphs described in FIGS. 10 (a), (b), and (c), the explanation of the graph axes and the like is omitted. To do. In addition, H and D shown in the figure₁, D₂Is the same amount as described in FIG.

【0130】

In this embodiment, the first lens 96 having negative power, the brightness aperture 89, the second lens 97 having positive power, the third lens 98 having positive power, the spacer 56, and the filter member 54 are arranged in this order from the object side. , 55 equipped. Then, in this order, the first lens 92 to the fourth lens 95, which need to align the optical axes, are manufactured by being joined to each other and then cut into regular quadrangular prisms. The brightness diaphragm 89 forms an air gap between the first lens 96 and the second lens 97, and the aperture diaphragm portion 89a is arranged in the middle thereof. The third lens 98 is provided with a positioning protrusion 98e, and an air gap is formed between the third lens 98 and the second lens 97. The spacer 56 forms an air gap between the third lens 98 and the filter member 54. In this embodiment, the object point distance is set to So = 440 mm and the hyperfocal length is set. The focal length is f = 1.88mm, the total diagonal angle of view is ω = 50 °, the effective F number is F2.8, and the image height is IH = 0.924mm. And H = TT = 4.67mm, D₁= 3.58mm, D₂= 2.18 mm. Therefore, MD / ED = 1.64. The following aspherical type is the formula (16) described in the ninth embodiment.

【0131】<img file="JP2004088713A_D0011.tif" /> 【0132】

As can be seen from FIG. 31, the image pickup lens unit of this embodiment has good aberration characteristics in the visible light region. In this embodiment, TT and MD / ED satisfy the equations (13) and (15), respectively. As a result, the lens has excellent cutting processability.

【0133】

[Example 12]

FIG. 32 is an optical path diagram of a twelfth numerical embodiment in which a zoom lens optical system is configured by using the image pickup lens unit according to the first embodiment of the present invention. FIG. 32 is an optical path diagram on the wide-angle side (abbreviated as W). FIG. 33 (a) is an optical path diagram of the same intermediate angle of view (abbreviated as S), and FIG. 33 (b) is an optical path diagram of the most telephoto side (abbreviated as T). 33, 34, and 35 are aberration diagrams in the lens arrangements of W, S, and T, respectively, in this embodiment. Figures 33 to 35 show FIG. 10 (a), except that the vertical axis of astigmatism (each figure (b)) and distortion (each figure (c)) are shown in image height (unit: mm). ), (B), and (c) are drawn in the same manner as the graphs described, so the description of the graph axes and the like is omitted. In addition, H shown in the figure₁, H₂Is the same amount as H explained in Fig. 7, and D₂Is the same amount as described in FIG. In this embodiment, all the lens groups are cut as regular hexagonal prisms, and D.₁Is equal to the diameter of the circumscribed cylinder of a regular hexagonal prism.

【0134】

The configuration of this embodiment includes a first lens group G1 having negative power, a second lens group G2 having positive power, a third lens group G3 having positive power, and a filter member 54 in order from the object side. .. Then, by moving the first lens group G1 and the second lens group G2, it is possible to change the magnification by about 2 times. The first lens group G1 is composed of the first lens 211. The second lens group G2 is manufactured by cutting the second lens 212 made of an uneven lens, the brightness diaphragm 89, and the third lens 213 made of a biconvex lens from the object side after being joined to each other in this order. Due to the brightness diaphragm 89, an air gap is formed between the second lens 212 and the third lens 213, and an aperture diaphragm portion 89a is formed in the middle. In the third lens group G3, from the object side, a fourth lens 214 made of an uneven lens and a fifth lens 215 made of a convex flat lens are joined by a positioning protrusion 215e provided on the fifth lens 215 with an air gap. It has been disconnected since then.

【0135】

In this embodiment, the object point distance is set to So = 900 mm and the hyperfocal length is set. Focal length is f = 1.53mm (W) ~ 2.19mm (S) ~ 2.99mm (T), total diagonal angle of view is ω = 31.2 ° (W) ~ 22.9 ° (S) ~ 17.2 ° (T), effective The F number is F2.73 (W) to F3.28 (S) to F3.97 (T), and the image height is IH = 0.924mm. Then, H, which is the TT of the second lens group G2 and the third lens group G3.₁, H₂Is H₁= 2.17, H₂= 1.30. Also, D₁= 4.84mm, D₂= 4.00 mm. Therefore, MD / ED = 1.21. The following aspherical type is the formula (16) described in the ninth embodiment. Further, in the configuration parameter table shown below, for the sake of simplicity, the values at the time of scaling are collectively indicated in the form of W to S to T.

【0136】<img file="JP2004088713A_D0012.tif" /><img file="JP2004088713A_D0013.tif" /> 【0137】

As can be seen from FIGS. 34 to 36, the zoom lens of this embodiment has good aberration characteristics in the visible light region. In this embodiment, the TT and MD / ED of the image pickup lens unit forming the second lens group and the third lens group satisfy the equations (13) and (15), respectively. As a result, it is composed of an image pickup lens unit having excellent cutting processability.

【0138】

In the description of the imaging lens unit showing the 9th to 11th numerical examples above, it is assumed that the optical element, the aperture diaphragm, etc. that need to align the optical axis are joined and cut, and the length of the TT is also the same. However, it goes without saying that other sandwiching members such as spacers and optical filter members may be cut in a joined state if necessary. Even in that case, the 9th to 11th numerical examples described above are examples in which TT satisfies the equation (13).

【0139】

[Second Embodiment]

Next, the image pickup apparatus of the second embodiment according to the present invention will be described. The image pickup apparatus of the present embodiment includes the image pickup lens unit according to the first embodiment. Hereinafter, a specific example will be described.

【0140】

FIG. 37 is an explanatory diagram showing a schematic configuration of an optical system of the zoom lens 200, which is an example of the image pickup apparatus according to the present embodiment. From the object side, the zoom lens 200 includes a first group G1 having a positive power, a second group G2 having a negative power, a third group G3 having a positive power, a fourth group G4 having a positive power, a filter member, and the like. The fifth group G5 is provided, and each is attached to a mirror frame (not shown), and the second group G2, the third group G3, and the fourth group G4 are movably held with respect to the first group G1. The movable second group G2 and third group G3 are composed of the image pickup lens units 201 and 202 according to the first embodiment of the present invention. The imaging lens units 201 and 202 each have a configuration in which three lenses are joined to each other in the optical axis direction without using a mirror frame. And it has one air spacing and one joint surface.

【0141】

Next, FIG. 38 is an optical axis sectional view showing a schematic configuration of an imaging unit 900 used in the imaging apparatus according to the present embodiment. As shown in FIG. 38 (a), the image pickup unit 900 includes an image pickup lens unit 150 and an image pickup element 901. In this example, the image pickup lens unit 150 is integrated by joining three lenses at a flange portion, but all the image pickup lens units according to the first embodiment of the present invention can be adopted. The image sensor 901 includes a CCD902 and a microlens 903, which are photoelectric conversion devices formed on a semiconductor wafer. Then, the microlens array 903 is formed on the light receiving surface of the CCD 902. The image pickup lens unit 150 and the cover glass 904 are adhesively fixed to each other with an adhesive 906 via a spacer 905. The spacer 905 has a shape such as a wedge shape so that the position and inclination of the image pickup lens unit 150 in the optical axis direction and the distance from the cover glass 904 can be adjusted. There is.

【0142】

Figure 38 (b) shows an example of another imaging unit 900'. The image pickup unit 900'uses another image pickup lens unit 151 instead of the image pickup lens unit 150. The image pickup lens unit 151 includes a plurality of positioning protrusions 151a on the flange portion of the optical element arranged on the final surface on the image side. The spacer 905 is omitted due to the positioning protrusion 51a. Further, the image pickup unit 900'is an example configured by using the image pickup device 910 provided with the CCD902 and the microlens array 903 and without the cover glass 904 instead of the image pickup element 901.

【0143】

FIG. 38 (c) shows an example of yet another image pickup unit 900 ". The image pickup unit 900" is provided with a positioning protrusion 152a on a flange portion or the like of an optical element arranged on the final surface on the image side. It is equipped with an image pickup lens unit 152 and an image pickup element 910. The outer peripheral portion of the CCD902 is aligned with the flange side surface 152c (side surface). Such a configuration can be easily manufactured by using a method of stacking and joining optical element arrays and then cutting the image pickup lens unit 152. That is, the bonded optical element array is positioned with respect to the semiconductor wafer in which the CCD902 is formed in an array, the positioning protrusion 152a is adhered to the semiconductor wafer by the adhesive 906, and the optical element array and the semiconductor wafer are cut at the same time. It can be manufactured by doing.

【0144】

A specific example of the image pickup apparatus according to the present embodiment using the image pickup unit 900 will be described below. FIG. 39 shows an example in which the imaging unit 900 is used for the capsule endoscope 300. The capsule endoscope 300 includes an illumination light source 304, an image pickup unit 900, an image processing circuit 302 that processes signals from the image pickup elements of the image pickup unit 900, and a battery 301 that supplies power to them, and is entirely covered with a cover 303. ing. A transparent window 305 is provided at the tip of the cover 303. The illumination light is projected and the reflected light is received by the image pickup unit 900 through the transparent window 305.

【0145】

Next, FIG. 40 shows an example in which the image pickup unit 900 is used for the portable terminal 400. 40 (a) and 40 (b) are front views and side views, respectively, and FIG. 40 (c) is a CC sectional view of FIG. 40 (a). The portable terminal 400 includes an image pickup unit 405 using the image pickup unit 900, a monitor unit 404, an input unit 403 for inputting character symbols and command signals with buttons and dials, a microphone unit 401, a speaker unit 402, and wireless communication. It is equipped with an antenna 406 to perform. As shown in FIG. 40 (c), inside the portable terminal 400, the CCD902 included in the image pickup unit 900 is electrically connected and fixed on the circuit board 409 fixed to the board mounting portion 410. A cover glass 405 is provided and sealed in the direction of the optical axis 407 of the imaging unit.

【0146】

Next, FIG. 41 shows an example in which the imaging unit 900 is used in the personal computer 500. FIG. 41 is a perspective explanatory view for explaining a schematic configuration of the personal computer 500. The personal computer 500 includes a keyboard 501, a monitor unit 502, and an imaging unit 503. The monitor unit 502 is configured to be capable of displaying an image 505 including an image taken by the imaging unit 503. The image pickup unit 503 is provided next to the monitor unit 502. The image pickup unit 900 (not shown) is provided inside the image pickup unit 503, and has the same configuration as shown in FIG. 40 (c) in cross section in the optical axis direction.

【0147】

Next, FIG. 42 shows an example in which the imaging unit 900 is used for the surveillance camera 600. FIG. 42 is a side view explanatory view for explaining the schematic configuration of the surveillance camera 600. The surveillance camera 600 includes a circuit unit 605 and an imaging unit 607 that form the main body of the surveillance camera, and is attached to a mounting portion 601 fixed to the ceiling 608 via a shaft 602 and a motor 603. An imaging unit 900 is provided inside the imaging unit 607 so that imaging can be performed in the direction of the straight arrow shown in the drawing. The image pickup unit 900 has the same configuration as that shown in FIG. 40 (c) in the cross section in the optical axis direction, and is fixed in the image pickup unit 607. The board mounting portion 410 (see FIG. 40 (c)) may be mounted so as to be swingable by a rotation mechanism (not shown).

【0148】

Next, FIG. 43 shows an example in which the imaging unit 900 is used in the in-vehicle camera system 700 of an automobile. FIG. 43 is a perspective explanatory view for explaining a schematic configuration of the in-vehicle camera system 700. The in-vehicle camera system 700 is a system provided with imaging units 704a, b, and c so that images taken by the respective imaging units can be displayed on the monitor unit 701 via the signal processing unit 702 and the switching control unit 703. is there. The imaging units 704a, b, and c are connected by optical fibers 705a, b, and c, respectively. The image pickup unit 900 has the same configuration as that shown in FIG. 40 (c) in the optical axis direction cross section, and is fixed in the image pickup units 704a, b, and c.

【0149】

According to the image pickup apparatus according to the present embodiment described above, since the image pickup lens unit according to the first embodiment of the present invention is used, the same effects as those of the image pickup lens unit according to the first embodiment are used. Play. In particular, according to the zoom lens 200, since the lens groups of the second group G2 and the third group G3 are integrated without using a mirror frame, it is possible to reduce the weight and size. Further, according to the imaging unit 900, it is possible to manufacture a configuration integrated with the CCD902 by a common manufacturing method of stacking and joining the constituent members, so that there is an advantage that productivity is good because the manufacturing process is consistent. is there. Further, according to the method of joining each of them in an array-like arrangement and then cutting out, there is an advantage that productivity is further improved and it is suitable for mass production and miniaturization.

【0150】

[Effect of the invention]

As described above, according to the image pickup lens unit according to the present invention, the optical elements are integrated without providing a mirror frame member or a mirror frame structure while improving the performance of the optical system by providing an air spacing. This has the effect of providing a compact and inexpensive imaging lens unit. Further, according to the image pickup apparatus according to the present invention, since the image pickup lens unit according to the present invention is used, the same effect as that of the image pickup lens unit according to the present invention can be obtained.

[Simple explanation of drawings]

FIG. 1 is a schematic perspective view and an AA cross-sectional view thereof for explaining the image pickup lens unit according to the first embodiment of the present invention.

FIG. 2 is a schematic perspective view for explaining an example for manufacturing an imaging lens unit according to the first embodiment of the present invention.

FIG. 3 is a perspective explanatory view for explaining the first modified example, a BB sectional view thereof, and a conceptual diagram of an optical axial cross section for explaining an example of a manufacturing method of the present modified example.

FIG. 4 is a cross-sectional view in the optical axis direction for explaining the second modification and a conceptual diagram of the cross section in the optical axis for explaining an example of a manufacturing method of the present modification.

FIG. 5 is a cross-sectional view in the optical axis direction for explaining the third modification, and a conceptual diagram of the cross section in the optical axis for explaining an example of a manufacturing method of the present modification.

FIG. 6 is a cross-sectional view in the optical axis direction for explaining the fourth modification, and a conceptual diagram of the cross section in the optical axis for explaining an example of a manufacturing method of the present modification.

FIG. 7 is a cross-sectional view in the optical axis direction for explaining the fifth modification, and a conceptual diagram of the cross section in the optical axis for explaining an example of a manufacturing method of the present modification.

FIG. 8 is an explanatory diagram showing an example of a cut shape of the optical element array according to the first embodiment of the present invention.

FIG. 9 is an optical path diagram of a first numerical embodiment of the image pickup lens unit according to the first embodiment of the present invention. FIG. 10 is an aberration diagram of the first numerical embodiment.

FIG. 11 is an optical axis sectional view illustrating a means for forming an air gap in the configuration of the first numerical embodiment.

FIG. 12 is an optical path diagram of a second numerical embodiment of the image pickup lens unit according to the first embodiment of the present invention. FIG. 13 is an aberration diagram of the second numerical embodiment.

FIG. 14 is an optical path diagram of a third numerical example of the image pickup lens unit according to the first embodiment of the present invention.

FIG. 15 is also an aberration diagram of the third numerical example.

FIG. 16 is an optical path diagram of a fourth numerical example of the image pickup lens unit according to the first embodiment of the present invention.

FIG. 17 is an aberration diagram of the fourth numerical example.

FIG. 18 is an optical path diagram of a fifth numerical example of the image pickup lens unit according to the first embodiment of the present invention.

FIG. 19 is an aberration diagram of the fifth numerical example.

FIG. 20 is an optical path diagram of a sixth numerical example of the image pickup lens unit according to the first embodiment of the present invention.

FIG. 21 is an aberration diagram of the sixth numerical example.

FIG. 22 is an optical path diagram of a seventh numerical example of the image pickup lens unit according to the first embodiment of the present invention.

FIG. 23 is an aberration diagram of the seventh numerical example.

FIG. 24 is an optical path diagram of an eighth numerical example of the image pickup lens unit according to the first embodiment of the present invention.

FIG. 25 is also an aberration diagram of the eighth numerical example.

FIG. 26 is an optical path diagram of a ninth numerical example of the image pickup lens unit according to the first embodiment of the present invention.

FIG. 27 is an aberration diagram of the ninth numerical example.

FIG. 28 is an optical path diagram of a tenth numerical embodiment of the image pickup lens unit according to the first embodiment of the present invention.

FIG. 29 is also an aberration diagram of the tenth numerical embodiment.

FIG. 30 is an optical path diagram of an eleventh numerical embodiment of the image pickup lens unit according to the first embodiment of the present invention.

FIG. 31 is an aberration diagram of the eleventh numerical embodiment.

FIG. 32 is an optical path diagram of the image pickup lens unit according to the first embodiment of the present invention at the W position of the twelfth numerical embodiment.

FIG. 33 is an optical path diagram at S and T positions of the twelfth numerical embodiment.

FIG. 34 is an aberration diagram (W) of the twelfth numerical embodiment.

FIG. 35 is an aberration diagram (S) of the twelfth numerical example.

FIG. 36 is an aberration diagram (T) of the twelfth numerical example.

FIG. 37 is an explanatory diagram showing a schematic configuration of an optical system of a zoom lens which is an example of an image pickup apparatus according to a second embodiment of the present invention.

FIG. 38 is an optical axis sectional view showing a schematic configuration of an image pickup unit which is a main part of an image pickup apparatus which is another example of the image pickup apparatus according to the second embodiment of the present invention.

FIG. 39 is a cross-sectional explanatory view showing a schematic configuration of a capsule endoscope using the imaging unit.

FIG. 40 is a front view, a side view, and a cross-sectional view showing a schematic configuration of a portable terminal using the imaging unit.

FIG. 41 is a perspective explanatory view showing a schematic configuration of a personal computer using the imaging unit.

FIG. 42 is a side view explanatory view showing a schematic configuration of a surveillance camera using the imaging unit.

FIG. 43 is a perspective explanatory view showing a schematic configuration of an in-vehicle camera system of an automobile using the imaging unit.

[Explanation of symbols]

1, 2, 4, 11, 12, 13, 21, 22, 24, 25 Lenses (optical elements) 1a, 1b, 2a, 2b, 4a, 4b, 11a, 11b, 12a, 12b, 13a, 13b, 21a, 21b, 22a, 22b, 24a, 24b, 25a, 25b Lens surface (optical surface) 1c, 2c, 3c, 4c, 11c, 12c, 13c, 21c, 22c, 24c, 25c, 152c Flange side surface (side surface) 1d, 2d , 3d, 4d, 11d, 12d, 13d, 21d, 22d, 24d, 25d Flange 1e, 2e, 3e, 22e, 24e, 25e, 51a, 52a, 151a Positioning protrusions 2f, 3f, 4f Positioning groove 3 Optical filter ( Optical filter member) 6 Cutting line 23 Open aperture (holding member) 31 Open aperture coat 32 Flare prevention coat 40 Optical surface 41 Hood member 51, 57, 60, 65, 69, 73, 76, 80, 87, 92, 96, 211 1st lens (optical element) 52, 58, 61, 66, 70, 74, 77, 82, 88, 93, 97, 212 2nd lens (optical element) 53, 59, 62, 67, 71, 75, 78, 83, 90, 94, 98, 213 Third lens (optical element) 54, 55 Filter member (optical filter member) 56 Spacer (holding member) 63, 68, 72, 79, 84, 91, 95, 214 4th lens (optical element) 81 Parallel flat plate 85, 215 5th lens (optical element) 100 , 110, 120, 130, 140, 145, 150, 151, 152, 201, 202 Imaging lens unit 101, 102, 103, 104, 111, 112, 113, 121, 122, 124, 125 array (optical element array) 123 Aperture aperture sheet (holding member) 141 Hood array member 200 Zoom lens (imaging device) 300 Capsule endoscope (imaging device) 400 Portable terminal (imaging device) 405, 503, 607, 704a, 704b, 704c Imaging unit 500 Personal computer (imaging device) 600 Surveillance camera (imaging device) 700 In-vehicle camera system (imaging device) 900, 900', 900 Imaging unit 901, 910 Imaging element 902 CCD