Method for processing information

(54) (56)

INVENTOR'S OFFICE NAME

CALLED PUBLICATIONS:

Linus Wiebe, Lund SE, Petter Ericson, AWAPATENT AB

Ways to handle information

Malmö SE

WO A 9950787 (57) SUMMARY:

The invention relates to a method of generating, in a system comprising a computer unit and a printer unit connected to the computer unit, a printout of a section of an overall position coding pattern. The method is characterized by the steps: generation in the computer unit of boundary information, which describes the boundaries of the section in the overall position coding pattern; transmitting the boundary information from the computer unit to the printer unit; generation in the printer unit by an algorithm defining the overall position coding pattern, and based on the boundary information, of graphical information describing pattern symbols in the section; and printing with the printer unit of the graphic information on a substrate.

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The numbers in brackets indicate international identification code, INID code. Letters in clamps indicate international document code.

<td colspan="4">VPRV Patent uses the following document codes for its patent documents</td><td rowspan="2"></td>

<td>code</td><td>cleartext</td><td>code</td><td>cleartext</td>

<td>A</td><td>widely available patent application</td><td>L</td><td>widely available</td><td></td>

<td>B</td><td>pamphlet *</td><td>TI</td><td>translation of the requirements of European patent application</td><td></td>

<td>B5</td><td>corrected layout letter *</td><td>T2</td><td colspan="2">correction of translation of the requirements of European patent application</td>

<td>C</td><td>patent office *</td><td>T3</td><td>translation of European patent</td><td></td>

<td>Cl</td><td>patent *</td><td>T4</td><td>translation of European patent in amended form</td><td></td>

<td>C2</td><td>patent</td><td>T5</td><td>corrected translation of European patent</td><td></td>

<td>C3</td><td>corrected patent</td><td>T8</td><td>corrected translation of European patent</td><td></td>

<td>C5</td><td>corrected patent *</td><td>T9</td><td>corrected translation of European patent</td><td></td>

<td>C8</td><td>corrected front page to patent</td><td></td><td></td><td></td>

<td>E</td><td>patent in amended version</td><td></td><td></td><td></td>

<td>E8</td><td>corrected front page to patent in amended version</td><td></td><td></td><td></td>

<td>VL</td><td>corrected patent in amended version</td><td colspan="2">* Published under older legislation</td><td>J</td>

ΓMationskoder \

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519 012

Technical area

The present invention relates to a method of generating in a system comprising a computer unit and a printer unit associated with the computer unit 5 a print of a position coding pattern according to the preamble of claim 1, a system for generating a print of a position coding pattern according to the preamble of claim 18, a printer device according to the preamble of claim 19, 10, a computer program according to the preamble of claim 22, a digital storage medium according to claim 23 and a printer according to claim 24.

Background of the invention

The present invention is intended to be utilized in the generation of position coding patterns. A position coding pattern is made up of a large number of symbols, which are printed on a substrate. By optically registering a certain minimum number of symbols with a locking device, the absolute position of these symbols, and thus the locking device, in the pattern can be detected.

Such a pattern can be used in different ways. For example, a locking device may be integrated into an ink pen used for writing on the substrate. As soon as the user writes a text or figure on the substrate, the movement of the pen over the substrate can then be recorded as a result of positions. Thus, a digital copy of what the user has written on the substrate can be created, without the use of a regular scanner.

The position coding pattern can be designed in a variety of ways. It has been suggested that symbols in the form of dots of different sizes can be utilized, with a larger dot encoding one and a smaller dot encoding a

519 012

<img file="SE519012C2_D0002.tif" />

zero. Such a pattern is shown in WO 00/73983, which is incorporated in the present application by this reference. Alternatively, points with different offsets relative to a raster can encode different symbol values. Such patterns are shown in WO 01/16691, PCT / SE00 / 01895 and PCT / SE00 / 01897, which are incorporated in the present application by this reference.

Such a position coding pattern can, with good resolution, encode unique positions on a very large surface. 10 It is estimated that 4.6 million km² can be coded with unique positions good resolution.

In many contexts, substrates with position coding patterns can be generated on a large scale and with high precision in the graphic industry. This applies, for example, to the production of almanacs or notepads. However, there are also contexts where it is desirable to create substrates with position coding patterns on a small scale. This can then be done with the aid of a personal computer to which a printer unit of, for example, ink-jet or laser type has been connected.

This can be done so that the desired part of the position coding pattern is created as a file in a graphical format, for example in bmp format (bmp = bitmap). This graphic is translated into a page description and usually printer-independent code, such as, for example, POSTSCRIPT (trademark), after which it is sent to the printer unit. The printer unit, on the basis of the page descriptive code, creates corresponding information, which is used to control the printer's hardware. This hardware, in the case of a laser printer, may include a laser diode with associated optics. In case the printer is an ink jet printer, the hardware comprises an ink ejector. Printing is then done on a substrate, such as a sheet of paper.

One problem associated with this procedure is that the system in the resulting print introduces something that could be called noise. This noise arises as a result of, among other things, quantisations and results

519 012 small displacements and / or deformations of the symbols in the position coding pattern. The quantization occurs when the graphic file is adapted to the page descriptive code and / or when the page descriptive code is adapted to the printer's hardware and software.

When printing graphic files that describe other than position coding patterns, such as images intended to be viewed by a human eye, this normally does not pose a problem. Small displacements or deformations of 10 small elements in an image are usually not detected.

However, for a locking device of the aforementioned type, which is intended to detect positions in a position coding pattern, such offsets and deformations of the symbols in the pattern may pose problems by reading the device detecting an incorrect or invalid position. This can happen if the position coding pattern's resolution is too high in relation to the printer's performance and the quality (for example, surface smoothness) of the substrate.

Summary of the Invention

It is an object of the present invention to remedy the foregoing problems in whole or in part.

This object is achieved by a method of generating, in a system comprising a computer unit and a printer unit connected to the computer unit, a print of a position coding pattern according to claim 1, a system for generating a print of a position coding pattern according to claim 18, a printer device according to claim 30, a computer program according to claim 22, a digital storage medium according to claim 23 and a printer according to claim 24.

According to a first aspect of the invention, this relates to a method of generating, in a system comprising a computer unit and a printer unit connected to the computer unit, a printout of at least one section of an overall position coding pattern. The method is characterized by the steps:

<img file="SE519012C2_D0003.tif" />

generating boundary information in the computer unit describing the boundaries of the section in the overall position coding pattern; transmitting the boundary information from the computer unit to the printer unit; to generate in the printer unit an algorithm defining the overall position coding pattern and to generate graphical information describing pattern symbols in the section based on the boundary information; and with the printer unit to print the graphic information on a substrate. This allows the printed pattern to be matched to the printer's characteristics, allowing printing of position coding patterns with greater precision.

In a preferred embodiment, the method further comprises the step of transferring the algorithm from the computer unit to the printer unit. This allows printing of a pattern generated in the printer unit even if it is not specifically equipped for printing them.

Preferably, a plurality of sections, which may be derived from separate portions of the overall position coding pattern, can be printed on one and the same substrate. Then several sets of boundary information are transmitted from the computer unit to the printer unit. This allows printing of more complex pattern compositions.

The pattern symbols may preferably be dots. This allows printing of designs with very high resolution.

Preferably, the computer unit transmits a desired pattern quality measure to the printer unit, the printer unit adapting a set of printer parameters (e.g., dot size) on the basis of the pattern quality measure using the algorithm. This enables printer-independent printing of higher quality position coding patterns. A pattern of good quality can be generated autonomously. The printer unit can be equipped with optical equipment that checks the quality of the printed pattern and controls the parameters accordingly until the quality measure is reached.

519 012

In a preferred embodiment, the algorithm is so arranged that the distances between the pattern symbols in the graphical information are dependent on a printer parameter. This can be used to completely or partially eliminate quantization noise, which occurs if the printer does not have very high resolution.

According to a preferred embodiment, the algorithm is so arranged that the pattern symbols in the graphical information are offset relative to each other by multiples of the smallest possible symbol offset of the printer unit.

This gives an optimal pattern at the given resolution of the printer unit.

When printing where a position coding pattern scale is adjusted to an ideal pattern, the printer unit is preferably arranged to also adjust the scale of printed information, which is not a position coding pattern. This provides better printouts when the interrelationship of positions in a position coding pattern with positions in other types of printouts is important.

Preferably, the algorithm is so arranged that the size of the pattern symbols in the graphical information depends on a parameter specific to the printer. This provides printed position coding patterns with higher quality.

According to a preferred embodiment, the algorithm is so arranged that the intensity of the pattern symbols in the graphical information depends on a parameter specific to the printer. This provides printed position coding patterns with higher quality.

Preferably, the printer unit operates at print speed at a reduced print speed compared to the printer's maximum print speed. This provides printed position coding patterns with higher quality.

If a section of a position coding pattern is in the form of a flat curve, the corresponding boundary information preferably comprises a parameter representation of

519 012 this curve. This provides an opportunity to easily describe a section in a position coding pattern.

According to one embodiment of the invention, at least one section has the shape of a rectangle, the corresponding boundary information comprising at least positions in the position coding pattern for two diagonally opposite corners of the rectangle. This provides an opportunity to easily describe a section in a position coding pattern.

According to one embodiment of the invention, at least one section is in the form of a polygon, the corresponding boundary information comprising at least positions in the position coding pattern for vertices in the polygon. This provides an opportunity to easily describe a section in a position coding pattern.

According to one embodiment of the invention, at least one section is in the form of a circle, the corresponding boundary information comprising at least the position in the position coding pattern of the center of the circle and a data regarding the diameter of the circle. This provides an opportunity to easily describe a section in a position coding pattern.

According to one embodiment of the invention, at least one section is in the form of an ellipse, the corresponding boundary information comprising at least positions in the position coding pattern of the ellipse's focal points and an indication of the total distance between one of each of the focal points and, on the other hand, a given point of the ellipse. periphery. This provides an opportunity to easily describe a section in a position coding pattern.

According to a second aspect of the invention, this relates to a system comprising a computer unit and a printer unit connected to the computer unit for generating a printout of at least one section of an overall position coding pattern. The system is characterized by means in the computer unit for generating boundary information, which

519 012 describes the boundaries of the section in the overall position coding pattern; means for transmitting the boundary information from the computer unit to the printer unit; means in the printer unit for generation by means of an algo5 rhythm defining the overall position coding pattern, and on the basis of the boundary information, of graphical information describing pattern symbols in said section; and means in the printer unit for printing said graphic information on a substrate. This system has similar advantages as the method and can be varied accordingly.

According to a third aspect of the invention, this relates to a printer device for generating a printout of at least one section of an overall position coding pattern, the printer being intended to be connected to a computer unit. The printer device is characterized by means for receiving from the computer unit by boundary information which describes the boundaries of the section in the overall position coding pattern; means for generating, by means of an algorithm defining the overall position coding pattern, and on the basis of the boundary information of graphical information describing pattern symbols in said section; and means for printing said graphical information on a basis. This device provides similar advantages to the method and can be varied accordingly.

Preferably, in the printer device, graphic information corresponding to a position coding pattern with a color that absorbs infrared light is printed, and other graphic information is printed with a color that does not absorb infrared light. This allows the position coding pattern to be detected with infrared light without being disturbed by other graphical information such as text or figures on the same sheet.

According to a preferred embodiment, the printer unit comprises a paper tray intended for paper sheets which are adapted for printing position coding patterns. This allows easy use of high quality sheets when printing position coding patterns.

According to a fourth aspect of the invention, this relates to a computer program intended to generate in a system comprising a computer unit and a printer unit connected to the computer unit a printout of at least one section of an overall position coding pattern. The computer program is characterized by instructions corresponding to the steps:

generating, boundary information, which describes the boundaries of the section in the overall position coding pattern; transmitting the boundary information from the computer unit to the printer unit, wherein the printer unit is intended, by means of an algorithm defining the overall position coding pattern, and on the basis of the boundary information, to generate graphical information describing pattern symbols in said section, and to print said graphical information on a basis . This program provides similar advantages to the method and can be varied in a corresponding manner.

According to a fifth aspect of the invention, this relates to a digital storage medium containing such a computer program.

According to a sixth aspect of the invention, this relates to a printer for printing visual information where the printer is intended to be connected to a computer unit. The printer is characterized by an actuator, such as a button, provided on the printer. Activation of the actuator activates an algorithm in the printer, which algorithm generates graphical information corresponding to a position coding pattern, whereby this graphical information is printed upon the said visual information. This allows the addition of a position coding pattern to any graphic or text document.

In a preferred embodiment, the printer is arranged to retrieve boundary information from a computer system associated with the printer, which boundary information is used.

519 012 of said algorithm. Using such a system, it can be guaranteed that a position coding pattern unique to a group of users is printed by the printer unit.

Short figure description

Fig. 1 shows a system in which the present invention can be utilized.

Fig. 2 shows a position coding pattern of a first type.

Fig. 3 shows a position coding pattern of a second type.

Fig. 4 shows in block diagram form an arrangement for printing a position coding pattern.

Fig. 5 shows in block diagram form an arrangement for printing a position coding pattern according to an embodiment of the invention.

Fig. 6 illustrates a problem of quantizing symbol size.

Fig. 7 illustrates a problem of fast printing in inkjet printers.

Fig. 8 illustrates a problem of quantizing symbol offset spacing.

Fig. 9 shows a flow chart for a method according to an embodiment of the invention.

Description of preferred embodiments

Fig. 1 shows a system 100 in which the present invention can be utilized. The system comprises a computer unit, such as a personal computer 103, which normally has a display 104 and a keyboard 105. The personal computer 103 is connected to a printer unit 106 by, for example, a cable 107. The system is used for printing a position coding pattern on a sheet. While the position coding pattern is being printed, other information can be printed on the sheet.

Fig. 2 shows a position coding pattern of a first type printed on a sheet 200. In this pattern

<img file="SE519012C2_D0004.tif" />

<img file="SE519012C2_D0005.tif" />

<img file="SE519012C2_D0006.tif" />

different dots are used to encode different symbol values. For example, a large dot 202 can encode a logical one and a small dot 201 a logical zero. By optically detecting symbol values ​​within a region of 203 with a certain minimum area, the position of the region in the overall pattern and thus on the sheet 200 can be unambiguously determined.

This can, for example, be utilized in a drawing device (not shown) in the form of a pen equipped with an optical detector. The drawing device can be used to write, for example, a text on the sheet. At the same time, the optical detector detects a sequence of positions on the sheet by regularly taking pictures of the pattern located under the drawing device. This sequence of positions is a digital copy of the text written on the sheet. Fig. 3 shows a position coding pattern of a second type. In this case, different offsets of points in relation to a grid pattern encode different symbol values. The grid pattern consists of vertical and horizontal bars 301. However, in a real application, the grid pattern 20 does not need to be printed. A point symbol value can also be determined using other points in the pattern. As can be seen in Fig. 3, there are points above, below, to the right and to the left of the corresponding raster position (ie a cross between a vertical and a horizontal line), so there are four different symbol values ​​in this pattern. This pattern can be utilized in a similar way to the pattern in Figure 2.

The distances between two adjacent raster positions in the pattern of Fig. 3 can be 300pm. The dots may be 30 µm 50 pushed from the respective raster position. This gives a minimum distance between two adjacent points (the left offset to the right, the right offset to the left) of 200μπι. The next smallest distance between two points (for example: the left offset to the right, the right offset upwards) becomes 255μτη, given that all points are offset by their respective raster positions. The difference between the smallest and the next smallest distance 519 012 it shrinks if the offsets from the raster positions become larger or the distances between the raster positions decrease, giving less reliable detection.

Fig. 4 shows in block diagram form a print arrangement 5. The event is of a conventional type. Then there is a computer unit 401 and a printer unit 402. These are connected to a cable 408. In the computer, an application 403 is active. If application 403 initiates printing of a position coding pattern, instructions for this are sent to a module 404 for generating position coding pattern. This generates a graphic file, for example in .gif, -jpeg-, .bmp, or .tiff format. This file can be said to contain an ideal pattern. The graphic file is sent to a translation module 405, which in a known manner translates the graphic format into a page descriptive code, for example in POSTSCRIPT ™ format. By means of an I / O (in / out) module 406 in the computer unit 401, the page descriptive code is transmitted via the cable 408 to a corresponding I / O module 409 in the printer unit 402. The page descriptive code then passes to a translation module 410, which translates it into graphical information, which is input to the printer's hardware 412. This graphic information is fed to a buffer memory 411, from which it is read by the printer hardware 412. On the basis of the graphic information it generates the printer hardware 412 prints on a sheet of paper, for example.

Fig. 5 shows in block diagram form an arrangement for printing a position coding pattern according to an embodiment of the invention. The arrangement includes a computer unit 501 and a printer unit 502. In the computer unit

501 Here, the application operates an application 503. The application here initiates printing of a section of a position coding pattern by sending instructions to a boundary module 504. The boundary module 504 then generates information regarding the boundaries of the section in a larger overall position coding pattern. The boundary module 504 may further generate information relating to this section

519 012 ideal resolution and ideal density. The information generated by the boundary module 504 is transmitted to the printer unit 502 via, for example, a cable 506 and by means of an I / O module 505. It will be appreciated that the transmission may be by other means such as, for example, an IR link or a short-held radio link. The transmitted information is received by an I / O module 507 in the printer unit 502 and forwarded to an algorithm module 508 in the printer unit. The algorithm module 508, based on the information from the boundary module 504 of the computer unit 501, generates graphical information describing pattern symbols in the section of the overall position coding pattern. Since the algorithm module 508 has access to data 510 regarding the characteristics of the printer, such as, for example, resolution, ink type, etc., optimal graphical information describing pattern symbols can be generated and fed to a buffer memory 509. As a result, problems described in more detail below can be avoided in whole or in part. Furthermore, the transfer from computer unit to printer unit becomes faster since less information needs to be transmitted when the pattern is generated in the printer unit.

As in the arrangement of Fig. 4, a printer hardware 511 in the printer unit 502 generates a print based on the information in the buffer memory 509. Preferably, the position coding pattern is printed with a color that absorbs infrared light, and other graphic information with a color that does not absorb infrared light. For example, in an ink jet printer, the position coding pattern can be printed with a carbon-based black color while other information is printed with an RGB (Red Green Blue) combination (or CMY combination), which produces a black color that does not absorb IR light. This can be done with color cartridges existing in many inkjet printers and allows the position coding pattern to be detected with infrared light without being disturbed by other graphical information such as text or figures on the same sheet.

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The printer unit may comprise a paper tray intended for paper sheets adapted for printing position coding patterns. If a printout includes a position coding pattern, the printer automatically selects paper from that tray. This allows easy use of high quality sheets when printing position coding patterns.

Of course, a printer arrangement as shown in Fig. 5 may include modules for printing, in the usual manner, information other than position coding patterns. The arrangement may therefore also include modules for generating and translating page descriptive code, which operate in whole or in part in parallel with and independently of the arrangement in Fig. 5. However, insofar as the other information includes parts whose positions on the sheet relative to the position coding pattern are critical, these parts can also be adapted to the position coding pattern.

The algorithm module 508 can be designed in a variety of ways. It can be a system that mathematically calculates the appearance of the pattern based on the boundary information.

It is also possible to include the algorithm module 508 with a memory containing information regarding the appearance of a major or minor part of the position coding pattern.

In general, the modules shown in Figure 5 may comprise both hardware and software.

In principle, it is possible to obtain boundary information from anywhere other than the computer unit that prints other visual information (for example, a text, a figure, a table, or the like) on the printer. The printer may then have an actuator, such as a button, for example. Activation of the control means activates the printer's algorithm (possibly it can be permanently activated), which without this being initiated by the computer unit generates graphical information corresponding to a position coding pattern. This graphic information is overlaid upon printing the visual information. Preferably then

519 The printer may be configured to obtain boundary information from a computer system connected to the printer, which may be other than the aforementioned computer unit. The boundary information is used by the algorithm in the printer. This allows a local (for example, in a workplace) unique pattern to be used in printing, which eliminates the risk of collision in the pattern during digital registration, which is performed using the pattern.

Fig. 6 illustrates a problem of quantizing symbol size. A printer unit may not necessarily generate a point of any size. It is common for a printer to generate a number of different point sizes, which are adapted to the printer's hardware.

Points 601, 602, and 603 provide examples of such. If printing of a position coding pattern is done with a conventional arrangement such as in Fig. 4, there is a risk that the desired ideal symbol size, that is, preferably the spot size, does not match the sizes that can be generated by the printer. Usually, when translating the page descriptive code, these points will be replaced by points with the closest size, ie the size of the points is quantized.

Suppose a pattern of the type shown in Fig. 2 is printed. The larger ideal point 202 has a size that is between the size of points 602 and 603. The less ideal point type 201 has a size that is between the size of points 601 and 602. In a worst case, then the printer unit will print both small and large points in the ideal pattern of size such as point 602. All symbols in such a pattern are given the same symbol value and such a pattern naturally becomes unusable.

Point size quantization can also pose problems in patterns of the type shown in Fig. 3. If the points 35 are made too large, in a high-resolution pattern, they may collapse, which may make optical detection of positions in the pattern impossible.

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If printing is instead done with an arrangement according to the invention, as shown in Figure 5, the pattern of algorithm module 508 can be adapted to the characteristics of the printer. For example, in the example of the pattern of Figure 2, when points 5 of type 601 can be selected to represent small points and points of type 602 may be selected to represent large points.

Fig. 7 illustrates a problem when printing in inkjet printers. The problem arises with fast printing, as the print head moves comparatively fast relative to a sheet of paper. The problem manifests itself as a tail 702 after a point 701. Thus, the point is deformed, which may result in incorrect or missing optical detection of a position in a position coding pattern. In an arrangement according to an embodiment of the invention, this can be avoided by reducing the print speed when printing position coding patterns. This is shown in Fig. 5 where the algorithm module 508 controls the printer hardware 511 to reduce the print speed.

Fig. 8 illustrates a problem of quantizing symbol offset spacing. The resolution at printing varies from printer to printer. By analogy with this, the smallest possible distance varies, a point, for example in a position coding pattern, can be offset. In a printer with a resolution of 800 dpi (dots per inch), the minimum distance a point can be offset is an eight-hundredth inch. This means a restriction on printing. In Figure 8, a number of positions 801, 802, 803 are shown along an axis at which positions a point can be placed. The distance 804 between them is the minimum symbol displacement distance of the printer.

If a point is ideally placed in a position 805 between the above positions, the printer will, upon printing, shift it to any of the possible positions, cf. 806, 807. This implies a quantization of the symbol position. It goes without saying that such offsets »·

519 012 changes of symbol positions can pose problems when printing a position coding pattern as shown in Figure 3.

This is because both a symbol can get an incorrect position relative to its raster position, and that the raster position, which is calculated using the other points in an image of the pattern, is incorrectly calculated. It cannot be assumed that the offset will be similar for all points in the pattern.

If printing is instead done with an arrangement according to the invention, as shown in Figure 5, the pattern of algorithm module 508 can be adapted to the characteristics of the printer.

In the example of the pattern in Fig. 3, the distances between the raster positions and the point displacements relative to the respective raster position can be made into whole multiples of the printer's smallest possible symbol displacement, which gives a printout of a useful pattern.

In one example, a printer with resolution 600dpi is used (giving the minimum offset b = 42.33µm). An ideal pattern of the type shown in Fig. 3 should be printed. This in the example ideally has 300μπι between the raster positions 20 and 50μπι displacement of the points in relation to the raster positions. As mentioned, when printing in a conventional manner in accordance with Fig. 4, uneven displacements of the pattern symbols are given, which, in addition to causing the risk of incorrect position detection, causes disturbing interference patterns in the print.

By adapting the print to the properties of the printer, printing can be improved. The boundary information may include or be accompanied by information defining within which boundaries the pattern may be changed, but such information may also be stored in the printer unit. Preferably, for example, a point offset may be within the range of one eighth to one quarter of the distance between two raster positions. If the resolution of the printer is good, many different conceivable combinations are usually given for selecting raster position and point offset distances. Preferably, the solutions that differ least from the ideal desired pattern are then selected.

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012 • «tt • · * •» * t »

In the distance between breaks (6-b) (unchanged point shift in one embodiment the positions can be changed to 25 µm). Already this adjustment gives a better pattern with significantly less disturbing interference pattern.

In another embodiment, both the spacing between the raster positions and the displacements can be changed. The distance between the raster positions can be changed to 296.33μπι (7-b) and the displacements to 42.33μιη (b). This gives a perfect pattern, without any interferences. Another alternative may be to allow the distance between the raster positions to be changed to 254μιη (6-b) and the offsets to 42.33μιη (b). Note that even a minor adjustment of the raster position and point offset distances from the desired distances can have a positive effect on the printed position coding pattern.

In cases where the offset distances are adjusted downward, it may be advantageous to reduce the point size if necessary, so that the point does not cover its raster position.

Fig. 9 shows a flow chart for a method 900 according to an embodiment of the invention.

In a first step 901, boundary information is generated in the computer unit which describes a section's boundaries in an overall position coding pattern.

If a section is in the form of a flat curve, the boundary information may include one.

If the section is in the form of spirit boundary information, include the coding pattern for two diagonally opposite corners in the rectangle.

If the section is in the form of a polygon, the corresponding boundary information may include positions in the position coding pattern for vertices in the polygon. The polygon need not be equilateral, but if it is equilateral or otherwise symmetrical, a smaller number of position indications is often sufficient than the number of vertices in the polygon.

parameter representation of a rectangle can correspond to positions in position35

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If the section is in the shape of a circle, the corresponding boundary information may include the position in the position coding pattern of the center of the circle and an indication of the diameter of the circle.

If the section is in the form of an ellipse, corresponding boundary information may include positions in the position coding pattern of the ellipse focal points and an indication of the total distance between, on the one hand, each of the focal points and, on the other hand, a given point on the periphery of the ellipse.

In a second step 902, the boundary information is transmitted from the computer unit to the printer unit. Along with the boundary information, information regarding other properties of the pattern can be transmitted, for example, point size.

Multiple sections can be printed on the same surface. Then several sets of boundary information are transmitted from the computer unit to the printer unit. The different sections can be derived from separate parts of the overall position coding pattern.

A third step 903 is generated in the printer unit by an algorithm defining the overall position coding pattern, and based on the boundary information graphic information describing pattern symbols in the section. Optionally, the algorithm can also be transferred from the computer unit to the printer. The algorithm can then be written in a page descriptive code.

In a fourth step 904, the graphic information is printed on a substrate with the printer unit.

The invention is not limited to the embodiments shown above, but can be varied within the scope of the appended claims.

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