Colorimeter, colorimeter method, and program

Abstract

This invention provides a colorimeter, a colorimeter, and a program that can measure colors with high accuracy even when the colorimeter chart is tilted. [Solution] The colorimeter of the present invention comprises a colorimeter head for measuring the color of a colorimeter chart printed on a recording medium, a moving means for moving the colorimeter head back and forth in the CD direction, a transport means for transporting the recording medium in the FD direction perpendicular to the CD direction, and a control unit for controlling the operation of the moving means and the transport means. The colorimeter chart has a plurality of colorimeter patches and a plurality of position patches arranged in the CD direction and the FD direction. The colorimeter head comprises a colorimeter sensor for measuring the color of the colorimeter patches and a position sensor for reading position information of the position patches. The control unit controls the starting position for colorimetering in the FD direction based on information from a plurality of position patches located apart in the FD direction.

Description

Technical Field

[0001] The present invention relates to a color measuring device, a color measuring method, and a program.

Background Art

[0002] A color measuring device that automatically measures and corrects the position of a color measuring chart is known (see, for example, Patent Document 1).

Prior Art Document

Patent Document

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the color measuring device disclosed in Patent Document 1, the accuracy of position measurement is low, and the accuracy of automatic color measurement when the color measuring chart has an inclination is not sufficient.

[0005] The present invention has been made in view of the above situation. The problem to be solved by the present invention is to provide a color measuring device, a color measuring method, and a program that can perform color measurement with high accuracy even when the color measuring chart has an inclination.

Means for Solving the Problems

[0006] The above problems according to the present invention are solved by the following means.

[0007] 1. A color measuring head that measures a color measuring chart printed on a recording medium, Moving means for reciprocating the color measuring head in the CD direction, Transport means for transporting the recording medium in the FD direction orthogonal to the CD direction, A control unit that controls the operations of the moving means and the transport means, and The colorimetric chart has a plurality of colorimetric patches arranged in the CD direction and the FD direction, and a plurality of position patches, The colorimetric head comprises a colorimetric sensor for measuring the color of the colorimetric patch and a position sensor for reading the position information of the position patch. The control unit controls the color measurement start position in the FD direction based on information from a plurality of position patches that are separated in the FD direction. Colorimetric device.

[0008] 2. The position patch has an FD position patch whose primary purpose is to indicate position information in the FD direction, The longitudinal edge of the FD position patch is used to acquire position information in the CD direction. The colorimeter described in paragraph 1.

[0009] 3. The control unit calculates the tilt amount of the colorimetric chart from the vertical edge information of the FD position patch in the (n-2)th row and the vertical edge information of the FD position patch in the nth row, and controls the starting position for color measurement when measuring the colorimetric patch in the nth row based on the tilt amount. The colorimeter described in paragraph 2.

[0010] 4. The control unit calculates the inclination amount from the transport amount of the recording medium in the FD direction and the difference between the vertical edge positions of the FD position patches in the nth row and the (n-2nd)th row. The colorimeter described in paragraph 3.

[0011] 5. The position patch is located upstream of the FD position patch and has a CD position patch whose longitudinal edge position in the CD direction is the same as that of the FD position patch. The colorimeter described in paragraph 2.

[0012] 6. The position patch is located away from the colorimetric patch, is black, and is rectangular. The colorimeter described in paragraph 1.

[0013] 7. The measurement diameter of the position sensor is smaller than the measurement diameter of the colorimetric sensor. The colorimetric device according to claim 1.

[0014] 8. The control unit calculates the inclination amount of the colorimetric chart from the information of the plurality of position patches arranged in the FD direction only on one side, either the left or the right, of the colorimetric patch, and controls the colorimetric start position in the FD direction based on the inclination amount. The colorimetric device according to claim 1.

[0015] 9. The control unit controls the colorimetric start position in the FD direction based only on the inclination amount calculated first. The colorimetric device according to claim 8.

[0016] 10. The colorimetric start position in the FD direction is set to three patterns: the upper position, the center position, and the lower position of the colorimetric patch. When the recording medium is conveyed, the control unit aligns the upper position of the colorimetric patch and the position of the colorimetric sensor in the FD direction and stops the recording medium. The colorimetric device according to claim 2. The colorimetric device according to claim 2.

[0017] 11. A colorimetric method using a colorimetric device including: a colorimetric head for colorimetrically measuring a colorimetric chart printed on a recording medium; moving means for reciprocally moving the colorimetric head in the CD direction; and conveying means for conveying the recording medium in the FD direction orthogonal to the CD direction. The colorimetric chart has a plurality of colorimetric patches and a plurality of position patches arranged in the CD direction and the FD direction. The colorimetric head includes a colorimetric sensor for colorimetrically measuring the colorimetric patch and a position sensor for reading the position information of the position patch. The colorimetric start position in the FD direction is controlled based on the information of the plurality of position patches separated in the FD direction. Moving means for reciprocally moving the colorimetric head in the CD direction; A colorimetric method using a colorimetric device comprising: conveying means for conveying the recording medium in the FD direction orthogonal to the CD direction, The colorimetric chart has a plurality of colorimetric patches and a plurality of position patches arranged in the CD direction and the FD direction, The colorimetric head includes a colorimetric sensor for colorimetrically measuring the colorimetric patch and a position sensor for reading the position information of the position patch, Controlling the colorimetric start position in the FD direction based on the information of the plurality of position patches separated in the FD direction. Colorimetric method.

[0018] 12. A program for causing the computer in a colorimetric apparatus, which comprises a colorimetric head for measuring the color of a colorimetric chart printed on a recording medium, a moving means for moving the colorimetric head back and forth in the CD direction, a transport means for transporting the recording medium in the FD direction perpendicular to the CD direction, and a computer, to function as a control unit for controlling the operation of the moving means and the transport means, The colorimetric chart has a plurality of colorimetric patches arranged in the CD direction and the FD direction, and a plurality of position patches, The colorimetric head comprises a colorimetric sensor for measuring the color of the colorimetric patch and a position sensor for reading the position information of the position patch. The control unit controls the color measurement start position in the FD direction based on information from a plurality of position patches that are separated in the FD direction. program. [Effects of the Invention]

[0019] According to the present invention, a colorimeter, a colorimeter, and a program can be provided that can measure color with high accuracy even when the colorimeter chart is tilted. [Brief explanation of the drawing]

[0020] [Figure 1] This is a schematic diagram of one embodiment of a printing apparatus. [Figure 2] This is a block diagram showing the functional configuration of one embodiment of a printing device. [Figure 3] This is a schematic diagram of one embodiment of a colorimeter. [Figure 4] This figure shows an example of a colorimetric chart. [Figure 5] This is a flowchart illustrating an example of the colorimetric process. [Figure 6] This figure shows an example of the operation of the colorimeter head. [Figure 7] This diagram explains how to calculate the amount of slope. [Figure 8] This figure shows the case where the starting position for color measurement in the FD direction is located at the top of the color measurement patch. [Figure 9]This figure shows the case where the starting position for color measurement in the FD direction is the center position of the color measurement patch. [Figure 10] This figure shows the case where the starting position for color measurement in the FD direction is at the lower end of the color measurement patch. [Modes for carrying out the invention]

[0021] The following description illustrates one or more embodiments of the present invention with reference to the drawings. The effects and features of the embodiments of the present invention will be understood from the following detailed description and drawings. The following detailed description and drawings are provided for illustrative purposes only and do not limit the scope of the present invention.

[0022] [Printing device] Figure 1 is a schematic diagram of one embodiment of a printing apparatus 100 equipped with the colorimeter 1 of the present invention. Figure 2 is a block diagram showing the functional configuration of one embodiment of the printing apparatus 100 equipped with the colorimeter 1 of the present invention. Figures 1 and 2 show the printing apparatus 100 as an example when the printing method is an inkjet method. However, the printing method is not limited to the inkjet method and may be, for example, an electrophotographic method. The printing apparatus 100 when the printing method is an inkjet method will be described below using Figures 1 and 2.

[0023] As shown in Figures 1 and 2, the printing apparatus 100 may include a colorimeter 1, a paper feeding unit 2, a transport unit 3, a printing unit 4, an image scanning unit 5, a paper discharge unit 6, a DFE 7 (digital front end), a main unit control unit 8, and a main unit operation unit 9.

[0024] The paper feeding unit 2 stores the recording medium M. The paper feeding unit 2 has, for example, a tray. Examples of recording medium M include paper, fabric, sheet-like resin, etc. Examples of paper include plain paper, coated paper, etc. The recording medium M is preferably a sheet of paper.

[0025] As shown in Figure 1, the transport unit 3 includes, for example, a feeder board 31, a first transfer drum 32, a transport drum 33, a second transfer drum 34, and an unloading unit 35.

[0026] The feeder board 31 transports the recording medium M from the paper feeding unit 2 to the first transfer drum 32. The first transfer drum 32 holds one end of the recording medium M transported by the feeder board 31, picks it up, and transfers it to the transport drum 33.

[0027] The transport drum 33 is, for example, cylindrical. The side surface of the transport drum 33 serves as a transport surface that attracts and holds the recording medium M. With the recording medium M held on the transport surface, the transport drum 33 rotates in one direction around its central axis as the axis of rotation. As a result, the transport drum 33 transports the recording medium M, which is attracted and held on the transport surface, along the transport surface.

[0028] The printing unit 4 may have, for example, one or more head units 41. The printing unit 4 performs a printing process to produce a printed material P using an inkjet method. Each head unit 41 has one or more inkjet heads. The head unit 41 may have an ink ejection surface at a position facing the transport surface of the transport drum 33. The head unit 41 ejects ink onto the recording medium M held in the transport drum 33 at an appropriate timing corresponding to the rotation of the transport drum 33 to form an image and produce a printed material P. In the printing apparatus 100 illustrated in Figure 1, four head units 41 are arranged at predetermined intervals in order from the upstream side in the rotational direction of the transport drum 33. The four head units 41 correspond to, for example, four colors of ink: yellow, magenta, cyan, and black.

[0029] The printing unit 4 may have an ultraviolet irradiation unit 42 downstream of the head unit 41 in the transport direction. If the ink is an ultraviolet-curable ink, the ultraviolet irradiation unit 42 can cure the ink on the recording medium M by irradiating it with ultraviolet light.

[0030] In the printing section 4, normal jobs, color measurement jobs, etc., are performed. A normal job is a printing job that produces a regular printed material P that is not subject to color measurement. A color measurement job is a printing job that produces a printed material P that is subject to color measurement. The image formed in the color measurement job may be a color measurement chart 200, or it may be the same image as the image formed in the normal job.

[0031] The image scanning unit 5 irradiates light onto the printed material P from a light source and reads the reflected image. The image scanning unit 5 is composed of, for example, an inline sensor in which multiple detection elements are arranged along a direction (width direction) perpendicular to the transport direction of the recording medium M. The image data read by the image scanning unit 5 is sent to, for example, the DFE 7, the main unit control unit 8, etc.

[0032] The second transfer drum 34 holds one end of the printed material P transported by the transport drum 33, picks it up, and hands it over to the discharge unit 35.

[0033] The discharge section 35 is the discharge path for the printed material P, and it transports the printed material P to the paper discharge section 6 or the colorimeter 1. The discharge section 35 is composed of, for example, a belt, rollers, etc. The transport path in the discharge section 35 may branch along the way, as shown in Figure 1. The printed material P is discharged to the paper discharge section 6. The paper discharge section 6 has, for example, a tray.

[0034] The DFE (Digital Front End) 7 comprises a RIP (Raster Image Processor) 71, a color correction unit 72, a colorimetric chart generation unit 73, an ICC profile generation unit 74, and a job generation unit 75. The main control unit 8 comprises a job control unit 81, a transport control unit 82, and a colorimetric data processing unit 83. The main operation unit 9 comprises a colorimetric job instruction unit 91.

[0035] [Color measurement device] As shown in Figures 2 and 3, the colorimeter 1 may include a colorimeter head 11, a moving means 12, a transport means 13, a control unit 14, and a colorimeter data transfer unit 15. The colorimeter head 11 measures the color of a colorimeter chart 200 printed on a recording medium M. The moving means 12 moves the colorimeter head 11 back and forth in the CD direction (Cross Direction). The transport means 13 transports the recording medium M in the FD direction (Feed Direction), which is perpendicular to the CD direction. The control unit 14 controls the operation of the moving means 12 and the transport means 13. The colorimeter data transfer unit 15 transfers the colorimeter data to, for example, a DFE 7. As shown in Figure 1, the colorimeter 1 may be provided inline with the printing device 100.

[0036] As shown in Figure 3, the colorimetric head 11 includes a colorimetric sensor 11a for measuring the color of the colorimetric patch 201 and a position sensor 11b for reading the position information of the position patch. Colorimetric measurement is the measurement of color information, for example, L * a * b * This involves measuring color values ​​such as values. As the colorimeter 11a, for example, a spectrophotometer that spectrally measures the reflected light from the colorimeter patch 201 can be used. The position sensor 11b is, for example, mechanically mounted adjacent to the colorimeter sensor 11a and is movable in the CD direction together with the colorimeter sensor 11a when the colorimeter head 11 moves.

[0037] The measuring diameter of the position sensor 11b is preferably smaller than the measuring diameter of the colorimeter sensor 11a. This improves the accuracy of position measurement. The measuring diameter of the position sensor 11b is, for example, less than 1 mm. The measuring diameter of the colorimeter sensor 11a is, for example, about 3 to 4 mm.

[0038] The colorimetric chart 200 has multiple colorimetric patches 201 and multiple position patches 202A-D, 203A-J. When the colorimetric patches 201 are not tilted, they are aligned in the CD direction and the FD direction. The size of the colorimetric chart 200 is not particularly limited, and is, for example, B2 size (515mm x 728mm). If the colorimetric chart 200 is large, even a slight tilt of the colorimetric chart 200 can easily cause the reading position of the colorimetric sensor 11a to shift relative to the colorimetric patches 201. However, because the colorimetric device 1 of the present invention has high position measurement accuracy, it can measure color with high accuracy even when the colorimetric chart 200 is large.

[0039] An example of a colorimetric chart 200 will be explained using Figure 4. The following explanation describes the colorimetric chart 200 illustrated in Figure 4 and does not limit the colorimetric chart 200 according to the present invention.

[0040] In the colorimetric chart 200 illustrated in Figure 4, the multiple colorimetric patches 201 constitute multiple columns arranged in the CD direction and multiple rows arranged in the FD direction. Specifically, the multiple colorimetric patches 201 are arranged from column 1 C1 to column 12 C 12 And, row 1 R1 to row 10 R 10 It is composed of the following.

[0041] As shown in Figure 4, it is preferable that position patches 202A-D and 203A-J are positioned away from the colorimetric patch 201. This makes it easier for the position sensor 11b to acquire position information of the edges of position patches 202A-D and 203A-J. It is preferable that position patches 202A-D and 203A-J are black. This increases the contrast with the recording medium M when the recording medium M is white, improving the accuracy of position measurement. It is preferable that position patches 202A-D and 203A-J are rectangular.

[0042] The multiple position patches include CD position patches 202A to D, whose primary purpose is to indicate position information in the CD direction, and FD position patches 203A to J, whose primary purpose is to indicate position information in the FD direction.

[0043] Multiple FD position patches 203A to J are positioned on either the left or right side of the colorimetric patch 201, or both sides, spaced apart from each other in the FD direction. Each FD position patch 203A to J is positioned such that its position in the FD direction coincides with each row of the colorimetric patch 201. Specifically, FD position patches 203A, C, E, G, and I, which are aligned in the FD direction on the left side of the colorimetric patch 201, are positioned such that their positions in the FD direction coincide with each odd-numbered row of the colorimetric patch 201. FD position patches 203B, D, F, H, and J, which are aligned in the FD direction on the right side of the colorimetric patch 201, are positioned such that their positions in the FD direction coincide with each even-numbered row of the colorimetric patch 201. In this invention, "left side" refers to the left side in the direction of transport of the recording medium M. "Right side" refers to the right side in the direction of transport of the recording medium M.

[0044] Multiple CD position patches 202A to D are located upstream of the colorimetric patch 201, spaced apart from each other in the CD direction. Upstream refers to the upstream side in the transport direction of the recording medium M.

[0045] CD position patch 202A has the same vertical edge position in the CD direction as FD position patches 203A, C, E, G, and I, which are located to the left of colorimetric patch 201. CD position patch 202D has the same vertical edge position in the CD direction as FD position patches 203B, D, F, H, and J, which are located to the right of colorimetric patch 201. The vertical edge position refers to the position of the edge of the position patch along the FD direction. CD position patches 202A and D are used, for example, to control the colorimetric start position 204 of colorimetric patch 201 in the first row R1.

[0046] CD position patches 202B and C align with the CD direction of the columns at both ends of colorimetric patch 201. Specifically, CD position patch 202B aligns with the CD direction of the first column C1 of colorimetric patch 201. CD position patch 202C aligns with the CD direction of the twelfth column C of colorimetric patch 201. 12 The CD direction matches.

[0047] In addition to controlling the operation of the moving means 12 and the transport means 13, the control unit 14 can also control the operation of the colorimetric head 11, the colorimetric data transfer unit 15, and other components. The control unit 14 is a computer and includes, for example, a CPU (Central Processing Unit). The CPU executes various control programs to perform drive control of the measuring device, various calculation processing, etc.

[0048] Hereinafter, an example of the color measurement process when performing color measurement using the color measurement chart 200 illustrated in Figure 4 in a printing apparatus 100 equipped with the color measurement device 1 of the present invention will be explained using Figures 5 to 10. As shown in Figure 6, in the following explanation, the home position of the color measurement head 11 will be referred to as position a. Position a is located to the left of the color measurement chart 200. Position b is the position where the positions of the left FD position patches 203A, C, E, G, and I coincide with the CD direction. Position c is the position where the positions of the right FD position patches 203B, D, F, H, and J coincide with the CD direction.

[0049] In step S1, the printing unit 4 prints a colorimetric chart 200 onto the recording medium M. The flow then proceeds to step S2, in which position patches are read from the colorimetric chart 200 as follows.

[0050] First, with the colorimetric head 11 in position a, the control unit 14 transports the recording medium M to align the position of the colorimetric head 11 with the position of the CD position patch in the FD direction. This can be done by pre-defining the printing position of the CD position patch from the leading edge of the recording medium M in the transport direction.

[0051] Next, the control unit 14 moves the colorimetric head 11 from position a, through position b, to position c. At this time, the position sensor 11b reads the position information of each left edge of CD position patches 202A to D. The left edge refers to the left vertical edge of the position patch. From the position information of each left edge of CD position patches 202B and C obtained here, the control unit 14 calculates the amount of movement of the colorimetric head 11 required for each colorimetric patch 201. After that, the control unit 14 returns the colorimetric head 11 to its home position at position a.

[0052] Next, the control unit 14 moves the colorimetric head 11 to position b based on the position information of the left edge of the CD position patch 202A. Then, the control unit 14 transports the recording medium M. At this time, the control unit 14 stops the recording medium M by aligning the position of the colorimetric sensor 11a in the FD direction with the upper alignment position of the colorimetric patch 201 located in the frontmost column (in this case, the 1st column) of the row to be measured next. The frontmost column can be rephrased as the column closest to the colorimetric head 11. The upper alignment position is a position closer to the upstream side in the transport direction within the range that overlaps with the colorimetric patch 201 in the FD direction. During the transport of this recording medium M, the position where the output of the position sensor 11b changes from black to white and then from white to black is detected as the leading edge of the FD position patch 203A. The leading edge is the upstream edge of the position patch.

[0053] Subsequently, the control unit 14 returns the colorimetric head 11 to its home position at position a. At this time, the position sensor 11b acquires the position information of the left edge (left vertical edge) of the FD position patch 203A.

[0054] Next, the flow proceeds to step S3, in which the slope amount is calculated as follows. First, the control unit 14 obtains the difference Δx in the CD direction of the vertical edge positions of the CD position patch 202A and the FD position patch 203A from the position information of the left edge of these position patches. Furthermore, as shown in Figure 7, the control unit 14 calculates the slope amount of the colorimetric chart from the obtained difference Δx of the vertical edge positions in the CD direction and the transport amount Δy of the recording medium M in the FD direction. This slope amount becomes "information of multiple position patches separated in the FD direction". Note that in Figure 7, the slope of the colorimetric chart 200 is shown to be larger than the slope actually expected for illustrative purposes.

[0055] In this control system, the position information of the left edge of CD position patch 202A and the position information of the left edge of FD position patch 203A are information from multiple position patches separated in the FD direction. Based on this information, the starting position 204 for color measurement in the FD direction is controlled. In addition, the left edge (left vertical edge) of FD position patch 203A is used to acquire position information in the CD direction.

[0056] Next, the flow proceeds to step S4. In step S4, the control unit 14 determines the color measurement start position 204 in the FD direction based on the amount of inclination calculated in step S3. In this control example, the color measurement start position 204 in the FD direction is controlled in three patterns: an upper position, a central position, and a lower position of the color measurement patch 201. In odd-numbered steps S4, including the first time, the control is as follows: As shown in Figure 8, if the color measurement chart 200 is tilted counterclockwise with respect to the CD direction, or if the amount of counterclockwise inclination is greater than a predetermined threshold, the color measurement start position 204 in the FD direction is controlled to the upper position of the color measurement patch 201. As described above, the upper position is a position closer to the upstream side in the transport direction within the range that overlaps with the color measurement patch 201 in the FD direction. As shown in Figure 9, if the color measurement chart 200 is not tilted with respect to the CD direction, or if the amount of inclination is less than a predetermined threshold, the color measurement start position 204 in the FD direction is controlled to the central position of the color measurement patch 201. The central position refers to the center position in the transport direction within the range that overlaps with the colorimetric patch 201 in the FD direction. As shown in Figure 10, if the colorimetric chart 200 is tilted clockwise with respect to the CD direction, or if the amount of clockwise tilt is greater than a predetermined threshold, the colorimetric start position 204 in the FD direction is controlled to a lower position of the colorimetric patch 201. The lower position refers to a position closer to the downstream side in the transport direction within the range that overlaps with the colorimetric patch 201 in the FD direction.

[0057] Next, the process proceeds to step S5. In step S5, it is determined whether the color measurement start position 204 in the FD direction is in an upward position.

[0058] If it is determined in step S5 that the starting position 204 for color measurement in the FD direction is not in an upward position, the flow proceeds to step S6. In step S6, it is determined whether or not the starting position 204 for color measurement in the FD direction is in the center position.

[0059] If in step S6 it is determined that the starting position 204 for color measurement in the FD direction is not in the center position, that is, if it is determined that the starting position 204 for color measurement in the FD direction is in a lower position, the flow proceeds to step S7. In step S7, additional recording media M are transported so that the position of the color measurement sensor 11a in the FD direction temporarily coincides with the center position of the color measurement patch 201 in the first row and first column.

[0060] If it is determined in step S6 that the starting position 204 for color measurement in the FD direction is the center position, or after step S7, the flow proceeds to step S8. If the process proceeds from step S6 to step S8 without going through step S7, in step S8, additional recording media M are transported so that the position of the color measurement sensor 11a in the FD direction coincides with the center position of the first row and first column color measurement patch 201. If the process proceeds after step S7 to step S8, in step S8, additional recording media M are transported so that the position of the color measurement sensor 11a in the FD direction coincides with the lower position of the first row and first column color measurement patch 201.

[0061] The additional transport of the recording medium M in steps S7 and S8 can be rephrased as correction of the transport amount of the recording medium M, or correction of the position of the recording medium M.

[0062] If it is determined in step S5 that the starting position 204 for color measurement in the FD direction is an upward position, or after step S8, the flow proceeds to step S9. In step S9, the control unit 14 moves the color measurement head 11 in the CD direction and causes the color measurement sensor 11a to read the color measurement patch 201, thereby performing the first row of color measurement. The dashed arrows pointing to the right in Figures 6 and 8-9 indicate the movement path of the color measurement head 11 during the measurement of the first row.

[0063] Next, the flow proceeds to step S10. In step S10, it is determined whether or not the color measurement of all colorimetric patches 201 has been completed.

[0064] If it is determined in step S10 that the color measurement of all color measurement patches 201 has not been completed, the flow returns to step S2. In the second step S2, as in the first step S2, the control unit 14 first transports the recording medium M. At this time, the control unit 14 aligns the position of the color measurement sensor 11a with the position of the color measurement patch 201 located in the frontmost column of the row to be measured next (in this case, the 12th column) in the FD direction, and stops the recording medium M. After that, the control unit 14 moves the color measurement head 11 in the CD direction and causes the position sensor 11b to acquire the position information of the left edge of the FD position patch 203B.

[0065] Next, the flow proceeds to step S3 again. In the second step S3, the control unit 14 first calculates the difference Δx in the CD direction of the vertical edge positions of the CD position patch 202D and the FD position patch 203B from the position information of the left edge of the CD position patch 202D and the position information of the left edge of the FD position patch 203B. Furthermore, the control unit 14 calculates the tilt amount of the colorimetric chart from the calculated difference Δx of the vertical edge positions and the transport amount Δy of the recording medium M in the FD direction.

[0066] In this control, the position information of the left edge of CD position patch 202D and the position information of the left edge of FD position patch 203B are information of multiple position patches that are separated in the FD direction. Based on this information, the color measurement start position 204 in the FD direction is controlled.

[0067] Next, the flow proceeds to step S4. In step S4, the control unit 14 determines the color measurement start position 204 in the FD direction based on the amount of tilt calculated in step S3. In even-numbered steps S4, including the second time, the control is as follows: As shown in Figure 8, if the colorimetric chart 200 is tilted counterclockwise with respect to the CD direction, or if the amount of counterclockwise tilt is greater than a predetermined threshold, the color measurement start position 204 in the FD direction is controlled to a lower position of the color measurement patch 201. As shown in Figure 9, if the colorimetric chart 200 is not tilted with respect to the CD direction, or if the amount of tilt is less than a predetermined threshold, the color measurement start position 204 in the FD direction is controlled to a central position of the color measurement patch 201. As shown in Figure 10, if the colorimetric chart 200 is tilted clockwise with respect to the CD direction, or if the amount of clockwise tilt is greater than a predetermined threshold, the color measurement start position 204 in the FD direction is controlled to an upper position of the color measurement patch 201.

[0068] Subsequently, the flow proceeds to step S5, just as in the first time, and thereafter repeats the same process as described above. In this way, all colorimetric patches 201 are measured while the amount of inclination and the starting position of colorimetric measurement 204 are controlled for each row. Note that the dashed arrows pointing to the left in Figures 6 and 8-9 indicate the movement path of the colorimetric head 11 during the measurement of the second row.

[0069] If it is determined in step S10 that the color measurement of all colorimetric patches 201 has been completed, the flow proceeds to step S11. In step S11, the colorimetric data is transferred to the DFE7 by the colorimetric data transfer unit 15 and stored.

[0070] After step S11, the colorimetric process ends. After the colorimetric process ends, a normal job is performed, for example, and the colorimetric process may be performed again as needed after or during the normal job.

[0071] In this control example, from the third row onward, the control unit 14 calculates the tilt amount of the colorimetric chart 200 from the position information of the left edge of the FD position patch in row n-2 (left vertical edge information) and the position information of the left edge of the FD position patch in row n (left vertical edge information). The control unit 14 also controls the starting position 204 for color measurement when measuring the colorimetric patch 201 in row n based on this tilt amount.

[0072] As described above, in the colorimeter 1 of the present invention, the control unit 14 controls the color measurement start position 204 in the FD direction based on information from multiple position patches that are separated in the FD direction. This makes it less likely for the reading position of the colorimeter sensor 11a to shift relative to the colorimeter patch 201, even if the colorimeter chart 200 is tilted, thus reducing errors in the measured color value. This improves the accuracy of color measurement. Furthermore, in the colorimeter 1 of the present invention, since the reading position of the colorimeter sensor 11a is less likely to shift relative to the colorimeter patch 201, it becomes possible to reduce the size of the colorimeter patch 201. Therefore, it becomes possible to increase the number of colorimeter patches 201 printed per recording medium M.

[0073] In another embodiment, the tilt amount of the colorimetric chart 200 may be calculated from the information of multiple position patches arranged in the FD direction on only one side of the colorimetric patch 201 (either left or right), and the starting position 204 for colorimetric measurement in the FD direction may be controlled based on this tilt amount. The one side of the colorimetric patch 201 is, for example, the left side of the colorimetric patch 201. Alternatively, the starting position 204 for colorimetric measurement in the FD direction for each row may be controlled based only on the tilt amount calculated initially. By reducing the number of times the tilt amount is calculated in this way, colorimetric measurement becomes more efficient, for example, when there is no difference in the tilt amount in each row.

[0074] The correction of the transport amount of the recording medium M may be performed at intervals of any number of lines, such as every line or every few lines.

[0075] [Color measurement method] The colorimetric method of the present invention is a colorimetric method using the colorimetric device 1 described above, and controls the colorimetric start position 204 in the FD direction based on information from a plurality of position patches that are separated in the FD direction.

[0076] [program] The program of the present invention is a program that causes the computer provided in the above-described colorimeter 1 to function as a control unit 14 that controls the operation of the moving means 12 and the transport means 13. The computer that functions as the control unit 14 by this program controls the colorimeter 1 as described above.

[0077] The above description and drawings are for illustrative purposes only and do not intend to limit the scope of the present invention. The scope of the present invention should be interpreted as stated in the claims. [Explanation of symbols]

[0078] 100 Printing device 1 Colorimetric device 11 Colorimeter head 11a Colorimetric sensor 11b Position sensor 12 Means of Transportation 13 Conveying means 14 Control Unit 15. Colorimetric data transfer unit 2 Paper feed section 3. Conveying section 31 Feeder board 32. First handover drum 33 Conveyor Drum 34. Second handover drum 35. Loading section 4 Printing Department 41 Head Unit 42 UV irradiation area 5. Image scanning unit 6. Paper output section 7 DFE 71 RIP 72 Color Correction Section 73 Colorimetric chart generation unit 74 ICC Profile Generation Unit 75 Job Generation Unit 8 Main Unit Control 81 Job Control Unit 82 Transport Control Unit 83 Colorimetric Data Processing Unit 9. Main Unit Control Panel 91 Color Measurement Job Instruction Unit 200 Colorimetric Chart 201 Colorimetric Patch 202A~D CD position patch 203A~J FD position patch 204 Color measurement start position M recording medium P Printed matter

Claims

1. A colorimeter head for measuring the color of a colorimeter chart printed on a recording medium, A moving means for moving the colorimeter head back and forth in the direction of the CD, A transport means for transporting the recording medium in the FD direction perpendicular to the CD direction, The system comprises a control unit that controls the operation of the moving means and the transport means, The colorimetric chart has a plurality of colorimetric patches arranged in the CD direction and the FD direction, and a plurality of position patches, The colorimetric head comprises a colorimetric sensor for measuring the color of the colorimetric patch and a position sensor for reading the position information of the position patch. The control unit controls the color measurement start position in the FD direction based on information from a plurality of position patches located apart in the FD direction. Colorimetric device.

2. The aforementioned position patch has an FD position patch whose primary purpose is to indicate position information in the FD direction, The vertical edge of the FD position patch is used to acquire position information in the CD direction. The colorimeter according to claim 1.

3. The control unit calculates the tilt amount of the colorimetric chart from the vertical edge information of the FD position patch in the (n-2)th row and the vertical edge information of the FD position patch in the nth row, and controls the starting position for color measurement when measuring the colorimetric patch in the nth row based on the tilt amount. The colorimeter according to claim 2.

4. The control unit calculates the inclination amount from the transport amount of the recording medium in the FD direction and the difference between the vertical edge positions of the FD position patches in the nth row and the (n-2nd)th row. The colorimeter according to claim 3.

5. The aforementioned position patch is located upstream of the aforementioned FD position patch and has a CD position patch whose longitudinal edge position in the CD direction is the same as that of the aforementioned FD position patch. The colorimeter according to claim 2.

6. The position patch is located away from the colorimetric patch, is black, and is rectangular. The colorimeter according to claim 1.

7. The measuring diameter of the position sensor is smaller than the measuring diameter of the colorimeter. The colorimeter according to claim 1.

8. The control unit calculates the tilt amount of the colorimetric chart from the information of the multiple position patches arranged in the FD direction, only on either the left or right side of the colorimetric patch, and controls the colorimetric start position in the FD direction based on the tilt amount. The colorimeter according to claim 1.

9. The control unit controls the color measurement start position in the FD direction based solely on the tilt amount calculated initially. The colorimeter according to claim 8.

10. The starting position for color measurement in the FD direction is set to one of three patterns: an upper position, a central position, and a lower position of the color measurement patch. The control unit, when transporting the recording medium, aligns the upper position of the colorimetric patch with the position of the colorimetric sensor in the FD direction and stops the recording medium. The colorimeter according to claim 2.

11. A colorimeter head for measuring the color of a colorimeter chart printed on a recording medium, A moving means for moving the colorimeter head back and forth in the direction of the CD, A colorimetric method using a colorimetric apparatus comprising a transport means for transporting the recording medium in a FD direction perpendicular to the CD direction, The colorimetric chart has a plurality of colorimetric patches arranged in the CD direction and the FD direction, and a plurality of position patches, The colorimetric head comprises a colorimetric sensor for measuring the color of the colorimetric patch and a position sensor for reading the position information of the position patch. Based on the information of the multiple position patches separated in the FD direction, the color measurement start position in the FD direction is controlled. Color measurement method.

12. A program for causing the computer in a colorimetric apparatus, which comprises a colorimetric head for measuring the color of a colorimetric chart printed on a recording medium, a moving means for moving the colorimetric head back and forth in the CD direction, a transport means for transporting the recording medium in the FD direction perpendicular to the CD direction, and a computer, to function as a control unit for controlling the operation of the moving means and the transport means, The colorimetric chart has a plurality of colorimetric patches arranged in the CD direction and the FD direction, and a plurality of position patches, The colorimetric head comprises a colorimetric sensor for measuring the color of the colorimetric patch and a position sensor for reading the position information of the position patch. The control unit controls the color measurement start position in the FD direction based on information from a plurality of position patches located apart in the FD direction. program.

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