Imaging device

Abstract

To provide a technique that can appropriately convert imaging data acquired by a camera into an image with a resolution necessary for an inspection.SOLUTION: An imaging apparatus 40 comprises a camera 41, an image data output unit 45, and an external output signal generation unit 47. The camera 41, based on camera output signals SC generated at a constant period, outputs imaging data D obtained by picking up an image printed on a print medium 9 conveyed in a conveyance direction X. The image data output unit 45 outputs image data DM based on the imaging data D to an inspection device 8. The external output signal generation unit 47 generates an external output signal SR indicating the timing at which the image data output unit 45 outputs the image data DM. The image data output unit 45 calculates a weighted average obtained by weighting the plurality of pieces of imaging data D accumulated in a buffer 51 with a weight according to the temporal displacement between the camera output signal SC and the external output signal SR.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The subject matter disclosed herein relates to imaging devices. [Background technology]

[0002] Conventionally, while transporting the printing medium in one direction, an image of the printed material is captured by a camera, and various inspections, such as print quality and nozzle checks, are performed based on the obtained image data. For example, Patent Document 1 describes obtaining a read image by reading a printed material on which a test pattern has been printed with a recording head using an inline sensor, and using the read image to obtain the recording characteristics of each nozzle in the recording head. [Prior art documents] [Patent Documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2021-187137 [Overview of the project] [Problems that the invention aims to solve]

[0004] When the imaging period of a camera, such as a line sensor, is kept constant, the resolution of the image data output by the camera depends on the transport speed of the printing medium. For example, if the transport speed decreases, the distance the printing medium moves during a single imaging cycle decreases, resulting in a higher resolution of the image data. Conversely, if the transport speed increases, the resolution of the image data decreases. Therefore, it may be necessary to convert the image data output by a line scan camera to match the resolution of the image used for inspection (hereinafter referred to as "inspection resolution").

[0005] The object of the present invention is to provide a technology that can appropriately convert imaging data acquired by a camera into an image with the resolution required for inspection. [Means for solving the problem]

[0006] To solve the above problems, the first embodiment is an imaging device comprising: a camera that outputs imaging data obtained by imaging an image printed on a printing medium transported in a first direction based on a camera output signal that occurs at a fixed period; an image data output unit that outputs image data based on the imaging data to an external device; and an external output signal generation unit that generates an external output signal indicating the timing at which the image data output unit outputs the image data, wherein the image data output unit includes a buffer capable of storing a plurality of imaging data output by the camera, and the plurality of imaging data stored in the buffer and the camera output signal The aforementioned External output signal and of The system includes an averaging processing unit that calculates a weighted average based on the time difference between intervals, and the image data output unit outputs the image represented by the weighted average calculated by the averaging processing unit as the image data. The imaging device further comprises a count signal generation unit that generates a count signal at a shorter period than the period of the camera output signal, the count signal generation unit generates the count signal by multiplying the camera output signal, and the image data output unit determines the weight based on the number of count signals generated during the time difference between the camera output signal and the external output signal. .

[0007] The second embodiment is an imaging apparatus according to the first embodiment, wherein the external output signal generation unit generates the external output signal based on the amount of the printing medium transported.

[0008] A third embodiment is an imaging apparatus according to the second embodiment, further comprising a transport amount detection unit for detecting the transport amount, wherein the external output signal generation unit generates the external output signal based on the transport amount detected by the transport amount detection unit.

[0009] A fourth embodiment is an imaging device according to the third embodiment, wherein the transport amount detection unit has a rotary encoder that outputs a pulse signal according to the amount of rotation of the transport roller that transports the printing medium, and the external output signal generation unit generates the external output signal based on the pulse signal.

[0010] A fifth embodiment is an imaging device according to the first or second embodiment, wherein the camera has a line sensor extending in a second direction intersecting the first direction. [Effects of the Invention]

[0012] From the first aspect to the 5According to the imaging device of the aspect, for the imaging data accumulated in the buffer, by taking a weighted average with a weight corresponding to the time shift between the camera output signal and the external output signal, the resolution of the imaging data output by the camera can be appropriately converted into image data with a desired resolution. Furthermore, according to the imaging apparatus of the first to fifth embodiments, the weight can be determined based on the number of count signals.

[0013] According to the imaging device of the second aspect, an external output signal can be generated based on the conveyance amount.

[0014] According to the imaging device of the third aspect, even if the resolution of the imaging data fluctuates due to a change in the conveyance speed of the print medium, the imaging data can be converted into image data with a required resolution.

[0015] According to the imaging device of the fifth aspect, an image on a print medium conveyed in one direction can be read by a line sensor.

Brief Description of the Drawings

[0017] [Figure 1] It is a diagram showing a printing device according to an embodiment. [Figure 2] It is a diagram showing the flow of processing executed when a camera and an image data output unit according to an embodiment receive a camera output signal. [Figure 3] It is a timing chart showing a first operation example of the imaging device according to an embodiment. [Figure 4] It is a time chart showing a second operation example of the imaging device according to an embodiment. [Figure 5] It is a time chart showing a third operation example of the imaging device according to an embodiment.

Mode for Carrying Out the Invention

[0018] Embodiments of the present invention will be described below with reference to the attached drawings. Note that the components described in these embodiments are merely illustrative and are not intended to limit the scope of the present invention to them alone. In the drawings, for ease of understanding, the dimensions and number of parts may be exaggerated or simplified as needed.

[0019] <1. First Embodiment> Figure 1 shows a printing apparatus 1 according to an embodiment. The printing apparatus 1 ejects ink droplets (hereinafter referred to as "ink droplets") onto a printing medium 9 using an inkjet method to form an image on the printing surface 91 of the printing medium 9. In this example, the printing medium 9 is a long strip (web-like). The printing medium 9 is, for example, printing paper, a resin film, or metal foil. As shown in Figure 1, the printing apparatus 1 comprises a transport unit 10, a printing unit 20, a printing control unit 30, and an imaging device 40.

[0020] The transport unit 10 continuously transports the printing medium 9 roll-to-roll from upstream to downstream along a predetermined transport path. Specifically, the transport unit 10 includes a feed roller 11, a plurality of transport rollers 12, and a winding roller 13. The feed roller 11, each transport roller 12, and the winding roller 13 are rotatable about an axis parallel to the width direction Y of the printing medium 9.

[0021] The feed roller 11 continuously feeds out the printing medium 9, which is wound in a roll on its outer circumference. Multiple transport rollers 12 are each positioned at predetermined locations along the transport path. Each transport roller 12 supports the printing medium 9 fed out from the feed roller 11 from the back side 92, opposite to the printing surface 91. The winding roller 13 winds up the printing medium 9 that has been stretched across each transport roller 12 into a roll and collects it.

[0022] The conveying unit 10 has a rotational drive unit, such as a motor, that rotates the winding roller 13. The conveying unit 10 may also include a rotational drive unit that rotates some or all of the unwinding roller 11 or a plurality of conveying rollers 12.

[0023] The transport unit 10 includes a transport amount detection unit 15. The transport amount detection unit 15 detects the amount (transport distance) of the printing medium 9 transported per certain period of time. Specifically, the transport amount detection unit 15 has a rotary encoder. The rotary encoder detects the amount of rotation (rotation angle) of the transport roller 12. The rotary encoder of the transport amount detection unit 15 outputs a pulse-shaped encoder signal SE each time the transport roller 12 rotates by a predetermined angle.

[0024] The method for detecting the amount of printing medium 9 transported is not limited to using a rotary encoder. For example, marks recorded on the printing medium 9 at predetermined intervals may be read by a camera or the like, and the amount of printing medium 9 transported per certain period of time may be calculated based on the time of reading.

[0025] The printing unit 20 prints an image onto the printing surface 91 of the printing medium 9, which is transported in one direction (transport direction X, indicated by the arrow in Figure 1) by the transport unit 10. The printing unit 20 has a plurality of print heads 21 that eject ink droplets. In this example, a print head 21 that ejects black (K) ink droplets, a print head 21 that ejects cyan (C) ink droplets, a print head 21 that ejects M (magenta) ink droplets, and a print head 21 that ejects yellow (Y) ink droplets are arranged in order toward the transport direction X, with spaces between them.

[0026] The color of the ink ejected by each print head 21 can be changed as desired. Furthermore, the printing unit 20 may have print heads 21 that eject ink droplets of colors different from K, C, M, and Y. Also, the number of print heads 21 in the printing unit 20 may be just one.

[0027] Multiple ejection nozzles (not shown) for ejecting ink droplets are arranged on the surface of the print head 21 facing the print surface 91 of the printing medium 9. The multiple ejection nozzles are arranged in the width direction Y, which is perpendicular to the transport direction X. The range in which the print head 21 can eject ink droplets (printable range) extends over the entire width direction Y of the printing medium 9. The printing apparatus 1 is a so-called single-pass (one-pass) printing apparatus that prints an image M1 on the printing medium 9 by ejecting ink droplets from each print head 21 while the printing medium 9 passes under the multiple print heads 21 only once.

[0028] The print control unit 30 controls the printing unit 20. The print control unit 30 is, for example, a computer equipped with a processor such as a CPU, memory such as RAM, and auxiliary storage devices such as a hard disk drive. The print control unit 30 may also be composed of dedicated electronic circuits such as application-specific semiconductor integrated circuits (ASICs).

[0029] The print control unit 30 controls the ejection of ink droplets from each nozzle of each print head 21 based on print data indicating the image to be printed on the print medium 9 and the amount of print medium 9 being transported (encoder signal SE output by the transport amount detection unit 15).

[0030] The imaging device 40 captures an image M1 printed on a printing medium 9 and outputs image data DM to an external inspection device 8. The inspection device 8 is a device that checks whether the image M1 is printed correctly by comparing the image data DM output from the imaging device 40 with a reference image. The inspection device 8 may also be a device that checks for density unevenness and color in the image M1. The imaging device 40 includes a camera 41, a camera output signal generation unit 43, an image data output unit 45, and an external output signal generation unit 47. The image data output unit 45 has a buffer 51, an averaging processing unit 53, and a rate setting unit 55.

[0031] Camera 41 is a line scan camera having a line sensor extending in the width direction Y. The line sensor consists of multiple image sensors arranged in a line in the width direction Y. The image sensors are CCD or CMOS. Camera 41 optically reads the colors of the image on the printing medium 9 using the line sensor and outputs imaging data D, which represents the image expressed in the RGB color space, to the buffer 51. The imaging data D is, for example, data showing the luminance values ​​of each RGB color for one line.

[0032] The camera output signal generation unit 43 generates a pulsed camera output signal SC with a constant period T1. As shown in Figure 1, the camera output signal SC is input to the camera 41, the count signal generation unit 44, and the rate setting unit 55 of the image data output unit 45, respectively.

[0033] The count signal generation unit 44 generates a count signal SCC. The count signal SCC is a pulsed signal generated by [unclear]. The period of the count signal SCC is preferably less than half the period T1 of the camera output signal SC.

[0034] In this example, the count signal generation unit 44 generates a count signal SCC based on the camera output signal SC. The count signal generation unit 44 generates the count signal SCC by multiplying the camera output signal SC (by 8 times in this example). The count signal SCC is input to the rate setting unit 55 of the image data output unit 45.

[0035] It is not mandatory that the count signal SCC be generated based on the camera output signal SC. In other words, the count signal SCC may be a signal generated independently of the camera output signal SC.

[0036] Camera 41 performs imaging based on the camera output signal SC and outputs the resulting imaging data D to buffer 51. Therefore, camera 41 performs imaging and output with a period T1. The exposure time when camera 41 performs imaging coincides with, for example, the period T1.

[0037] The image data output unit 45 outputs image data DM based on the imaging data D to the inspection device 8, which is an external device. As will be described later, the image data DM is data obtained by taking a weighted average of multiple imaging data D.

[0038] The external output signal generation unit 47 generates a pulsed external output signal SR that defines the timing at which the image data output unit 45 should output the image data DM. The external output signal generation unit 47 generates the external output signal SR based on the encoder signal SE output by the transport amount detection unit 15. The external output signal SR is input to the rate setting unit 55.

[0039] The external output signal SR is generated at a timing corresponding to the resolution required for inspection in the inspection device 8 (inspection resolution). More specifically, the external output signal SR is generated each time the printed medium 9 moves a distance equivalent to one pixel, as indicated by the inspection resolution. For example, if the inspection resolution is 600 dpi, the distance equivalent to one pixel is 42.3 μm (= 25.4 mm / 600). Therefore, the external output signal generation unit 47 generates the external output signal SR each time the printed medium 9 moves 42.3 μm. Alternatively, the encoder signal SE output by the transport amount detection unit 15 may be matched with the external output signal SR. In this case, the encoder signal SE can be used directly as the external output signal SR.

[0040] The image data output unit 45 includes a buffer 51, an averaging processing unit 53, and a rate setting unit 55. The buffer 51 is, for example, a semiconductor memory capable of temporarily storing multiple imaging data D output by the camera 41. The averaging processing unit 53 generates image data DM by weighting the multiple imaging data D stored in the buffer 51 with weights corresponding to the temporal difference between the camera output signal SC and the external output signal SR. The rate setting unit 55 determines the weights used by the averaging processing unit 53 when performing the weighted average.

[0041] The camera output signal generation unit 43, the count signal generation unit 44, the external output signal generation unit 47, the averaging processing unit 53, and the rate setting unit 55 are each composed of hardware consisting of logic circuits such as dedicated circuits. Alternatively, the functions of each of these units may be implemented in software by a general-purpose processor such as a CPU executing a program.

[0042] Figure 2 shows the flow of processing performed by the camera 41 and image data output unit 45 according to the embodiment when they receive the camera output signal SC. First, when the camera 41 receives the camera output signal SC, it starts imaging and outputs the obtained imaging data D to the buffer 51 (imaging / buffer output process S10). The rate setting unit 55 of the image data output unit 45 determines whether a new external output signal SR was received at the same time as the camera output signal SC was received, or whether a new external output signal SR was received before the time the camera output signal SC was received (determination process S11).

[0043] If the determination process S11 determines Yes, the rate setting unit 55 determines the weight for one or more image data D stored in the buffer 51 (weight determination process S12). The rate setting unit 55 determines the weight based on the time difference between the reception time of the camera output signal SC and the reception time of the external output signal SR. If there is no time difference between the reception time of the camera output signal SC and the reception time of the external output signal SR, the weight is determined to be 1.

[0044] After the weight determination process S12, the averaging processing unit 53 calculates a weighted average for each image data D (weighted averaging process S13). That is, the averaging processing unit 53 multiplies the weights set in the weight determination process S12 by the multiple image data D (specifically, the brightness values ​​of each RGB color), calculates the sum, and divides that sum by the sum of weights. In this way, the averaging processing unit 53 obtains image data DM, which is the weighted average of the multiple image data D.

[0045] The averaging processing unit 53 outputs the image data DM for one line obtained by the weighted averaging process S13 to the inspection device 8 (external output processing S14). Then, the image data output unit 45 terminates the processing.

[0046] <Example of operation 1> Figure 3 is a timing chart showing a first operational example of the imaging device 40 according to the embodiment. In the example in Figure 3, the external output signal SR is generated at the same timing as the encoder signal SE. The camera output signal SC is generated at times t1, t2, t3, t4, t5, and t6. The camera 41 is triggered by the camera output signal SC at times t1, t2, t3, t4, and t5 to output the imaging data D1, D2, D3, D4, and D5 obtained by imaging to the buffer 51 (imaging and buffer storage process S10 in Figure 2).

[0047] The image data output unit 45 receives the external output signal SR at the same time as the camera output signal SC at times t2 and t3. Therefore, the determination result of the determination process S11 in Figure 2 is Yes. There is no difference between the reception time of the camera output signal SC and the time of the external output signal SR. Accordingly, the weight is determined to be 1 by the weight determination process S12 in Figure 2 (weight determination process S12). Subsequently, the image data output unit 45 takes the imaging data D1 and D2 in the buffer 51 as image data DM corresponding to the external output signal SR at times t2 and t3, weights them by 1 (weighted averaging process S13 in Figure 2), and then outputs them to the outside (external output process S14 in Figure 2). The imaging data D1 and D2 output from the buffer 51 to the outside are deleted from the buffer 51 at an appropriate timing.

[0048] At time t4, the image data output unit 45 does not receive a new external output signal SR. That is, the image data output unit 45 has not received a new external output signal SR between time t3 and time t4, which initiated the output of the image data DM (image data D2) from the buffer 51 to the outside. Therefore, at time t4, the determination result of the determination process S11 in Figure 2 is No, and the weight determination process S12 to the external output process S14 in Figure 2 are not executed. Consequently, the imaging data D3 stored in the buffer 51 is not output to the outside.

[0049] The image data output unit 45 receives the camera output signal SC at time t5, prior to time t 11 A new external output signal SR has already been received at time t. Therefore, the image data output unit 45 has already received the new external output signal SR. 11 The weighted average of imaging data D3 and D4 is calculated as the image data DM corresponding to the external output signal SR.

[0050] The weights of the imaging data D3 and D4 are calculated from the reception time t3 of the aforementioned external output signal SR to the reception time t of the target external output signal SR. 11 Up to this point, the settings are determined according to the imaging time (exposure time) of each imaging data D3 and D4. In this example, the number of count signals SCC generated during each imaging time is used as the weight.

[0051] For example, the acquisition time of image data D3 is the time difference between time t3 and time t4, i.e., period T1. Period T1 corresponds to 8 count signals SCC. Therefore, the weight of image data D3 is set to "8". Also, the acquisition time of image data D4 is from time t4 to time t 11 The period until (time t4 and t 11 This corresponds to the time difference between the camera output signal SC and the external output signal SR, and here it corresponds to the three count signals SCC. For this reason, the weight of the imaging data D4 is set to "3". Therefore, at time t 11 The image data DM corresponding to the external output signal SR is expressed by the following equation.

[0052] DM = (D3 * 8 + D4 * 3) / 11

[0053] The image data output unit 45 receives the external output signal SR along with the camera output signal SC at time t6. The image data output unit 45 receives the image data D stored in the buffer 51 as image data DM corresponding to the external output signal SR at time t6. 4, Calculate the weighted average of D5. Here, the imaging time of the image data D4 to be output is time t. 11 Since it corresponds to ~t5, the weight is set to "5". Also, since the imaging time of imaging data D5 is equal to the period T1, the weight for imaging data D5 is "8". Therefore, the image data DM corresponding to the external output signal SR at time t6 is expressed by the following equation.

[0054] DM = (D4*5 + D5*8) / (5 + 8)

[0055] When the transport speed of the printing medium 9 decreases, the time interval of the external output signal SR increases, as shown in Figure 3. When the transport speed decreases, the resolution of the image data D acquired by the camera 41 becomes relatively higher. In contrast, in this embodiment, by weighting multiple image data D according to the time difference between the camera output signal SC and the external output signal SR, the resolution of the image data D can be reduced to match the inspection resolution. Therefore, the inspection device 8 can perform inspection appropriately. For example, when the inspection device 8 determines whether an image is properly printed by comparing the captured image D with a reference image, according to this embodiment, the captured image D and the reference image can always be compared at the same resolution regardless of the transport speed of the printing medium 9, making it possible to stably determine the suitability of the printed image. The same applies when the inspection device 8 determines density unevenness and color in the printed image.

[0056] In addition, in order to determine the weight based on the number of count signals SCC, the calculation process of the weighted average can be performed quickly. Also, by making the period of the count signal SCC smaller than 1 / 2 of the period T1 of the camera output signal SC (in this example, 1 / 8 of the period T1), a weight that accurately reflects the shift of the external output signal SR from the camera output signal SC can be determined. Thereby, the error between the actual printed image M1 and the weighted average image data DM can be reduced.

[0057] <Second operation example> FIG. 4 is a time chart showing a second operation example of the imaging device 40 according to the embodiment. Also in the example of FIG. 4, the external output signal SR is generated at the same timing as the encoder signal SE. Further, the camera output signal SC is generated at times t1, t2, t3, t4, t5, and t6. In the example of FIG. 4, the image data output unit 45 receives the external output signal SR at times t1 and t 12 and t6. Time t 12 is a time after time t4 and before time t5.

[0058] At times t2, t3, and t4, the image data output unit 45 does not receive a new external output signal SR. Therefore, at each of times t2, t3, and t4, the determination result of the determination process S11 in FIG. 2 is No, and the external output process S14 is not executed from the weight determination process S12 in FIG. 2. Therefore, the captured data D1, D2, and D3 stored in the buffer 51 are not output to the outside.

[0059] When the image data output unit 45 receives the camera output signal SC at time t5, it has already received a new external output signal SR at a time t 12 after time t4. Therefore, the image data output unit 45 calculates the weighted average of the plurality of captured data D1 to D4 stored in the buffer 51 from time t1 to t5 as the image data MD corresponding to the external output signal SR at time t 12 .

[0060] Specifically, the weights of imaging data D1, D2, and D3 are set to "8". The weight of imaging data D4 is set to the time of imaging data D4 (from time t4 to time t 12 Based on the period of time t, the weight becomes "5". That is, time t 12 The image data DM corresponding to the external output signal SR is expressed by the following equation.

[0061] DM = ((D1 + D2 + D3) * 8 + D4 * 5) / (24 + 5)

[0062] Furthermore, the image data output unit 45 receives the external output signal SR along with the camera output signal SC at time t6. Therefore, the image data output unit 45 receives the previous external output signal SR at time t 12 The weighted average of the imaging data D4 and D5 accumulated in buffer 51 at time t6 is calculated. Specifically, the weight of imaging data D4 is set to "3" and the weight of imaging data D5 is set to "8". Therefore, the image data DM for the external output signal SR at time t6 is expressed by the following equation.

[0063] DM = (D4*3 + D5*8) / (3 + 8)

[0064] <Third example of operation> Figure 5 is a time chart showing a third operation example of the imaging device 40 according to the embodiment. In the example in Figure 5, the external output signal SR is a signal generated with a constant period T2. That is, the external output signal SR is not a signal generated based on the encoder signal SE. Period T2 is greater than period T1. Also, in the example in Figure 5, the image data output unit 45 is at times t1, t 21 ,t 22 ,t 23 Each device receives the external output signal SR.

[0065] At time t2, the image data output unit 45 does not receive a new external output signal SR. Therefore, at time t2, the determination result of the determination process S11 in Figure 2 is No, and the weight determination process S12 to the external output process S14 in Figure 2 are not executed. As a result, the imaging data D1 stored in the buffer 51 is not output externally.

[0066] When the image data output unit 45 receives the camera output signal SC at time t3, it will output a time t that is later than time t2. 21 A new external output signal SR has already been received. Therefore, the image data output unit 45 calculates a weighted average of the imaging data D1 and D2 stored in the buffer 51.

[0067] The method for determining the weights is the same as the method explained in Figure 3. That is, from the reception time t2 of the previous external output signal SR to the reception time t of the target external output signal SR. 21 Of these, the imaging time of imaging data D1 (time t1~t2), and the imaging time of imaging data D2 (time t2~t 21 The weights are set according to the time t. In the example in Figure 5, the weight of imaging data D1 is set to "8" and the weight of imaging data D2 is set to "2". Therefore, the weights are set according to the time t. 21 The image data DM (weighted average) corresponding to the external output signal SR is expressed by the following formula.

[0068] DM = (D1 * 8 + D2 * 2) / (8 + 2)

[0069] Furthermore, when the image data output unit 45 receives the camera output signal SC at time t4, it will react to a time later than time t3. 22 A new external output signal SR has already been received. Therefore, the image data output unit 45 calculates the weighted average of the imaging data D2 and D3 stored in the buffer 51 at time t4. In the example in Figure 5, the weight of imaging data D2 is set to "6" and the weight of imaging data D3 is set to "4". Therefore, at time t 22 The image data DM (weighted average) corresponding to the external output signal SR is expressed by the following formula.

[0070] DM = (D2*6 + D3*4) / (6 + 4)

[0071] Furthermore, when the image data output unit 45 receives the camera output signal SC at time t5, it will react to a time t later than time t4. 23A new external output signal SR is received at time t. Therefore, the image data output unit 45 calculates a weighted average of the imaging data D3 and imaging data D4 stored in the buffer 51. In the example in Figure 5, the weight of imaging data D3 is set to "4" and the weight of imaging data D4 is set to "6". Therefore, at time t 23 The image data DM (weighted average) corresponding to the external output signal SR is expressed by the following formula.

[0072] DM = (D3*4 + D4*6) / (4 + 6)

[0073] As described above, even in the absence of an encoder signal SE, the imaging data D can be appropriately converted into image data DM, which is the inspection resolution, by generating an external output signal SR at a frequency corresponding to the inspection resolution.

[0074] <2. Variant Example> Although embodiments have been described above, the present invention is not limited to those described above, and various modifications are possible.

[0075] For example, in the above embodiment, the number of count signals SCC corresponding to the imaging time of the imaging data D is used as the weight for the imaging data D, but the actual imaging time may be calculated and the calculated imaging time may be used as the weight. For example, in the example of Figure 3, time t 11 When calculating the image data DM corresponding to the external output signal SR, the weight of the imaging data D3 is set to the period T1 (=t4-t3), and the weight of the imaging data D4 is set to the time t4~t 11 The period (t 11 -t4) is also acceptable.

[0076] Although this invention has been described in detail, the above description is illustrative in all respects, and the invention is not limited thereto. It is understood that countless variations not illustrated can be conceived without falling outside the scope of this invention. The components described in each of the above embodiments and variations can be combined or omitted as appropriate, as long as they do not contradict each other. [Explanation of symbols]

[0077] 9 Print media 15. Transport volume detection unit 40 Imaging device 41 Cameras 43 Camera output signal generation unit 44 Count signal generation unit 45 Image data output unit 47 External output signal generation unit 51 buffers 53 Averaging Processing Unit D Imaging data DM image data SC camera output signal SCC count signal SE encoder signal SR external output signal

Claims

1. An imaging device, A camera that outputs imaging data obtained by capturing an image printed on a printing medium being transported in a first direction, based on a camera output signal that occurs at regular intervals, An image data output unit that outputs image data based on the aforementioned imaging data to an external device, An external output signal generation unit generates an external output signal that indicates the timing at which the image data output unit outputs the image data, Equipped with, The aforementioned image data output unit is A buffer capable of storing multiple image data output by the aforementioned camera, An averaging processing unit calculates a weighted average of the plurality of imaging data stored in the buffer, with weights corresponding to the time difference between the camera output signal and the external output signal. It has, The image data output unit outputs the image shown by the weighted average calculated by the averaging processing unit as the image data. The imaging device is A count signal generation unit that generates a count signal with a period shorter than the period of the camera output signal, Furthermore, The count signal generation unit multiplies the camera output signal to obtain the count signal Generate a number, The image data output unit determines the weight based on the number of count signals generated during the time difference between the camera output signal and the external output signal.

2. The imaging apparatus according to claim 1, The external output signal generation unit generates the external output signal based on the amount of the printing medium transported, and is an imaging device.

3. The imaging apparatus according to claim 2, A transport amount detection unit that detects the transport amount, Furthermore, The external output signal generation unit generates the external output signal based on the transport amount detected by the transport amount detection unit in the imaging device.

4. The imaging apparatus according to claim 3, The transport amount detection unit has a rotary encoder that outputs a pulse signal according to the amount of rotation of the transport roller that transports the printing medium. The external output signal generation unit is an imaging device that generates the external output signal based on the pulse signal.

5. An imaging apparatus according to claim 1 or claim 2, The camera is an imaging device having a line sensor extending in a second direction intersecting the first direction.

Images