Camera device

Abstract

According to an embodiment of the present invention, an imaging device includes: a pixel array, which includes charges divided into multiple pixel rows and accumulates charges corresponding to the amount of received light during an accumulation period; an exposure control unit, which sets the duration of the accumulation period to one of multiple durations in a predetermined order of repetition; and a processing unit, wherein: the accumulation period includes a first accumulation period and a second accumulation period having a first duration, and a third accumulation period and a fourth accumulation period having a second duration; and the processing unit generates image data by adding multiple pixel values ​​based on the accumulation result of the first pixel row during the first accumulation period with multiple pixel values ​​based on the accumulation result of the second pixel row during the second accumulation period, and adding multiple pixel values ​​based on the accumulation result of the first pixel row during the third accumulation period with multiple pixel values ​​based on the accumulation result of the second pixel row during the fourth accumulation period.

Description

Technical Field

[0001] The present invention relates to an imaging device for imaging a subject. Background Art

[0002] The imaging device includes, for example, a line sensor including one or more pixel rows. For example, Patent Document 1 discloses a line sensor including two or more pixel rows, wherein the pixel rows have different sensitivities.

[0003] Citation list

[0004] Patent Literature

[0005] Patent Document 1: Japanese Unexamined Patent Application Publication No. H09-162381 Summary of the invention

[0006] In line sensors, high image quality is desired, and further improvement of the image quality is desired.

[0007] It is desirable to provide an image pickup apparatus capable of improving image quality.

[0008] An image pickup device according to an embodiment of the present invention includes: a pixel array, an exposure controller, and a processor. The pixel array includes a plurality of light receiving pixels. The plurality of light receiving pixels are divided into a plurality of pixel rows, and accumulate charges corresponding to the amount of light received during an accumulation period. The plurality of pixel rows include: a first pixel row and a second pixel row arranged in parallel along a first direction. The exposure controller sets the time length of the accumulation period of the plurality of light receiving pixels to one of a plurality of time lengths including a first time length and a second time length, so that the plurality of time lengths are repeated in a predetermined order. The processor generates image data based on the accumulation results of the plurality of light receiving pixels. The accumulation period includes a first accumulation period and a second accumulation period each having the first time length, and a third accumulation period and a fourth accumulation period each having the second time length. The processor generates the image data by adding a plurality of pixel values ​​based on the accumulation result of the first pixel row during the first accumulation period to a plurality of pixel values ​​based on the accumulation result of the second pixel row during the second accumulation period, and adding a plurality of pixel values ​​based on the accumulation result of the first pixel row during the third accumulation period to a plurality of pixel values ​​based on the accumulation result of the second pixel row during the fourth accumulation period.

[0009] In an image pickup device according to an embodiment of the present invention, the time length of the accumulation period of the plurality of light receiving pixels is set to one of the plurality of time lengths including the first time length and the second time, so that the plurality of time lengths are repeated in a predetermined order. In the light receiving pixels, the charge corresponding to the light reception amount is accumulated during the accumulation period. The plurality of light receiving pixels are divided into the plurality of pixel rows, which include the first pixel row and the second pixel row arranged in parallel in the first direction. In the processor, the image data is generated by adding a plurality of pixel values ​​based on the accumulation result of the first pixel row during the first accumulation period having the first time length and a plurality of pixel values ​​based on the accumulation result of the second pixel row during the second accumulation period having the second time length, and adding a plurality of pixel values ​​based on the accumulation result of the first pixel row during the third accumulation period and a plurality of pixel values ​​based on the accumulation result of the second pixel row during the fourth accumulation period. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 : is an explanatory diagram showing a configuration example of an inspection system including an imaging device according to an embodiment of the present invention.

[0011] Figure 2 It shows Figure 1 A block diagram of a configuration example of an imaging device shown in FIG.

[0012] Figure 3 It shows that Figure 2 An explanatory diagram of an example of TDI processing performed in the imaging device shown.

[0013] Figure 4A It shows that Figure 2 FIG. 2 is another explanatory diagram of an example of the TDI process performed in the imaging device shown in FIG.

[0014] Figure 4B It shows that Figure 2 FIG. 2 is another explanatory diagram of an example of the TDI process performed in the imaging device shown in FIG.

[0015] Figure 5 It shows Figure 2 A timing chart showing an example of the operation of the imaging device shown.

[0016] Fig. 6A It shows that Figure 2 FIG. 2 is another explanatory diagram of an example of the TDI process performed in the imaging device shown in FIG.

[0017] Figure 6B It shows that Figure 2FIG. 2 is another explanatory diagram of an example of the TDI process performed in the imaging device shown in FIG.

[0018] Figure 7 It is shown by Figure 2 An explanatory diagram of an example of an image generated by the imaging device shown.

[0019] Figure 8 2 is an explanatory diagram showing an example of TDI processing to be performed in the image pickup apparatus according to the first comparative example.

[0020] Fig. 9 : is a timing chart showing an operation example of the image pickup device according to the first comparative example.

[0021] Fig.10 : is an explanatory diagram showing an example of an image generated by the imaging device according to the first comparative example.

[0022] Fig.11 : is a timing chart showing an operation example of the image pickup device according to the second comparative example.

[0023] Fig.12 is a timing chart showing an operation example of the image pickup device according to the modification.

[0024] Fig.13 : is an explanatory diagram showing an example of TDI processing to be performed in an image pickup apparatus according to a modification.

[0025] Fig.14 is a timing chart showing an operation example of an image pickup device according to another modification.

[0026] Fig.15 is a timing chart showing an operation example of an image pickup device according to another modification.

[0027] Fig.16 is a block diagram showing a configuration example of an image pickup device according to another modification.

[0028] Fig.17 is a block diagram showing a configuration example of an image pickup device according to another modification. DETAILED DESCRIPTION

[0029] Hereinafter, some embodiments of the present invention are described in detail with reference to the accompanying drawings.

[0030] <Implementation Plan>

[0031] [Configuration example]

[0032] Figure 1The configuration example of an inspection system 90 including an imaging device (imaging device 1) according to the embodiment is shown. For example, the inspection system 90 is configured to image an industrial product transported by a belt conveyor and inspect the industrial product using the acquired image. The inspection system 90 includes a belt conveyor 91, a conveying controller 92, a lens system 93, an imaging device 1, an HDR (High Dynamic Range) processor 94, and an inspection processor 95.

[0033] The belt conveyor 91 is configured to convey the industrial product to be inspected along a conveying direction F. The industrial product is a subject 9 to be photographed by the imaging device 1 .

[0034] The conveying controller 92 is configured to control the conveying operation to be performed by the belt conveyor 91. In addition, the conveying controller 92 generates a synchronization signal SYNC corresponding to the conveying speed of the belt conveyor 91. The synchronization signal SYNC includes a plurality of pulses provided at intervals corresponding to the conveying speed. In this example, as described later, the interval of the pulses is set to a time that is the same as the time for the image of the object 9 to advance one pixel row L on the imaging plane S of the imaging device 1. Then, the conveying controller 92 supplies the synchronization signal SYNC to the imaging device 1.

[0035] The lens system 93 is configured to guide an image of the subject 9 to an imaging plane S of the imaging device 1. In this example, the lens system 93 is a Keplerian-type system.

[0036] The imaging device 1 is a linear sensor and is configured to capture an image of a subject 9 conveyed by a belt conveyor 91 through a lens system 93. In this example, the lens system 93 is a Kepler type system. Therefore, the subject 9 moves in a direction opposite to the conveying direction F on an imaging plane S of the imaging device 1. The imaging device 1 performs an imaging operation according to each of a plurality of pulses included in a synchronization signal SYNC. As will be described later, the imaging device 1 includes eight pixel rows L in this example. Based on the synchronization signal SYNC, the imaging device 1 performs an imaging operation each time the image of the subject 9 advances one pixel row L on the imaging plane S. The imaging device 1 is adapted to provide image data DT representing the imaging result to the HDR processor 94.

[0037] The HDR processor 94 is configured to generate image data including an image with a wider dynamic range by performing HDR processing based on the image data DT supplied from the image pickup device 1. Then, the HDR processor 94 supplies the inspection processor 95 with the generated image data.

[0038] The inspection processor 95 is configured to inspect the industrial product (the object 9 ) based on the image data supplied from the HDR processor 94 .

[0039] Figure 2 1 shows a configuration example of an image pickup device 1. The image pickup device 1 includes a pixel array 11, an exposure controller 12, a pixel controller 13, a memory 14, a TDI (Time Delay Integration) processor 15, a TDI memory 16, and an output processor 17.

[0040] The pixel array 11 includes a plurality of light receiving pixels PIX arranged in a matrix form. The light receiving pixels PIX include photodiodes. In this example, the plurality of light receiving pixels PIX are divided into eight pixel rows L. Figure 2 , 8 pixel rows L are arranged in parallel in the vertical direction. The direction of parallel arrangement (vertical direction) is the direction in which the image of the subject 9 moves. Each of the eight pixel rows L includes a predetermined number of light receiving pixels PIX. Each of the plurality of light receiving pixels PIX is configured to perform an accumulation operation of accumulating charges corresponding to the amount of light reception during an accumulation period P, and to perform an AD (analog to digital) conversion operation of converting an analog signal corresponding to the charges accumulated during the accumulation period P into a pixel value as a digital value. Based on an instruction from the pixel controller 13, the accumulation operation and the AD conversion operation in the plurality of light receiving pixels PIX are performed.

[0041] The exposure controller 12 is configured based on the transmission controller 92 ( Figure 1 ) controls the accumulation operation and AD conversion operation to be performed in the pixel array 11 using the synchronization signal SYNC supplied thereto. Specifically, the exposure controller 12 sets an accumulation period P (accumulation period PL) having a long time length TL and an accumulation period P (accumulation period PS) having a short time length TS in a time-division and alternating manner based on the synchronization signal SYNC. Then, the exposure controller 12 generates an exposure start signal SST indicating the start time of the accumulation period P and an exposure end signal SED indicating the end time of the accumulation period P, generates a conversion start signal SAD indicating the start time of the AD conversion operation, and supplies these signals to the pixel controller 13. In addition, the exposure control section 12 generates an exposure type signal EX indicating which of the processing corresponding to the accumulation result of the accumulation period PL or the processing corresponding to the accumulation result of the accumulation period PS will be performed, and supplies the exposure type signal EX to the TDI processor 15.

[0042] The pixel controller 13 is configured to control the accumulation operation by driving the plurality of light receiving pixels PIX included in the pixel array 11 based on the exposure start signal SST and the exposure end signal SED supplied from the exposure controller 12, and to control the AD conversion operation by driving the plurality of light receiving pixels PIX included in the pixel array 11 based on the conversion start signal SAD supplied from the exposure controller 12. In addition, the pixel controller 13 also has a function of controlling the operation of transferring the respective pixel values ​​generated by the plurality of light receiving pixels PIX to the memory 14 after the AD conversion operation is completed.

[0043] The memory 14 is provided near the pixel array 11 and is configured to temporarily store a plurality of pixel values ​​supplied from the plurality of light receiving pixels PIX included in the pixel array 11. The memory 14 is a logical memory storing the same number of pixel values ​​as the number of the plurality of light receiving pixels PIX included in the pixel array 11.

[0044] The TDI processor 15 is configured to read a plurality of pixel values ​​stored in the memory 14 in units of a plurality of pixel values ​​associated with one pixel row L, and perform TDI processing based on the plurality of pixel values ​​that have been read. Specifically, the TDI processor 15 performs TDI processing 100L using pixel values ​​based on the accumulation result of the accumulation period PL and performs TDI processing 100S using pixel values ​​based on the accumulation result of the accumulation period PS.

[0045] The TDI memory 16 is a memory used by the TDI processor 15 in performing the TDI process. The TDI memory 16 includes a TDI memory 16L and a TDI memory 16S. The TDI memory 16L and the TDI memory 16S are logic memories and are each capable of storing data, the number of which is the same as the number of light receiving pixels PIX in the pixel array 11. The TDI memory 16L stores data generated when the TDI processor 15 performs the TDI process 100L, and the TDI memory 16S stores data generated when the TDI processor 15 performs the TDI process 100S.

[0046] The output processor 17 is configured to generate image data DT by reading data from the TDI memory 16L and the TDI memory 16S based on an instruction from the TDI processor 15 .

[0047] With this configuration, the exposure controller 12 sets the accumulation period PL having a long time length TL and the accumulation period PS having a short time length TS in a time-division and alternating manner. Then, in each accumulation period P, a plurality of light receiving pixels PIX perform an accumulation operation and then perform an AD conversion operation, thereby generating a pixel value. The TDI processor 15 performs TDI processing 100L using a pixel value based on the accumulation result of the accumulation period PL, and performs TDI processing 100S using a pixel value based on the accumulation result of the accumulation period PS. Therefore, the imaging device 1 can widen the dynamic range.

[0048] The pixel array 11 corresponds to a specific example of a “pixel array” according to the present invention. The light receiving pixel PIX corresponds to a specific example of a “light receiving pixel” according to the present invention. The pixel row L corresponds to a specific example of a “pixel row” according to the present invention. The exposure controller 12 corresponds to a specific example of an “exposure controller” according to the present invention. The TDI processor 15, the TDI memory 16, and the output processor 17 correspond to a specific example of a “processor” according to the present invention. The TDI memory 16S corresponds to a specific example of a “first storage unit” according to the present invention. The TDI memory 16L corresponds to a specific example of a “second storage unit” according to the present invention. The accumulation period P corresponds to a specific example of an “accumulation period” according to the present invention. The time length TS corresponds to a specific example of a “first time length” according to the present invention. The time length TL corresponds to a specific example of a “second time length” according to the present invention. The synchronization signal SYNC corresponds to a specific example of a “synchronization signal” according to the present invention.

[0049] [Operation and function]

[0050] Next, the operation and effect of the image pickup device 1 according to the present embodiment will be described.

[0051] (Overview of overall operation)

[0052] First, refer to Figure 2, an overview of the overall operation of the image pickup device 1 will be described. The exposure controller 12 sets an accumulation period PL having a long time length TL and an accumulation period PS having a short time length TS in a time-division manner based on the synchronization signal SYNC. Then, the exposure controller 12 generates an exposure start signal SST, an exposure end signal SED, a conversion start signal SAD, and an exposure type signal EX. The pixel controller 13 controls the accumulation operation of the plurality of light receiving pixels PIX included in the pixel array 11 based on the exposure start signal SST and the exposure end signal SED, and controls the AD conversion operation of the light receiving pixels PIX included in the pixel array 11 based on the conversion start signal SAD. Each of the plurality of light receiving pixels PIX included in the pixel array 11 performs an accumulation operation of accumulating charges corresponding to the light reception amount during the accumulation period P, and performs an AD conversion operation of converting an analog signal corresponding to the accumulated charges into a pixel value as a digital value. The memory 14 temporarily stores a plurality of pixel values ​​supplied from the plurality of light receiving pixels PIX included in the pixel array 11. The TDI processor 15 reads a plurality of pixel values ​​stored in the memory 14 in units of a plurality of pixel values ​​associated with one pixel row L, and performs TDI processing 100L using pixel values ​​based on the accumulation result of the accumulation period PL, and performs TDI processing 100S using pixel values ​​based on the accumulation result of the accumulation period PS. The TDI memory 16L stores data generated when the TDI processor 15 performs the TDI processing 100L, and the TDI memory 16S stores data generated when the TDI processor 15 performs the TDI processing 100S. The output processor 17 generates image data DT by reading data from the TDI memory 16L and the TDI memory 16S according to an instruction from the TDI processor 15.

[0053] (Detailed operation)

[0054] Figure 3 , Figure 4A and Figure 4B Each shows an example of TDI processing to be performed in the TDI processor 15 . Figure 3 An example of TDI processing of a line image associated with 1 pixel line L is shown, Figure 4A An example of TDI processing 100S based on the accumulation result of the accumulation time PS is shown, and Figure 4B An example of a TDI process 100L based on the accumulation result of the accumulation time PL is shown.

[0055] The exposure controller 12 sets the accumulation period P every time the image of the subject 9 advances one pixel row L on the imaging plane S based on the synchronization signal SYNC. Figure 3As shown in FIG. 1 , the pixel array 11 generates images P1 to P8 based on the accumulation results of each of the eight accumulation periods P set sequentially. In the images P1 to P8, the subject 9 is displayed in units of one pixel row L as time passes. Figure 3 For example, the row image associated with pixel row L1 of image P1, the row image associated with pixel row L2 of image P2, the row image associated with pixel row L3 of image P3, the row image associated with pixel row L4 of image P4, the row image associated with pixel row L5 of image P5, the row image associated with pixel row L6 of image P6, the row image associated with pixel row L7 of image P7, and the row image associated with pixel row L8 of image P8 each represent the same portion of subject 9.

[0056] The exposure controller 12 sets the accumulation period PL having a long time length TL and the accumulation period PS having a short time length TS in a time-division and alternating manner. Figure 3 In the figure, images P1, P3, P5 and P7 respectively surrounded by solid lines are images generated based on the accumulation results of the accumulation period PS with a short time length TS, and images P2, P4, P6 and P8 respectively surrounded by dotted lines are images generated based on the accumulation results of the exposure time PL with a long time length TL.

[0057] The TDI processor 15 performs the TDI processing 100S using the pixel value of the accumulation result based on the accumulation period PS. In this example, the TDI processor 15 performs the TDI processing 100S by adding the row image related to the most upstream pixel row L1 in the image P1, the row image related to the third pixel row L3 in the image P3, the row image related to the fifth pixel row L5 in the image P5, and the row image related to the seventh pixel row L7 in the image P7 in units of pixels. This enables the imaging device 1 to obtain a row image with high sensitivity related to the accumulation period PS with a short time length TS.

[0058] In a similar manner, the TDI processor 15 performs the TDI processing 100L using the pixel value based on the accumulation result of the accumulation period PL. In this example, the TDI processor 15 performs the TDI processing 100L by adding the row image associated with the second pixel row L2 in the image P2, the row image associated with the fourth pixel row L4 in the image P4, the row image associated with the sixth pixel row L6 in the image P6, and the row image associated with the most downstream pixel row L8 in the image P8 in units of pixels. This enables the imaging device 1 to obtain a row image with high sensitivity associated with the accumulation period PL having a long time length TL.

[0059] In the above description, attention is paid to one pixel row L in each of the images P1 to P8; however, the situation is similar for the other pixel rows L.

[0060] For example, Figure 4A As shown, the TDI processor 15 performs TDI processing 100S based on the image P1, the image P3, the image P5, the image P7, the image P9, the image P11, and the image P13 related to the accumulation period PS having a short time length TS. Specifically, the TDI processor 15 performs TDI processing 100S based on the row image related to the first pixel row L1 in the image P1, the row image related to the third pixel row L3 in the image P3, the row image related to the fifth pixel row L5 in the image P5, and the row image related to the seventh pixel row L7 in the image P7. Then, the TDI processor 15 performs TDI processing 100S based on the row image related to the second pixel row L2 in the image P1, the row image related to the fourth pixel row L4 in the image P3, the row image related to the sixth pixel row L6 in the image P5, and the row image related to the eighth pixel row L8 in the image P7. In this way, the TDI processor 15 generates two rows of row images based on the image P1, the image P3, the image P5, and the image P7. In a similar manner, the TDI processor 15 generates two lines of line images based on the images P3, P5, P7, and P9, generates two lines of line images based on the images P5, P7, P9, and P11, and generates two lines of line images based on the images P7, P9, P11, and P13. In this way, the imaging device 1 can obtain an image DS having high sensitivity in relation to the accumulation period PS having a short time length TS.

[0061] In a similar manner, for example, Figure 4BAs shown, the TDI processor 15 performs TDI processing 100L based on the image P2, the image P4, the image P6, the image P8, the image P10, the image P12, and the image P14 related to the accumulation period PL having the long time length TL. Specifically, the TDI processor 15 performs TDI processing 100L based on the line image related to the first pixel row L1 in the image P2, the line image related to the third pixel row L3 in the image P4, the line image related to the fifth pixel row L5 in the image P6, and the line image related to the seventh pixel row L7 in the image P8. Then, the TDI processor 15 performs TDI processing 100L based on the line image related to the second pixel row L2 in the image P2, the line image related to the fourth pixel row L4 in the image P4, the line image related to the sixth pixel row L6 in the image P6, and the line image related to the eighth pixel row L8 in the image P8. In this way, the TDI processor 15 generates two lines of line images based on the image P2, the image P4, the image P6, and the image P8. In a similar manner, the TDI processor 15 generates two lines of line images based on the images P4, P6, P8, and P10, generates two lines of line images based on the images P6, P8, P10, and P12, and generates two lines of line images based on the images P8, P10, P12, and P14. In this way, the imaging device 1 can obtain an image DL with high sensitivity associated with the accumulation period PL having a long time length TL.

[0062] If the accumulation period P is an accumulation period PS having a short time length TS, the pixel array 11 can capture, for example, a bright portion of the subject 9 with high image quality. Furthermore, if the accumulation period P is an accumulation period PL having a long time length TL, the pixel array 11 can capture, for example, a dark portion of the subject 9 with high image quality. Therefore, the imaging device 1 can achieve a wide dynamic range.

[0063] The camera 1 outputs the image DS associated with the accumulation period PS and the image DS associated with the accumulation period PL, which have been generated by such TDI processing, as image data DT. Then, the HDR processor 94 combines the image DS associated with the accumulation period PS and the image DL associated with the accumulation period PL by HDR processing. In other words, in the image DS associated with the accumulation period PS having a short time length TS, for example, information of the dark part of the subject 9 is lacking, and in the image DL associated with the accumulation period PL having a long time length TL, for example, information of the bright part of the subject 9 is lacking. The HDR processor 94 is capable of combining the image DS and the image DL by, for example, making the two images DS and DL compensate for the missing information from each other, and selecting an image portion with a satisfactory S / N ratio from the two images DS and DL. This enables the HDR processor 94 to generate an image with a wide dynamic range. Then, the inspection processor 95 inspects the industrial product (subject 9) based on the image with a wide dynamic range combined by the HDR processor 94. Therefore, the inspection system 90 is capable of improving the accuracy of industrial product inspection.

[0064] Next, more detailed operations of the image pickup device 1 will be described.

[0065] Figure 5 An operation example of the camera device 1 is shown, wherein (A) shows a waveform of the synchronization signal SYNC, (B) shows a waveform of the exposure start signal SST, (C) shows a waveform of the exposure end signal SED, (D) shows a waveform of the exposure type signal EX, (E) shows an accumulation operation performed in the pixel array 11, and (F) shows processing performed in the TDI processor 15.

[0066] Conveyor controller 92( Figure 1 ) controls the conveying operation of the belt conveyor 91 and generates a synchronization signal SYNC ( Figure 5 (A)). In this way, the interval (synchronization interval Tf) of a plurality of pulses of the synchronization signal SYNC is set to the same time as the time for the image of the object 9 to advance one pixel row L on the imaging plane S of the imaging device 1. The conveying controller 92 maintains the conveying speed of the belt conveyor 91 at a constant speed, and generates pulses at a constant interval (synchronization interval Tf) in the synchronization signal SYNC.

[0067] In this example, if Figure 5As shown in (A), the transport controller 92 generates a pulse of the synchronization signal SYNC at time t1, generates the next pulse of the synchronization signal SYNC at time t11 after the synchronization interval Tf(1) has passed from time t1, and generates the next pulse of the synchronization signal SYNC at time t21 after the synchronization interval Tf(2) has passed from time t11.

[0068] The exposure controller 12 generates an exposure start signal SST, an exposure end signal SED, and an exposure type signal EX based on the time at which the delay time Td has passed from the rising edge of the synchronization signal SYNC as a reference time. The delay time Td includes a processing delay time required for implementation. The delay time Td can be intentionally set to a predetermined time. Specifically, for example, the delay time Td can be set in such a way that the rising edge of the synchronization signal SYNC coincides with the center time of the accumulation period P.

[0069] First, the exposure controller 12 sets the time t12 after the delay time Td from the time t11 as the rising edge of the synchronization signal SYNC as the reference time, and generates a pulse of the exposure start signal SST at the time t13 after the time Tls(1) from the reference time. Figure 5 (B)), and a pulse of the exposure end signal SED is generated at time t14 after time tle(1) from the reference time. In this way, the accumulation period PL having a long time length TL is set in the period from time t13 to time t14 ( Figure 5 (E)). In the pixel array 11, the accumulation period PL is set at the same time in all pixel rows L from the most upstream pixel row L1 to the most downstream pixel row L8. Each light receiving pixel PIX performs an accumulation operation of accumulating charges corresponding to the light receiving amount during the accumulation period PL, and performs an AD conversion operation of converting an analog signal corresponding to the accumulated charges into a pixel value as a digital value during a predetermined period after the end of the accumulation period PL. The memory 14 stores a plurality of pixel values ​​related to the accumulation period PL obtained in the plurality of light receiving pixels PIX.

[0070] The exposure controller 12 generates an exposure type signal EX ( Figure 5 In this example, the exposure controller 12 changes the exposure type signal EX from a low level to a high level based on the rising edge of the exposure end signal SED at time t14. Based on the exposure type signal EX, the TDI processor 15 performs the following operations during the period from time t14 to time t24 ( Figure 5 (F)) performs TDI processing 100L using a plurality of pixel values ​​associated with the accumulation period PL stored in the memory 14.

[0071] Fig. 6A An example of TDI processing 100L is shown. The TDI processor 15 sequentially reads a row of multiple pixel values ​​corresponding to one pixel row L in the memory 14 in units of rows. In addition, the TDI processor 15 reads a row of multiple values ​​in the TDI memory 16L corresponding to the data of one row read from the memory 14. The data of the row read from the memory 14 and the data of the row read from the TDI memory 16L are both data representing the same part of the subject 9. The TDI processor 15 generates multiple values ​​by adding the multiple pixel values ​​of the row read from the memory 14 and the multiple values ​​of the row read from the TDI memory 16L in units of pixels. Then, the TDI processor 15 writes the generated multiple values ​​into the read row in the TDI memory 16L. The TDI processor 15 thus updates eight rows of data in the TDI memory 16L.

[0072] In this example, the TDI processor 15 processes one row of data of the TDI memory 16L by reading a plurality of pixel values ​​of each row from the memory 14; however, this example is not limited thereto. Alternatively, for example, the TDI processor 15 may process two rows of data of the TDI memory 16L by reading a plurality of pixel values ​​of every two rows from the memory 14.

[0073] When such TDI processing 100L is completed, the eight lines of data in the TDI memory 16L include two lines of data added four times, two lines of data added three times, two lines of data added twice, and two lines of data added once. The output processor 17 reads the two lines of data added four times among the eight lines of data, and outputs the read data as image data DT. In other words, Figure 3 and Figure 4A As shown, four lines of images are added to complete the TDI processing 100L related to the line image, and therefore, the output processor 17 outputs two lines of data added four times as image data DT. Then, the TDI processor 15 resets the two lines of data of the TDI memory 16L read by the output processor 17. It should be noted that in this example, the two lines of data have been reset; however, the example is not limited to this. Or, for example, as an alternative to resetting, next, when the two lines of data in the TDI memory 16L are updated, they may not be added to the data read from the memory 14 and may be written to the TDI memory 16L as is.

[0074] In a similar way, Figure 5 As shown, the exposure control unit 12 sets the time t22 after the delay time Td from the time t21 as the rising edge of the synchronization signal SYNC as the reference time, and generates a pulse of the exposure start signal SST at the time t23 after the time Tss(2) from the reference time. Figure 5(B)), and a pulse of the exposure end signal SED is generated at time t24 after a time tse(2) from the reference time ( Figure 5 In this way, the accumulation period PS having a short time length TS is set in the period from time t23 to time t24 ( Figure 5 (E)). In the pixel array 11, the accumulation period PS of all pixel rows L from the most upstream pixel row L1 to the most downstream pixel row L8 is set at the same time. Each light receiving pixel PIX performs an accumulation operation of accumulating charges corresponding to the light receiving amount during the accumulation period PS, and performs an AD conversion operation of converting an analog signal corresponding to the accumulated charges into a pixel value as a digital value during a predetermined period after the end of the accumulation period PS. The memory 14 stores a plurality of pixel values ​​related to the accumulation period PS obtained in the plurality of light receiving pixels PIX.

[0075] The exposure controller 12 changes the exposure type signal EX from high level to low level based on the rising edge of the exposure end signal SED at time t24. Based on the exposure type signal EX, the TDI processor 15 performs the period from time t24 to time t34 ( Figure 5 (F)) performs TDI processing 100S using a plurality of pixel values ​​associated with the accumulation period PS stored in the memory 14.

[0076] Figure 6B An example of TDI processing 100S is shown. The TDI processor 15 sequentially reads a plurality of pixel values ​​of a row corresponding to one pixel row L in the memory 14 in row units. In addition, the TDI processor 15 reads a plurality of values ​​of a row of the TDI memory 16S corresponding to the data of a row read from the memory 14. The row of data read from the memory 14 and the row of data read from the TDI memory 16S are both data representing the same portion of the subject 9. The TDI processor 15 generates a plurality of values ​​by adding the plurality of pixel values ​​of the row read from the memory 14 and the plurality of values ​​of the row read from the TDI memory 16S in pixel units. Then, the TDI processor 15 writes the generated plurality of values ​​into the read row of the TDI memory 16S. The TDI processor 15 thus updates eight rows of data in the TDI memory 16S.

[0077] When such TDI processing 100S is completed, the eight lines of data of the TDI memory 16S include: two lines of data added four times, two lines of data added three times, two lines of data added twice, and two lines of data added once. The output processor 17 reads the two lines of data added four times among the eight lines of data, and outputs the read data as image data DT. Then, the TDI processor 15 resets the two lines of data of the TDI memory 16S read by the output processor 17.

[0078] In this way, the camera device 1 sets the accumulation period PL with a long time length TL and the accumulation period PS with a short time length TS in a time-division and alternating manner, and performs TDI processing 100L using the pixel value based on the accumulation result of the accumulation period PL, and performs TDI processing 100S using the pixel value based on the accumulation result of the accumulation period PS, thereby generating image data DT.

[0079] The exposure controller 12 calculates, for example, Figure 5 Shown are time Tls(1), time Tle(1), time Tss(2) and time Tse(2).

[0080] Tls(n)=Tf(n)-TL / 2-TS / 2

[0081] Tle(n)=Tf(n)+TL / 2-TS / 2

[0082] Tss(n)=Tf(n)-TS

[0083] Tse(n)=Tf(n)

[0084] Here, n is a number indicating the number of cycles. Tf(n) is Figure 5 The synchronization interval shown is measured by the exposure controller 12. TL is the time length of the accumulation period PL and is stored in, for example, a control register. TS is the time length of the accumulation period PS and is stored in, for example, a control register. The data of the time length TL and the time length TS stored in the control register are desirably changeable. This makes it possible to adjust the dynamic range according to the brightness of the subject, for example.

[0085] Using these equations, time Tls(1), time Tle(1), time Tss(2), and time Tse(2) are as follows.

[0086] Tls(1)=Tf(1)-TL / 2-TS / 2

[0087] Tle(1)=Tf(1)+TL / 2-TS / 2

[0088] Tss(2)=Tf(2)-TS

[0089] Tse(2)=Tf(2)

[0090] For example, the exposure controller 12 measures the synchronization interval Tf(1) between the time t1 and the time t11 based on the synchronization signal SYNC, and calculates the time Tls(1) and Tle(1) using the synchronization interval Tf(1) and the time length TL and the time length TS stored in the control register. The exposure controller 12 thus sets the accumulation period PL having the long time length TL. In the same manner, the exposure control section 12 measures the synchronization interval Tf(2) between the time t11 and the time t21 based on the synchronization signal SYNC, and calculates the time Tss(2) and the time Tse(2) using the synchronization interval and the time length TS stored in the control register. The exposure controller 12 thus sets the accumulation period PS having the short time length TS.

[0091] Here, the center time tlc(n) of the accumulation period PL and the center time tsc(n) of the accumulation period PS are expressed as follows.

[0092] Tlc(n)=(Tls(n)+Tle(n)) / 2

[0093] =Tf(n)-TS / 2

[0094] Tsc(n)=(Tss(n)+Tse(n)) / 2

[0095] =Tf(n)-TS / 2

[0096] Therefore, if Figure 5 As shown in (E), the time between the center moment of the accumulation period PL with a long time length TL between time t13 and time t14 and the center moment of the accumulation period PS with a time length TS between time t23 and time t24 is equal to the time of the synchronization interval Tf; and the time between the center moment of the accumulation period PS with a time length TS between time t23 and time t24 and the center moment of the accumulation period PL with a long time length TL between time t33 and time t34 is equal to the time of the synchronization interval Tf. In other words, the time length between the respective center moments of the accumulation periods P (accumulation period PL and accumulation period PS) adjacent to each other on the time axis is equal to the time of the synchronization interval Tf and is constant. Therefore, as will be described below, in the imaging device 1, the deviation between the center position of the subject 9 in the image DL generated by the TDI processing 100L and the center position of the subject 9 in the image DS generated by the TDI processing 100S can be suppressed.

[0097] Figure 7 is an example of an image DL generated by the TDI process 100L and an image DS generated by the TDI process 100S. Figure 5As shown, the time length TL of the accumulation period PL is longer than the time length TS of the accumulation period PS. Therefore, in the image DL generated by the TDI process 100L, the subject 9 is more visible in the moving direction ( Figure 7 In the horizontal direction, it is slightly wider. Figure 7 As shown in FIG. 1 , the center of gravity position of the subject 9 in the image DL generated by the TDI process 100L and the center of gravity position of the subject 9 in the image DS generated by the TDI process 100S coincide with each other in the moving direction of the subject 9. In other words, Figure 5 As shown, in the imaging device 1, the time length between the respective center moments of the accumulation periods P adjacent to each other on the time axis is equal to the time of the synchronization interval Tf and is constant. Therefore, the center of gravity position of the subject 9 in the image DL and the center of gravity position of the subject 9 in the image DS can be made to coincide with each other. Therefore, the HDR processor 94 at the later stage in the imaging device 1 can synthesize the image DL and the image DS whose center of gravity positions coincide with each other as they are through HDR processing. This makes it possible to improve the quality of the image generated by HDR processing compared with the comparative example to be described below.

[0098] Next, the effects of this embodiment will be described in comparison with some comparative examples.

[0099] (First Comparative Example)

[0100] First, an image pickup device 1R according to a first comparative example will be described. The image pickup device 1R is configured to set an accumulation period PS having a short time length TS for pixel rows L1 to L4 of the pixel array 11, and to set an accumulation period PL having a long time length TL for pixel rows L5 to L8 of the pixel array 11. The image pickup device 1R is similar to the image pickup device 1 ( Figure 2 )A similar approach includes: an exposure controller 12R and a TDI processor 15R.

[0101] Figure 8 is an example of TDI processing performed in the image pickup device 1R. The exposure controller 12R sets an accumulation period PS having a short time length TS for the pixel rows L1 to L4 of the pixel array 11, and sets an accumulation period PL having a long time length TL for the pixel rows L5 to L8 of the pixel array 11. Therefore, the images P1 to P8 respectively include: Figure 8 An image surrounded by a solid line in and generated based on an accumulation result of an accumulation period PS having a short time length TS; and an image generated by Figure 8 An image surrounded by the dotted line in and generated based on the accumulation result of the accumulation period PL having the long time length TL.

[0102] The TDI processor 15R performs the TDI processing 100RS using the pixel value based on the accumulation result of the accumulation period PS. In this example, the TDI processor 15R performs the TDI processing 100RS by adding the row image associated with the most upstream pixel row L1 in the image P1, the row image associated with the second pixel row L2 in the image P2, the row image associated with the third pixel row L3 in the image P3, and the row image associated with the fourth pixel row L4 in the image P4 in units of pixels.

[0103] In a similar manner, the TDI processor 15R performs the TDI processing 100RL using the pixel value based on the accumulation result of the accumulation period PL. In this example, the TDI processor 15R performs the TDI processing 100RL by adding the row image associated with the fifth pixel row L5 in the image P5, the row image associated with the sixth pixel row L6 in the image P6, the row image associated with the seventh pixel row L7 in the image P7, and the row image associated with the most downstream pixel row L8 in the image P8 in units of pixels.

[0104] Fig. 9 An example of an accumulation period P in an image pickup device 1R is shown, wherein (A) shows a waveform of a synchronization signal SYNC, and (B) shows an accumulation operation performed in a pixel array 11. The exposure controller 12R sets an accumulation period PL having a long time length TL and an accumulation period PS having a short time length TS based on the synchronization signal SYNC. Specifically, for example, the exposure controller 12R sets an accumulation period PL starting at time t41 and ending at time t43, and sets an accumulation period PS starting at time t42 and ending at time t43. In this example, the time length between the respective center moments of the accumulation periods PL adjacent to each other on the time axis is also equal to the time of the synchronization interval Tf, and is constant, and the time length between the respective center moments of the accumulation periods PS adjacent to each other on the time axis is also equal to the time of the synchronization interval Tf, and is constant.

[0105] However, in this example, the center time of the accumulation period PL and the center time of the accumulation period PS are offset from each other. Fig.10 As shown, there is a deviation Δ between the position of the center of gravity of the subject 9 in the image DL generated by the TDI process 100RL and the position of the center of gravity of the subject 9 in the image DS generated by the TDI process 100RS. Therefore, the HDR processor 94 at the subsequent stage of the imaging device 1R first has to perform image correction processing based on the image DL and the image DS in such a way that the position of the center of gravity of the subject 9 coincides with each other, and combine the two corrected images by HDR processing. Therefore, the image correction processing may degrade the image quality.

[0106] In addition, the image pickup device 1R sets an accumulation period PS with a short time length TS for the pixel rows L1 to L4 of the pixel array 11, and sets an accumulation period PL with a long time length TL for the pixel rows L5 to L8 of the pixel array 11. Therefore, the pixel controller 13 must control, for example, the accumulation operation of a plurality of light receiving pixels PIX included in the pixel rows L1 to L4 and the accumulation operation of a plurality of light receiving pixels PIX included in the pixel rows L5 to L8 by using different control signals. Therefore, for example, the wiring of the control signal of the pixel array 11 becomes complicated. In particular, in a row sensor, it is desirable that the light receiving pixels PIX are arranged close to each other. In this case, for example, in the pixel array 11, the space for wiring between the light receiving pixels PIX is reduced. Therefore, it is difficult to arrange the wiring. For example, in the case of setting complicated wiring, this affects the image quality.

[0107] In contrast, the camera device 1 according to the present embodiment is capable of causing the center of gravity position of the subject 9 in the image DL and the center of gravity position of the subject 9 in the image DS to coincide with each other. The HDR processor 94 is therefore capable of combining the image DL and the image DS whose center of gravity positions coincide with each other as is, by HDR processing, without performing image correction processing. This makes it possible to improve the quality of the image generated by the HDR processing. In addition, the camera device 1 sets the accumulation period PL or the accumulation period PS for all pixel rows L1 to L8 included in the pixel array 11 in a time-division manner. The pixel controller 13 is therefore capable of controlling the accumulation operation of all light receiving pixels PIX using the same control signal, for example. This makes it possible to simplify the wiring of the control signal of the pixel array 11 and reduce the possibility of reduced image quality due to complex wiring.

[0108] (Second Comparative Example)

[0109] Next, an image pickup device 1S according to a second comparative example will be described. The image pickup device 1S is obtained by changing the timing of the exposure period PL and the exposure period TS of the image pickup device 1R according to the first comparative example. The image pickup device 1S is similar to the image pickup device 1 ( Figure 2 )A similar approach includes an exposure controller 12S and a TDI processor 15S.

[0110] Fig.111 is an example of the accumulation period P of the image pickup device 1S. The exposure controller 12S sets the accumulation period PL having a long time length TL and the accumulation period PS having a short time length TS based on the synchronization signal SYNC. Specifically, for example, the exposure controller 12S sets the accumulation period PL starting at time t51 and ending at time t54, and sets the accumulation period PS starting at time t52 and ending at time t53. In this example, the center time of the accumulation period PL and the center time of the accumulation period PS are made to coincide with each other. Therefore, in the image pickup device 1S, it is possible to perform the operation in a manner similar to that of the image pickup device 1 ( Figure 7 ) in a manner similar to the case of FIG. 2 . The center-of-gravity position of the subject 9 in the image DL and the center-of-gravity position of the subject 9 in the image DS are made to coincide with each other.

[0111] However, in this case, the multiple light receiving pixels PIX included in the pixel rows L1 to the pixel rows L4 start the AD conversion operation from the moment t53 when the accumulation period PS ends, and the multiple light receiving pixels PIX included in the pixel rows L5 to the pixel rows L8 start the AD conversion operation from the moment t54 when the accumulation period PL ends. Therefore, the pixel controller 13 must control, for example, the AD conversion operation of the multiple light receiving pixels PIX included in the pixel rows L1 to the pixel rows L4 and the AD conversion operation of the multiple light receiving pixels PIX included in the pixel rows L5 to the pixel rows L8 by using different control signals. Therefore, for example, the wiring of the control signal of the pixel array 11 becomes complicated. For example, in the case of setting a complicated wiring, this affects the image quality. In addition, in this way, since the timings of the AD conversion operations are different from each other, for example, the power supply noise caused by the AD conversion operation related to the multiple light receiving pixels PIX included in the pixel rows L1 to the pixel rows L4 affects the accumulation operation of the multiple light receiving pixels PIX included in the pixel rows L5 to the pixel rows L8, and the image quality is reduced.

[0112] In contrast, the image pickup device 1 according to the present embodiment sets the accumulation period PL or the accumulation period PS for all the pixel rows L1 to L8 included in the pixel array 11 in a time-division manner, and thus can determine the moment of the AD conversion operation of the plurality of light receiving pixels PIX included in all the pixel rows L1 to L8. For example, the pixel controller 13 can therefore use the same control signal to control the AD conversion operation of all the light receiving pixels PIX. This makes it possible to simplify the wiring of the control signals of the pixel array 11 and reduce the possibility of reduced image quality due to complex wiring. In addition, since the moments of the AD conversion operations can be made to coincide with each other in this way, the power supply noise generated by the AD conversion operation of a certain light receiving pixel PIX does not affect the accumulation operation of other light receiving pixels PIX. Therefore, the possibility of reduced image quality can be reduced.

[0113] In this way, the image pickup device 1 sets the time length of the accumulation period P to one of the short time length TS or the long time length TL in a time-division and alternating manner, and performs an accumulation operation in which each of the plurality of light-receiving pixels PIX included in the pixel array 11 accumulates a charge corresponding to the light-receiving amount during the accumulation period P. Then, for example, as Figure 4A As shown, a plurality of pixel values ​​based on the accumulation result of the pixel row L1 of the accumulation period PS having a short time length TS and a plurality of pixel values ​​based on the accumulation result of the pixel row L3 of another accumulation period PS are added to each other, and, for example, Figure 4B As shown, a plurality of pixel values ​​based on the accumulation result of the pixel row L1 of the accumulation period PL having a long time length TL and a plurality of pixel values ​​based on the accumulation result of the pixel row L3 of another accumulation period PL are added to each other, thereby generating image data DT. If the accumulation period P is an accumulation period PS having a short time length TS, the pixel array 11 is capable of capturing, for example, the bright portion of the subject 9 with high image quality, and if the accumulation period P is an accumulation period PL having a long time length TL, the pixel array 11 is capable of capturing, for example, the dark portion of the subject 9 with high image quality. Therefore, the imaging device 1 is capable of achieving a wide dynamic range. In addition, the imaging device 1 is capable of improving sensitivity by adding a plurality of pixel values ​​through TDI processing. Therefore, the imaging device 1 is capable of improving image quality.

[0114] Specifically, the image pickup device 1 alternately sets the time length of the accumulation time P to one of the short time length TS and the long time length TL. Therefore, the image pickup device 1 can simplify the wiring in the pixel array 11 and can reduce the possibility of deterioration of image quality due to complicated wiring. In addition, since the power supply noise generated by the AD conversion operation does not affect the accumulation operation, the image quality can be improved.

[0115] Furthermore, in the imaging device 1, the time length between the respective center moments of two accumulation periods P adjacent to each other on the time axis is made constant. Therefore, the imaging device 1 can make the center of gravity position of the subject 9 in the image DL generated by the TDI process 100L and the center of gravity position of the subject 9 in the image DS generated by the TDI process 100S coincide with each other. Therefore, for example, in the case of combining the image DL and the image DS by the HDR process, the image DL and the image DS can be combined as they are without performing image correction processing for adjusting the center position. This makes it possible to improve the image quality of the image generated by the HDR process.

[0116] [Effect]

[0117] As described above, in the present embodiment, the time length of the accumulation period is alternately set to one of a short time length or a long time length, and a plurality of light receiving pixels included in the pixel array perform an accumulation operation of accumulating charges corresponding to the light receiving amount during the accumulation period. Then, for example, a plurality of pixel values ​​based on the accumulation result of the pixel row L1 of the accumulation period PS having a short time length and a plurality of pixel values ​​based on the accumulation result of the pixel row L3 of another accumulation period PS are added to each other, and for example, a plurality of pixel values ​​based on the accumulation result of the pixel row L1 of the accumulation period PL having a long time length and a plurality of pixel values ​​based on the accumulation result of the pixel row L3 of another accumulation period PL are added to each other, thereby generating image data. Therefore, it is possible to improve image quality.

[0118] In the present embodiment, the time length between the respective center times of two accumulation periods P adjacent to each other on the time axis is constant. This enables improvement in image quality.

[0119] [Modification 1]

[0120] In the above-described embodiment, the accumulation period PS having a short time length TS and the accumulation period PL having a long time length TL are alternately set; however, the present invention is not limited thereto, and, for example, the accumulation period PS and the accumulation period PL may be set in a predetermined order. Hereinafter, the image pickup device 1A according to this modification will be described in detail. The image pickup device 1A is similar to the image pickup device 1 ( Figure 2 )A similar approach includes: exposure controller 12A and TDI processor 15A.

[0121] Fig.12 An example of the accumulation period P of the image pickup apparatus 1A is shown. Fig.13 An example of TDI processing to be performed by the image pickup apparatus 1A is shown.

[0122] like Fig.12 As shown, the exposure controller 12A repeatedly sets the accumulation period PS, the accumulation period PS, the accumulation period PL, and the accumulation period PL in sequence based on the synchronization signal SYNC. Specifically, for example, the exposure controller 12A sets the accumulation period PS starting at time t61 and ending at time t62, sets the accumulation period PS starting at time t63 and ending at time t64, sets the accumulation period PL starting at time t65 and ending at time t66, and sets the accumulation period PL starting at time t67 and ending at time t68. Also in this example, the time length between the respective center times of the accumulation periods P adjacent to each other on the time axis is equal to the time of the synchronization interval Tf, and is constant.

[0123] exist Fig.13In the figure, images P1, P2, P5 and P6 respectively surrounded by solid lines are images generated based on the accumulation results of the accumulation period PS with a short time length TS, and images P3, P4, P7 and P8 respectively surrounded by dotted lines are images generated based on the accumulation results of the exposure time PL with a long time length TL.

[0124] The TDI processor 15A performs the TDI processing 100S using the pixel value based on the accumulation result of the accumulation period PS. In this example, the TDI processor 15A performs the TDI processing 100S by adding the row image associated with the most upstream pixel row L1 in the image P1, the row image associated with the second pixel row L2 in the image P2, the row image associated with the fifth pixel row L5 in the image P5, and the row image associated with the sixth pixel row L6 in the image P6 in units of pixels.

[0125] In a similar manner, the TDI processor 15A performs the TDI process 100L using the pixel value based on the accumulation result of the accumulation period PL. In this example, the TDI processor 15A performs the TDI process 100L by adding the row image associated with the third pixel row L3 in the image P3, the row image associated with the fourth pixel row L4 in the image P4, the row image associated with the seventh pixel row L7 in the image P7, and the row image associated with the most downstream pixel row L8 in the image P8 in units of pixels.

[0126] [Modification 2]

[0127] In the above-described embodiment, two accumulation periods PS and PL are alternately set; however, the present invention is not limited thereto, and, for example, three or more accumulation periods P may be set in a predetermined order. Hereinafter, the image pickup device 1B according to this modification will be described in detail. The image pickup device 1B is similar to the image pickup device 1 ( Figure 2 ) includes a pixel array 11B and an exposure controller 12B and a TDI processor 15B in a similar manner. In this example, a plurality of light receiving pixels PIX included in the pixel array 11B are divided into six pixel rows L.

[0128] Fig.14 FIG. 2 shows an example of the accumulation period P of the imaging device 1B. Fig.15 An example of TDI processing to be performed by the imaging apparatus 1B is shown.

[0129] like Fig.14As shown, the exposure controller 12A repeatedly sets the accumulation period PS with a short time length TS, the accumulation period PM with a medium time length TM, and the accumulation period PL with a long time length TL in the following order based on the synchronization signal SYNC. Also in this example, the time length between the respective center moments of the accumulation periods P adjacent to each other on the time axis is equal to the time of the synchronization interval Tf and is constant.

[0130] exist Fig.15 In the figure, images P1 and P4 respectively surrounded by solid lines are images generated based on the accumulation results of the accumulation period PS with a short time length TS, and images P2 and P5 respectively surrounded by long dashed lines are images generated based on the accumulation results of the exposure period PM with a medium time length TM, and images P3 and P6 respectively surrounded by short dashed lines are images generated based on the accumulation results of the accumulation period PL with a long time length TL.

[0131] The TDI processor 15B performs TDI processing 100S using the pixel value based on the accumulation result of the accumulation period PS. In this example, the TDI processor 15B performs TDI processing 100S by adding the row image associated with the most upstream pixel row L1 in the image P1 and the row image associated with the fourth pixel row L4 in the image P4 in units of pixels.

[0132] In a similar manner, the TDI processor 15B performs the TDI processing 100M using the pixel value based on the accumulation result of the accumulation period PM. In this example, the TDI processor 15B performs the TDI processing 100M by adding the row image associated with the second pixel row L2 in the image P2 and the row image associated with the fifth pixel row L5 in the image P5 in units of pixels.

[0133] In a similar manner, the TDI processor 15B performs the TDI processing 100L using the pixel value based on the accumulation result of the accumulation period PL. In this example, the TDI processor 15B performs the TDI processing 100L by adding the row image associated with the third pixel row L3 in the image P3 and the row image associated with the sixth pixel row L6 in the image P6 in units of pixels.

[0134] [Variation 3]

[0135] In the above-described embodiment, the light receiving pixel PIX performs an accumulation operation and an AD conversion operation; however, the present invention is not limited thereto. Alternatively, for example, a circuit that performs an AD conversion operation may be provided separately from the light receiving pixel. Hereinafter, the imaging device 1C according to this modification will be described in detail.

[0136] Fig.16An example of a configuration of an image pickup device 1C is shown. The image pickup device 1C includes a pixel array 11C, an exposure controller 12C, a pixel controller 13C, a GS (Global Shutter) memory 14C, and an AD converter 18C.

[0137] The pixel array 11C includes a plurality of light receiving pixels PIXC arranged in a matrix form. Each of the plurality of light receiving pixels PIXC performs an accumulation operation of accumulating charges corresponding to the amount of light reception during an accumulation period P. In other words, while the light receiving pixels PIX according to the above-described embodiment perform an accumulation operation and an AD conversion operation, the light receiving pixels PIXC according to this modification only perform an accumulation operation. The accumulation operation of the plurality of light receiving pixels PIXC is performed based on an instruction from the pixel controller 13C.

[0138] The exposure controller 12C is configured based on the transmission controller 92 ( Figure 1 ) to control the accumulation operation to be performed in the pixel array 11C. Specifically, the exposure controller 12C sets the accumulation period PL having a long time length TL and the accumulation period PS having a short time length TS in a time-division and alternating manner based on the synchronization signal SYNC. Then, the exposure controller 12C generates an exposure start signal SST indicating the start time of the accumulation period P and an exposure end signal SED indicating the end time of the accumulation period P, and supplies these signals to the pixel controller 13C. In addition, the exposure controller 12C generates an exposure type signal EX indicating which of the processing related to the accumulation result of the accumulation time PL or the processing related to the accumulation result of the accumulation time PS is to be performed.

[0139] The pixel controller 13C is configured to control the accumulation operation by driving the plurality of light receiving pixels PIXC included in the pixel array 11C based on the exposure start signal SST and the exposure end signal SED supplied from the exposure controller 12C. In addition, after the accumulation operation ends, the pixel controller 13C also has a function of controlling the operation of transferring the charges accumulated in the plurality of light receiving pixels PIXC to the GS memory 14C.

[0140] The GS memory 14C is an analog memory, is provided in the vicinity of the pixel array 11C, and is configured to temporarily store charges supplied from a plurality of light-receiving pixels PIXC included in the pixel array 11C.

[0141] The AD converter 18C is configured to generate a plurality of pixel values ​​for one row by performing AD conversion based on the charge for one row read from the GS memory 14C. Here, the AD converter 18C corresponds to a specific example of an "AD converter" according to the present invention.

[0142] [Variation 4]

[0143] In the above-described embodiment, the camera 1 outputs the image data DT including the image DL generated by the TDI process 100L and the image DS generated by the TDI process 100S, and the HDR processor 94 provided separately from the camera 1 performs HDR processing based on the image data DT. However, the present invention is not limited thereto. Alternatively, for example, as in Fig.17 As in the illustrated camera 1D, an HDR processor 19D may be provided in the camera 1D, and the HDR processor 19D may perform HDR processing based on the image data DT and output image data DT2 generated by the HDR processing.

[0144] [Other Modifications]

[0145] Furthermore, two or more modifications may be combined.

[0146] Although the present invention has been described above with reference to exemplary embodiments and modifications, these embodiments and modifications should not be construed as limiting the scope of the present invention and may be modified in various ways.

[0147] For example, in the above-described embodiment, although the pixel array 11 is provided with eight pixel rows L, the present invention is not limited thereto, and instead, for example, the number of the plurality of pixel rows L may be seven or less, or may be nine or more.

[0148] For example, in the above-described embodiment, the imaging device 1 performs an imaging operation based on the synchronization signal SYNC every time the image of the subject 9 advances by one pixel row L on the imaging plane S; however, the present invention is not limited thereto. Alternatively, for example, the imaging device may perform an imaging operation every time the image of the subject 9 advances by two or more pixel rows L on the imaging plane S.

[0149] For example, in the above embodiment, if Figure 1 As shown, the conveying controller 92 generates a synchronization signal SYNC, and the camera device 1 performs a camera operation according to the synchronization signal SYNC. However, the present invention is not limited to this. Alternatively, for example, the camera device can generate a synchronization signal SYNC and perform a camera operation based on the synchronization signal SYNC, and the conveying controller can control the conveying operation of the belt conveyor 91 based on the synchronization signal SYNC.

[0150] For example, in the above embodiment, Figure 1 In the embodiment, the imaging device 1 is fixed and the subject 9 is moving; however, the present invention is not limited thereto. Alternatively, for example, the subject 9 may be fixed and the imaging device 1 may be moving.

[0151] It should be understood that the effects described herein are merely examples and are not limited to those described herein. The present invention may also include any effects other than those described herein.

[0152] It should be noted that the present technology may have the following configuration. According to the present technology having the following configuration, image quality can be improved. (1)

[0154] A camera device, comprising:

[0155] a pixel array including a plurality of light-receiving pixels divided into a plurality of pixel rows and accumulating charges corresponding to a light-receiving amount during an accumulation period, the plurality of pixel rows including a first pixel row and a second pixel row arranged in parallel along a first direction;

[0156] an exposure controller that sets a time length of an accumulation period of the plurality of light receiving pixels to one of a plurality of time lengths including a first time length and a second time length so that the plurality of time lengths are repeated in a predetermined order; and

[0157] a processor that generates image data based on the accumulation results in the plurality of light receiving pixels, wherein

[0158] The accumulation period includes a first accumulation period and a second accumulation period each having the first time length, and a third accumulation period and a fourth accumulation period each having the second time length; and

[0159] The processor generates image data by adding a plurality of pixel values ​​based on the accumulation result in the first pixel row during the first accumulation period and a plurality of pixel values ​​based on the accumulation result in the second pixel row during the second accumulation period, and by adding a plurality of pixel values ​​based on the accumulation result in the first pixel row during the third accumulation period and a plurality of pixel values ​​based on the accumulation result in the second pixel row during the fourth accumulation period. (2)

[0161] The imaging device according to (1), wherein a time length between respective center times of two adjacent accumulation periods is constant. (3)

[0163] The imaging device according to (1) or (2), wherein:

[0164] The exposure controller changes the time length of the accumulation period every time a predetermined period elapses, and

[0165] A time difference between a center time of the first accumulation period and a center time of the third accumulation period is equal to a time length of the predetermined period. (4)

[0167] The imaging device according to (3), wherein the exposure controller sets the time length of the accumulation period based on a synchronization signal supplied from the outside. (5)

[0169] The imaging device according to (4), wherein:

[0170] The synchronization signal includes a plurality of pulses, the plurality of pulses including a first pulse and a second pulse; and

[0171] The exposure controller

[0172] The start time of the first accumulation period and the end time of the first accumulation period are set based on the first pulse, and

[0173] The start time of the third accumulation period and the end time of the third accumulation period are set based on the second pulse. (6)

[0175] The imaging device according to any one of (1) to (5), wherein the processor

[0176] include:

[0177] a first storage unit associated with the first time length, and

[0178] a second storage unit associated with the second time length;

[0179] adding a plurality of pixel values ​​based on the accumulation result in the first pixel row during the first accumulation period and a plurality of pixel values ​​based on the accumulation result in the second pixel row during the second accumulation period using the first storage section; and

[0180] A plurality of pixel values ​​based on the accumulation result in the first pixel row in the third accumulation period and a plurality of pixel values ​​based on the accumulation result in the second pixel row in the fourth accumulation period are added using the second storage section. (7)

[0182] An imaging device according to any one of (1) to (6), wherein the image data includes first image data based on an accumulation result of the accumulation period having the first time length and second image data based on an accumulation result of the accumulation period having the second time length. (8)

[0184] The image pickup device according to any one of (1) to (7), wherein each of the plurality of light receiving pixels converts an analog signal corresponding to the charge accumulated in the accumulation period into the pixel value, the pixel value being a digital value. (9)

[0186] An imaging device according to (8), wherein each of the plurality of light receiving pixels accumulates a charge corresponding to the light reception amount during the accumulation period, and, within a predetermined period after the accumulation period, converts the analog signal corresponding to the charge accumulated during the accumulation period into the pixel value which is a digital value. (10)

[0188] The image pickup device according to any one of (1) to (7), further including an AD converter that converts an analog signal corresponding to the charge accumulated in each of the plurality of light receiving pixels into the pixel value, the pixel value being a digital value. (11)

[0190] The imaging device according to any one of (1) to (10), wherein the exposure controller sets the accumulation period every time an image of a subject advances by a predetermined number of pixel rows in the first direction on an imaging plane of the pixel array.

[0191] This application claims priority from Japanese Patent Application JP2020-108113 filed with the Japan Patent Office on June 23, 2020, the entire contents of which are incorporated herein by reference.

[0192] It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions may be made according to design requirements and other factors as long as they are within the scope of the appended claims or the equivalents thereof.

Claims

1. A camera device, comprising: a pixel array including a plurality of light-receiving pixels divided into a plurality of pixel rows and accumulating charges corresponding to a light-receiving amount during an accumulation period, the plurality of pixel rows including a first pixel row and a second pixel row arranged in parallel along a first direction; an exposure controller that sets a time length of an accumulation period of the plurality of light receiving pixels to one of a plurality of time lengths including a first time length and a second time length so that the plurality of time lengths are repeated in a predetermined order; as well as a processor that generates image data based on the accumulation results in the plurality of light receiving pixels, wherein The accumulation period includes a first accumulation period and a second accumulation period each having the first time length, and a third accumulation period and a fourth accumulation period each having the second time length; and The processor generates image data by adding a plurality of pixel values ​​based on the accumulation result in the first pixel row during the first accumulation period and a plurality of pixel values ​​based on the accumulation result in the second pixel row during the second accumulation period, and by adding a plurality of pixel values ​​based on the accumulation result in the first pixel row during the third accumulation period and a plurality of pixel values ​​based on the accumulation result in the second pixel row during the fourth accumulation period.

2. The imaging device according to claim 1, wherein: The time length between the respective center times of two adjacent accumulation periods is constant.

3. The imaging device according to claim 1, wherein: The exposure controller changes the time length of the accumulation period every time a predetermined period elapses, and A time difference between a center time of the first accumulation period and a center time of the third accumulation period is equal to a time length of the predetermined period.

4. The imaging device according to claim 3, wherein: The exposure controller sets the time length of the accumulation period based on a synchronization signal supplied from the outside.

5. The imaging device according to claim 4, wherein: The synchronization signal includes a plurality of pulses, the plurality of pulses including a first pulse and a second pulse; and The exposure controller The start time of the first accumulation period and the end time of the first accumulation period are set based on the first pulse, and The start time of the third accumulation period and the end time of the third accumulation period are set based on the second pulse.

6. The imaging device according to any one of claims 1 to 5, wherein: The processor include: a first storage unit associated with the first time length, and a second storage unit associated with the second time length; adding a plurality of pixel values ​​based on the accumulation result in the first pixel row during the first accumulation period and a plurality of pixel values ​​based on the accumulation result in the second pixel row during the second accumulation period using the first storage section; and A plurality of pixel values ​​based on the accumulation result in the first pixel row in the third accumulation period and a plurality of pixel values ​​based on the accumulation result in the second pixel row in the fourth accumulation period are added using the second storage section.

7. The imaging device according to any one of claims 1 to 5, wherein: The image data includes first image data based on an accumulation result of the accumulation period having the first time length and second image data based on an accumulation result of the accumulation period having the second time length.

8. The imaging device according to any one of claims 1 to 5, wherein: Each of the plurality of light receiving pixels converts an analog signal corresponding to the charge accumulated during the accumulation period into the pixel value, which is a digital value.

9. The imaging device according to claim 8, wherein: Each of the plurality of light receiving pixels accumulates charges corresponding to the light reception amount during the accumulation period, and converts the analog signal corresponding to the charges accumulated during the accumulation period into the pixel value as a digital value during a predetermined period after the accumulation period. 10 . The image pickup device according to claim 1 , further comprising an AD converter that converts an analog signal corresponding to the electric charge accumulated in each of the plurality of light-receiving pixels into the pixel value, the pixel value being a digital value.

11. The imaging device according to any one of claims 1 to 5, wherein: The exposure controller sets the accumulation period every time an image of a subject advances by a predetermined number of pixel rows in the first direction on an imaging plane of the pixel array.

Images