Imaging device and imaging apparatus

Abstract

To improve a frame rate of an imaging element.SOLUTION: The imaging element includes a first photoelectric conversion unit, a second photoelectric conversion unit, a first signal line to which a first signal based on a charge generated by the first photoelectric conversion unit is output, and a second signal line to which a second signal based on a charge generated by the second photoelectric conversion unit is output, the signal processing device includes a first A / D conversion unit that converts an input first signal from an analog signal to a digital signal, a second A / D conversion unit that is connected to a second signal line and converts an input second signal from an analog signal to a digital signal, and a first switch that switches between connection and disconnection of a first portion of the first signal line between a first position where the first photoelectric conversion unit and the first signal line are connected and the first A / D conversion unit and a second portion of the first signal line between a second position where the second photoelectric conversion unit and the second signal line are connected and the second A / D conversion unit.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to an imaging element and an imaging device. [Background technology]

[0002] Various methods have been proposed to improve the frame rate of an imaging device (for example, Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] International Publication No. 2020 / 095544 Summary of the Invention

[0004] According to a first aspect of the disclosure, an imaging element includes a first photoelectric conversion unit that photoelectrically converts incident light, a second photoelectric conversion unit that photoelectrically converts incident light, a first signal line that outputs a first signal based on charges generated by the first photoelectric conversion unit, a second signal line that outputs a second signal based on charges generated by the second photoelectric conversion unit, a first A / D conversion unit that is electrically connected to the first signal line and converts the input first signal from an analog signal to a digital signal, and a second A / D conversion unit that is electrically connected to the second signal line and converts the input first signal from an analog signal to a digital signal. The digital signal processing device includes a second A / D conversion unit that converts the second signal from an analog signal to a digital signal, and a first switch that switches between connection and disconnection between a first portion of the first signal line that is located between the first A / D conversion unit and a first position where the first photoelectric conversion unit and the first signal line are electrically connected, and a first portion of the second signal line that is located between the second A / D conversion unit and a second position where the second photoelectric conversion unit and the second signal line are electrically connected, in order to add the first signal and the second signal.

[0005] According to a second aspect of the disclosure, the imaging device includes the imaging element and a control unit that, when the frame rate is equal to or greater than a predetermined threshold, turns on the first switch to connect the first portion of the first signal line and the first portion of the second signal line.

[0006] According to a third aspect of the disclosure, the imaging element includes a plurality of signal lines, each of which has one end connected to a first A / D conversion unit and the other end connected to a second A / D conversion unit, and a plurality of photoelectric conversion units are connected to each of the plurality of signal lines, and when signals based on charges generated in two of the plurality of photoelectric conversion units are output to the signal line at the same timing, each of the plurality of signal lines connects a photoelectric conversion unit, of the two photoelectric conversion units, that is electrically closer to the first A / D conversion unit to the first A / D conversion unit, and The device has a switch that connects a photoelectric conversion unit that is electrically close to the second A / D conversion unit to the second A / D conversion unit, and is provided with a first switching unit that can switch whether to add up the signals output to the first A / D conversion unit when signals based on charges generated in two of the multiple photoelectric conversion units are output to corresponding signal lines at the same timing for two or more of the multiple signal lines, and a second switching unit that can switch whether to add up the signals output to the second A / D conversion unit.

[0007] The configurations of the embodiments described below may be modified as appropriate, and at least a portion of the configuration may be replaced with other components. Furthermore, components that are not particularly limited in terms of their placement may be placed in any position that can achieve their function, not limited to the placement disclosed in the embodiments. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a diagram schematically illustrating an example of the configuration of a digital camera equipped with an image sensor according to the first embodiment. [Figure 2] FIG. 2 is a diagram illustrating a schematic configuration of the imaging element according to the first embodiment. [Figure 3]3A and 3B are diagrams for explaining source follower addition. [Figure 4] FIG. 4 is a diagram showing the configuration of an imaging element according to a comparative example. [Figure 5] FIG. 5 is a diagram showing the details of the configuration of the imaging element according to the first embodiment. [Figure 6] FIG. 6 is a time chart showing the operation of the image sensor when source follower addition is performed in the first embodiment. [Figure 7] FIG. 7 is a timing chart for explaining a case where one horizontal synchronization signal period is time-divided into three periods and AD conversion is performed in the image sensor according to the first embodiment. [Figure 8] FIG. 8 is a diagram showing the configuration of an image sensor according to the second embodiment. [Figure 9] FIG. 9 is a timing chart illustrating the operation of the image sensor according to the second embodiment when source follower addition is performed. [Figure 10] FIG. 10 is a diagram showing the configuration of an image sensor according to the third embodiment. [Figure 11] FIG. 11 is a timing chart for explaining the operation of the image sensor according to the third embodiment when source follower addition is performed. [Figure 12] FIG. 12 is a diagram showing the configuration of an image sensor according to the fourth embodiment. [Figure 13] FIG. 13 is a timing chart illustrating the operation of the image sensor according to the fourth embodiment when source follower addition is performed. DETAILED DESCRIPTION OF THE INVENTION

[0009] First Embodiment A digital camera 1 (hereinafter referred to as camera 1) equipped with an image sensor 21 according to a first embodiment will be described below with reference to FIGS. 1 to 6. Note that an XYZ Cartesian coordinate system is appropriately provided in the drawings below to facilitate explanation and understanding. In this coordinate system, the direction from the subject toward the camera body 2 in a camera position (hereinafter referred to as the normal position) when a photographer takes a landscape image with the optical axis OA horizontal is defined as the +Z direction. Also, the direction toward the right side as viewed from the camera body 2 in the normal position is defined as the +X direction. Also, the direction toward the upper side in the normal position is defined as the +Y direction. Note that the scales of the shapes, lengths, thicknesses, etc. of the various parts shown in the embodiments do not necessarily correspond to the actual objects, and some elements may be omitted from the drawings to facilitate understanding.

[0010] 1 is a diagram schematically illustrating an example configuration of a camera 1 equipped with an image sensor 21 according to the first embodiment. The camera 1 includes an interchangeable lens 3 and a camera body 2. The interchangeable lens 3 is attached to the camera body 2 via a lens mount (not shown). Note that the camera 1 may also be configured as an integrated lens camera rather than an interchangeable lens camera.

[0011] The interchangeable lens 3 includes an imaging optical system 31 including, for example, a zoom lens, a focus lens, an aperture, an anti-vibration lens, etc., and a lens control unit 32. The lens control unit 32 includes a CPU (Central Processing Unit) and peripheral components such as memory. The lens control unit 32 performs drive control of the focus lens and aperture, detects the positions of the zoom lens and focus lens, sends lens information to the camera body 2, and receives camera information from the camera body 2.

[0012] The camera body 2 includes, for example, an image sensor 21, an image processing unit 22, a body control unit 23, a display unit 24, an operation unit 25, and a recording unit 26.

[0013] The operation unit 25 includes a shutter button, operation members for various settings, etc. The display unit 24 is, for example, a liquid crystal monitor (also called a rear monitor) mounted on the rear surface of the camera body 2.

[0014] The body control unit 23 includes a CPU and peripheral components such as memory. The body control unit 23 controls the operation of the camera 1, such as driving and controlling the image sensor 21, reading out pixel signals from the image sensor 21, performing focus detection calculations and focusing the interchangeable lens 3, and displaying and recording image data. The body control unit 23 also communicates with the lens control unit 32, receiving lens information and transmitting camera information (such as defocus amount and aperture value).

[0015] In controlling the drive of the image sensor 21, the body control unit 23 determines whether or not to perform source follower addition at the image sensor 21 based on, for example, the frame rate set in the camera body 2. For example, the body control unit 23 determines to perform source follower addition when the frame rate is equal to or greater than a predetermined threshold, and determines not to perform source follower addition when the frame rate is less than the predetermined threshold. The body control unit 23 outputs various control signals to the image sensor 21 (drive control unit 43) according to whether or not to perform source follower addition. Note that in this embodiment, the necessity of source follower addition is determined based on the frame rate and the switch is controlled, but the factor determining the necessity of source follower addition is not limited to the frame rate. For example, the necessity of source follower addition may be determined based on a control parameter related to the frame readout time, and the switch may be controlled accordingly. The control parameter related to the frame readout time may include the frame rate, the curtain speed, the scan rate, etc.

[0016] The recording unit 26 has a card slot into which a storage medium such as a memory card can be inserted. The recording unit 26 stores the image data and various data generated by the image processing unit 22 in the storage medium inserted in the card slot. The recording unit 26 has an internal memory. In this case, the recording unit 26 can also record the image data and various data generated by the image processing unit 22 in the internal memory.

[0017] The image processing unit 22 is an image processing engine that performs various image processes on the pixel data input from the imaging element 21 .

[0018] The image sensor 21 is disposed on a planned image formation plane (planned focal plane) of the interchangeable lens 3, and photoelectrically converts the subject image formed by the interchangeable lens 3.

[0019] 2 is a diagram illustrating a schematic configuration of the image sensor 21 according to the first embodiment. The image sensor 21 includes a pixel array 50 including a plurality of pixels 51 arranged in a two-dimensional matrix, a vertical driver 42, a drive controller 43, a horizontal driver 44, a signal processor 45, and a memory 46.

[0020] The pixels 51 are assigned one of four pixels, namely, green pixels Gb, Gr, blue pixels B, and red pixels R, according to, for example, a Bayer array. Each pixel 51 includes a photoelectric conversion unit that converts light into electric charges, and outputs a signal based on the electric charges converted by the photoelectric conversion unit. The signal based on the electric charges converted by the photoelectric conversion unit is output to a vertical signal line connected to that pixel 51.

[0021] In this embodiment, eight vertical signal lines 52-1 to 52-8 are provided for each pixel column, and the pixels 51 included in each pixel column are connected to the vertical signal lines 52-1 to 52-8 in order from top to bottom.

[0022] The drive control unit 43 generates clock signals and control signals that serve as the basis for the operation of the vertical drive unit 42, signal processing unit 45, memory unit 46, horizontal drive unit 44, etc., and provides them to the vertical drive unit 42, signal processing unit 45, memory unit 46, horizontal drive unit 44, etc.

[0023] The vertical drive unit 42 supplies control signals such as a reset signal, a transfer signal, and a selection signal to each pixel 51 to control the operation of each pixel 51 .

[0024] The signal processing unit 45 performs predetermined signal processing on a signal (referred to as a pixel signal) that is output from each pixel 51 and corresponds to the charge accumulated in the photoelectric conversion unit, and outputs the signal to the memory unit 46. The configuration of the signal processing unit 45 will be described in detail later.

[0025] The memory unit 46 stores the pixel signals output from the signal processing unit 45 .

[0026] The horizontal drive unit 44 outputs the signal stored in the memory unit 46 to the image processing unit 22 in response to the scanning signal from the drive control unit 43 .

[0027] As described above, in this embodiment, eight vertical signal lines 52-1 to 52-8 are provided for each pixel column. This allows pixel signals to be simultaneously read out from eight rows of pixels 51 in one scan. Therefore, the pixel signal readout speed is eight times faster than when there is one vertical signal line.

[0028] In this embodiment, source follower addition is performed to further increase the readout speed of pixel signals. First, source follower addition will be described.

[0029] 3A and 3B are diagrams for explaining source follower addition. In the example shown in Fig. 3A and 3B, one vertical signal line 52 is provided for each pixel column.

[0030] When pixel signals are read out from all of the pixels 51-1 to 51-16, for example, one method is to read out pixel signals row by row in order starting from pixel 51-1, as shown in Fig. 3A. In Fig. 3A, the readout order is indicated by numbers to the right of the pixels 51-1 to 51-16.

[0031] 3B shows the readout order of pixel signals when source follower addition is performed. In FIG. 3B, pixel signals are read out at the same time from two pixels arranged in the same column but not adjacent to each other in the column direction to a vertical signal line 52. For example, the pixel signal of pixel 51-1 and the pixel signal of pixel 51-3 are read out at the same time to the same vertical signal line 52. Furthermore, the pixel signal of pixel 51-2 and the pixel signal of pixel 51-4 are read out at the same time to the vertical signal line 52.

[0032] Source follower addition is performed by outputting pixel signals from two pixels at the same time to one vertical signal line 52. By reading out pixel signals two rows at a time in this way, the speed at which pixel signals are read out from pixels 51-1 to 51-16 can be doubled compared to the case of FIG. 3A, and therefore the frame rate can also be doubled.

[0033] Next, problems that arise when performing source follower addition in an image sensor in which eight vertical signal lines are provided for each pixel column will be described with reference to Fig. 4. Fig. 4 is a diagram showing the configuration of an image sensor 21' according to a comparative example. The image sensor 21' according to the comparative example includes a plurality of pixels 51-1 to 51-16, a signal processing unit 45', and a memory unit 46.

[0034] The signal processing unit 45' includes A / D conversion units (ADC) 451-1 to 451-8 and correlated double sampling units (CDS) 452-1 to 452-8.

[0035] The ADCs 451-1 to 451-8 convert the noise signals and pixel signals input via the vertical signal lines 52-1 to 52-8 into digital signals and output them to the CDSs 452-1 to 452-8, respectively.

[0036] CDSs 452-1 to 452-8 perform correlated double sampling on the input digital signals, remove noise from the digital signals, and output the digital signals from which the noise has been removed to memories 461-1 to 461-8 included in memory unit 46, respectively.

[0037] 4, suppose that source follower addition is desired for pixel signals from pixels arranged in the same column but not adjacent to each other in the column direction (for example, pixel 51-1 and pixel 51-3). However, because pixel 51-1 is connected to vertical signal line 52-1 and pixel 51-3 is connected to vertical signal line 52-3, source follower addition cannot be performed for the pixel signals from pixel 51-1 and pixel 51-3.

[0038] It is possible to store each pixel signal in memories 461-1 to 461-8 and then perform digital addition, but in this case, only eight rows of pixel signals can be read out in one horizontal synchronization signal period, so the pixel signal readout speed is the same as when source follower addition is not performed, and the frame rate remains unchanged.

[0039] Therefore, the image sensor 21 according to this embodiment has a configuration for performing source follower addition of pixel signals from pixels connected to separate vertical signal lines.

[0040] Fig. 5 is a diagram showing the details of the configuration of the image sensor 21 according to this embodiment, in which only one pixel column is shown.

[0041] The pixels 51-1 to 51-8 are connected to vertical signal lines 52-1 to 52-8, respectively, and the pixels 51-9 to 51-16 are connected to vertical signal lines 52-1 to 52-8, respectively.

[0042] The signal processing unit 45 includes A / D conversion units (ADC) 451-1 to 451-8, correlated double sampling units (CDS) 452-1 to 452-8, and switches 453-1 to 453-4.

[0043] The ADCs 451-1 to 451-8 convert the noise signals and pixel signals input via the vertical signal lines 52-1 to 52-8 into digital signals and output them to the CDSs 452-1 to 452-8, respectively.

[0044] CDSs 452-1 to 452-8 perform correlated double sampling on the input digital signals, remove noise from the digital signals, and output the digital signals from which the noise has been removed to memories 461-1 to 461-8 included in memory unit 46, respectively.

[0045] The switch 453-1 switches between connection and disconnection a portion of the vertical signal line 52-1 located between the ADC 451-1 and a position P1-1 where the pixel 51-1 and the vertical signal line 52-1 are electrically connected, and a portion of the vertical signal line 52-3 located between the ADC 451-3 and a position P1-3 where the pixel 51-3 and the vertical signal line 52-3 are electrically connected. The switch 453-1 also switches between connection and disconnection a portion of the vertical signal line 52-1 located between the ADC 451-1 and a position P2-1 where the pixel 51-9 and the vertical signal line 52-1 are electrically connected, and a portion of the vertical signal line 52-3 located between the ADC 451-3 and a position P2-3 where the pixel 51-11 and the vertical signal line 52-3 are electrically connected.

[0046] The switch 453-2 switches between connection and disconnection a portion of the vertical signal line 52-2 located between the ADC 451-2 and a position P1-2 where the pixel 51-2 and the vertical signal line 52-2 are electrically connected, and a portion of the vertical signal line 52-4 located between the ADC 451-4 and a position P1-4 where the pixel 51-4 and the vertical signal line 52-4 are electrically connected. The switch 453-2 also switches between connection and disconnection a portion of the vertical signal line 52-2 located between the ADC 451-2 and a position P2-2 where the pixel 51-10 and the vertical signal line 52-2 are electrically connected, and a portion of the vertical signal line 52-4 located between the ADC 451-2 and a position P2-4 where the pixel 51-12 and the vertical signal line 52-4 are electrically connected.

[0047] The switch 453-3 switches between connection and disconnection a portion of the vertical signal line 52-5 located between the ADC 451-5 and a position P1-5 where the pixel 51-5 and the vertical signal line 52-5 are electrically connected, and a portion of the vertical signal line 52-7 located between the ADC 451-7 and a position P1-7 where the pixel 51-7 and the vertical signal line 52-7 are electrically connected. The switch 453-3 also switches between connection and disconnection a portion of the vertical signal line 52-5 located between the ADC 451-5 and a position P2-5 where the pixel 51-13 and the vertical signal line 52-5 are electrically connected, and a portion of the vertical signal line 52-7 located between the ADC 451-7 and a position P2-7 where the pixel 51-15 and the vertical signal line 52-7 are electrically connected.

[0048] The switch 453-4 switches between connection and disconnection between a portion of the vertical signal line 52-6 located between the ADC 451-6 and a position P1-6 where the pixel 51-6 and the vertical signal line 52-6 are electrically connected, and a portion of the vertical signal line 52-8 located between the ADC 451-6 and a position P1-8 where the pixel 51-8 and the vertical signal line 52-8 are electrically connected. The switch 453-4 also switches between connection and disconnection between a portion of the vertical signal line 52-6 located between the ADC 451-6 and a position P2-6 where the pixel 51-14 and the vertical signal line 52-6 are electrically connected, and a portion of the vertical signal line 52-8 located between the ADC 451-6 and a position P2-8 where the pixel 51-16 and the vertical signal line 52-8 are electrically connected.

[0049] Switches 453-1 to 453-4 are controlled by the drive control unit 43 under instructions from the body control unit 23. When source follower addition is to be performed, the body control unit 23 instructs the drive control unit 43 to turn switches 453-1 to 453-4 ON. On the other hand, when source follower addition is not to be performed, the body control unit 23 instructs the drive control unit 43 to turn switches 453-1 to 453-4 OFF.

[0050] When the drive control unit 43 turns on the switch 453-1, it operates either the ADC 451-1 connected to the vertical signal line 52-1 or the ADC 451-3 connected to the vertical signal line 52-3 (for example, the ADC 451-1) and does not operate the other (for example, the ADC 451-3). As a result, the pixel signal output to the vertical signal line 52-1 and the pixel signal output to the vertical signal line 52-3 are added together using a source follower, and the added signal is AD converted by the ADC 451-1.

[0051] Furthermore, when the drive control unit 43 turns on the switch 453-2, it operates either the ADC 451-2 connected to the vertical signal line 52-2 or the ADC 451-4 connected to the vertical signal line 52-4 (for example, the ADC 451-2) and does not operate the other (for example, the ADC 451-4). As a result, the pixel signal output to the vertical signal line 52-2 and the pixel signal output to the vertical signal line 52-4 are added together using a source follower, and the added signal is AD converted by the ADC 451-2.

[0052] Furthermore, when the drive control unit 43 turns on the switch 453-3, it operates either the ADC 451-5 connected to the vertical signal line 52-5 or the ADC 451-7 connected to the vertical signal line 52-7 (for example, the ADC 451-5) and does not operate the other (for example, the ADC 451-7). As a result, the pixel signal output to the vertical signal line 52-5 and the pixel signal output to the vertical signal line 52-7 are added together using a source follower, and the added signal is AD converted by the ADC 451-5.

[0053] Furthermore, when the drive control unit 43 turns on the switch 453-4, it operates either the ADC 451-6 connected to the vertical signal line 52-6 or the ADC 451-8 connected to the vertical signal line 52-8 (for example, the ADC 451-6) and does not operate the other (for example, the ADC 451-8). As a result, the pixel signal output to the vertical signal line 52-6 and the pixel signal output to the vertical signal line 52-8 are added together using a source follower, and the added signal is AD converted by the ADC 451-6.

[0054] In this embodiment, pixel signals are read out from pixels 51 in rows 1 to 16 in one horizontal synchronization signal period. Fig. 6 is a time chart showing the operation of the image sensor 21 when source follower addition is performed in this embodiment.

[0055] When performing source follower addition, switches 453-1 to 453-4 are always ON. In the example of Fig. 6, ADCs 451-3, 451-4, 451-7, and 451-8 are not used (not operated).

[0056] The horizontal synchronization signal is output at times t1, t3, and t5. Between times t1 and t3, pixel signals are read from the pixels 51 in the 1st to 16th rows, and after source follower addition, the sum signal is AD converted. Furthermore, between times t3 and t5, pixel signals are read from the pixels 51 in the 17th to 32nd rows, and after source follower addition, the sum signal is AD converted.

[0057] Specifically, at time t1, pixel signals are output from pixels 51-1 to 51-8 in the first to eighth rows to vertical signal lines 52-1 to 52-8, respectively, at the same timing. The pixel signals output from pixels 51-1 and 51-3 in the first and third rows are source-follower added, and the added signal is input to ADC 451-1. Between time t1 and time t2, ADC 451-1 performs AD conversion on the added signal (indicated by "1+3") obtained by source-follower adding the pixel signal from pixel 51-1 in the first row and the pixel signal from pixel 51-3 in the third row.

[0058] The pixel signals output from the pixels 51-2 and 51-4 in the second and fourth rows are source-follower added, and the added signal is input to the ADC 451-2. Between time t1 and time t2, the ADC 451-2 performs AD conversion on the added signal obtained by source-follower adding the pixel signal from the pixel 51-2 in the second row and the pixel signal from the pixel 51-4 in the fourth row (indicated by "2+4").

[0059] The pixel signals output from the pixels 51-5 and 51-7 on the fifth and seventh rows are source-follower added, and the added signal is input to the ADC 451-5. Between time t1 and time t2, the ADC 451-5 performs AD conversion on the added signal (indicated as "5+7") obtained by source-follower adding the pixel signal from the pixel 51-5 on the fifth row and the pixel signal from the pixel 51-7 on the seventh row.

[0060] The pixel signals output from the pixels 51-6 and 51-8 on the sixth and eighth rows are source-follower added, and the added signal is input to the ADC 451-6. Between time t1 and time t2, the ADC 451-6 performs AD conversion on the added signal (indicated by "6+8") obtained by source-follower adding the pixel signal from the pixel 51-6 on the sixth row and the pixel signal from the pixel 51-8 on the eighth row.

[0061] At time t2, pixel signals from pixels 51-9 to 51-16 on the 9th to 16th rows are output to vertical signal lines 52-1 to 52-8, respectively, at the same timing. The pixel signals output from pixels 51-9 and 51-11 on the 9th and 11th rows are source-follower added, and the added signal is input to ADC 451-1. Between time t2 and time t3, ADC 451-1 performs AD conversion on the added signal (indicated by "9+11") obtained by source-follower adding the pixel signal from pixel 51 on the 9th row and the pixel signal from pixel 51 on the 11th row. That is, ADC 451-1 performs time-division AD conversion of an added signal obtained by source-follower addition of the pixel signal from pixel 51-1 on the first row and the pixel signal from pixel 51-3 on the third row, and AD conversion of an added signal obtained by source-follower addition of the pixel signal from pixel 51-9 on the ninth row and the pixel signal from pixel 51-11 on the eleventh row, within one horizontal synchronization signal period (the period between time t1 and time t3).

[0062] The pixel signals output from the pixels 51-10 and 51-12 on the 10th and 12th rows are source-follower added, and the resulting sum signal is input to the ADC 451-2. Between time t2 and time t3, the ADC 451-2 AD-converts the sum signal obtained by source-follower adding the pixel signal from the pixel 51-10 on the 10th row and the pixel signal from the pixel 51-12 on the 12th row (indicated by "10+12"). That is, the ADC 451-2 performs AD conversion of the sum signal obtained by source-follower adding the pixel signal from the pixel 51-2 on the 2nd row and the pixel signal from the pixel 51-4 on the 4th row, and AD conversion of the sum signal obtained by source-follower adding the pixel signal from the pixel 51-10 on the 10th row and the pixel signal from the pixel 51-12 on the 12th row, in a time-division manner within one horizontal synchronization signal period (the period between time t1 and time t3).

[0063] The pixel signals output from pixels 51-13 and 51-15 on the 13th and 15th rows are source-follower added, and the resulting signal is input to the ADC 451-5. Between time t2 and time t3, the ADC 451-5 AD-converts the resulting signal obtained by source-follower adding the pixel signal from pixel 51-13 on the 13th row and the pixel signal from pixel 51-15 on the 15th row. That is, the ADC 451-5 performs AD conversion of the resulting signal obtained by source-follower adding the pixel signal from pixel 51-5 on the 5th row and the pixel signal from pixel 51-7 on the 7th row, and AD conversion of the resulting signal obtained by source-follower adding the pixel signal from pixel 51-13 on the 13th row and the pixel signal from pixel 51-15 on the 15th row, in a time-division manner within one horizontal synchronization signal period (the period between time t1 and time t3).

[0064] The pixel signals output from pixels 51-14 and 51-16 on the 14th and 16th rows are source-follower added, and the resulting signal is input to the ADC 451-6. Between time t2 and time t3, the ADC 451-6 performs AD conversion on the resulting signal obtained by source-follower adding the pixel signal from pixel 51-14 on the 14th row and the pixel signal from pixel 51-16 on the 16th row. That is, the ADC 451-6 performs AD conversion on the resulting signal obtained by source-follower adding the pixel signal from pixel 51-6 on the 6th row and the pixel signal from pixel 51-8 on the 8th row, and AD conversion on the resulting signal obtained by source-follower adding the pixel signal from pixel 51-14 on the 14th row and the pixel signal from pixel 51-16 on the 16th row, in a time-division manner within one horizontal synchronization signal period (the period between time t1 and time t3).

[0065] Next, between time t3 and time t5, pixel signals are read from the pixels 51 on the 17th to 32nd rows, and after source follower addition, AD conversion is performed. Specifically, at time t3, pixel signals are output from the pixels 51 on the 17th to 24th rows to the vertical signal lines 52-1 to 52-8, respectively, at the same timing. At time t4, pixel signals are output from the pixels 51 on the 25th to 32nd rows to the vertical signal lines 52-1 to 52-8, respectively, at the same timing. The processing performed from time t3 to time t5 is similar to the processing performed from time t1 to time t3, and therefore a detailed description thereof will be omitted. As a trigger for outputting pixel signals at times t2 and t4, the horizontal drive unit 44 or the drive control unit 43 may count a predetermined number of clock signals to generate and output a trigger signal.

[0066] In this way, by performing the AD conversion process in a time-division manner in one horizontal synchronization signal period, pixel signals can be read out from 16 rows of pixels 51 in one horizontal synchronization signal period, thereby increasing the frame rate of the image sensor 21.

[0067] As described above in detail, according to the first embodiment, the image sensor 21 includes a pixel 51-1 having a photoelectric conversion unit that photoelectrically converts incident light, a pixel 51-3 having a photoelectric conversion unit that photoelectrically converts incident light, a vertical signal line 52-1 that outputs a pixel signal based on charges generated in the photoelectric conversion unit of the pixel 51-1, and a vertical signal line 52-3 that outputs a pixel signal based on charges generated in the photoelectric conversion unit of the pixel 51-3. The image sensor 21 also includes an ADC 451-1 electrically connected to the vertical signal line 52-1 and converting an input pixel signal from an analog signal to a digital signal, and an ADC 451-3 electrically connected to the vertical signal line 52-3 and converting an input pixel signal from an analog signal to a digital signal. Furthermore, in order to add the pixel signal output to the vertical signal line 52-1 and the pixel signal output to the vertical signal line 52-3, the image sensor 21 includes a switch 453-1 that switches between connection and disconnection of a portion of the vertical signal line 52-1 located between the ADC 451-1 and a position P1-1 where the pixel 51-1 and the vertical signal line 52-1 are electrically connected, and a portion of the vertical signal line 52-3 located between the ADC 451-3 and a position P1-3 where the pixel 51-3 and the vertical signal line 52-3 are electrically connected. As a result, when performing source follower addition, turning on the switch 453-1 enables source follower addition of pixel signals from the pixels 51-1 and 51-3, which are connected to different vertical signal lines 52-1 and 52-3, respectively.

[0068] In this embodiment, the image sensor 21 includes a pixel 51-9 having a photoelectric conversion unit that photoelectrically converts incident light, and a pixel 51-11 having a photoelectric conversion unit that photoelectrically converts incident light. A pixel signal based on charges generated by the photoelectric conversion unit of the pixel 51-9 is output to a vertical signal line 52-1 at a timing different from that of the pixel signal from the pixel 51-1, and a pixel signal based on charges generated by the photoelectric conversion unit of the pixel 51-11 is output to a vertical signal line 52-3 at a timing different from that of the pixel signal from the pixel 51-3. When the vertical signal line 52-1 and the vertical signal line 52-3 are connected, for example, the ADC 451-1 of the ADC 451-1 and the ADC 451-3 performs, in a time-division manner, a process of converting into a digital signal an addition signal obtained by source-follower adding the pixel signal from the pixel 51-1 and the pixel signal from the pixel 51-3, and a process of converting into a digital signal an addition signal obtained by source-follower adding the pixel signal from the pixel 51-9 and the pixel signal from the pixel 51-11. This makes it possible to double the frame rate compared to the case where the AD conversion process is not performed in a time-division manner (when each ADC AD-converts the addition signal of pixel signals from two rows of pixels 51 during one horizontal synchronization signal period).

[0069] In the above embodiment, when performing source follower addition, the case has been described in which ADC 451-1 operates while ADC 451-3 does not operate. However, ADC 451-1 may not operate and ADC 451-3 may operate. By operating one of ADC 451-1 and ADC 451-3 and not operating the other, power consumption can be reduced. Furthermore, the ADC operated when performing source follower addition (when switch 453-1 is turned ON) may always be the same or may be changed, for example, at regular intervals. That is, in the image sensor 21, for example, it is possible to switch between a state in which ADC 451-1 operates and ADC 451-3 does not operate, and a state in which ADC 451-1 does not operate and ADC 451-3 operates. The same applies to other ADCs and other embodiments.

[0070] Note that, in the above embodiment, a case where source follower addition is performed has been described. However, when source follower addition is not performed, the body control unit 23 turns off the switches 453-1 to 453-4 and outputs a control signal to the drive control unit 43 to operate the ADCs 451-1 to 451-8. In this case, the vertical drive unit 42 outputs pixel signals from eight rows of pixels 51 at a time, under instructions from the drive control unit 43. As a result, pixel signals are output from the pixels 51-1 to 51-8 to the vertical signal lines 52-1 to 52-8 at the same timing, and pixel signals are output from the pixels 51-9 to 51-16 to the vertical signal lines 52-1 to 52-8 at the same timing. The pixel signals output to the vertical signal lines 52-1 to 52-8 are input to the ADCs 451-1 to 451-8, respectively, and are AD converted. Therefore, the image sensor 21 can switch between a state in which both the ADC 451-1 and the ADC 451-3 operate and a state in which one of the ADC 451-1 and the ADC 451-3 does not operate.

[0071] In the above embodiment, when the frame rate set in the camera body 2 is equal to or higher than a predetermined threshold, the set frame rate is realized by performing source follower addition. However, the image sensor 21 according to this embodiment can also realize the set frame rate by thinning and reading out pixel signals. In this case, the body control unit 23 outputs a control signal to the drive control unit 43 to turn off the switches 453-1 to 453-4 and operate the ADCs 451-1 to 451-8. For example, the drive control unit 43 first causes the pixels 51 in the first to eighth rows to output pixel signals, then causes the pixels 51 in the seventeenth to twenty-fourth rows to output pixel signals, and finally causes the pixels 51 in the thirty-third to fortieth rows to output pixel signals. In other words, the drive control unit 43 groups the pixels 51 in eight rows and causes the pixels 51 in every other group to output pixel signals. This allows the frame rate to be doubled compared to the frame rate when pixel signals are read out from all pixels. In addition, when the frame rate is equal to or higher than a predetermined threshold, whether to achieve that frame rate by source follower addition or by thinning out and reading out pixel signals may be determined, for example, based on the settings made by the user to the camera body 2, or may be determined by the body control unit 23 depending on, for example, the type of subject.

[0072] (Variation) In the first embodiment, AD conversion is performed by time-dividing one horizontal synchronization signal period into two, but AD conversion may also be performed by time-dividing one horizontal synchronization signal period into three. Here, a case where AD conversion is performed by time-dividing one horizontal synchronization signal period into three in the image sensor 21 will be described using the timing chart of FIG.

[0073] In the modified example, the switches 453-1 to 453-4 (see FIG. 5) of the imaging device 21 are always ON.

[0074] First, at time t41, pixel signals are output from the pixels 51 in the first to eighth rows to the vertical signal lines 52-1 to 52-8 at the same timing. The pixel signals output from the pixels 51 in the first and third rows are source-follower added, and the added signal is input to the ADC 451-1 and AD-converted (indicated by "1+3"). The pixel signals output from the pixels 51 in the second and fourth rows are source-follower added, and the added signal is input to the ADC 451-2 and AD-converted (indicated by "2+4").

[0075] The pixel signals output from the pixels 51 in the fifth and seventh rows are added together using a source follower, and the added signal is input to the ADC 451-5 and AD converted (indicated by "5+7"). The pixel signals output from the pixels 51 in the sixth and eighth rows are added together using a source follower, and the added signal is input to the ADC 451-6 and AD converted (indicated by "6+8").

[0076] At time t42, pixel signals are output from the pixels 51 on the 9th to 16th rows to the vertical signal lines 52-1 to 52-8 at the same timing. The pixel signals output from the pixels 51 on the 9th and 11th rows are source-follower added, and the added signal is input to the ADC 451-1 and AD-converted (indicated by "9+11"). The pixel signals output from the pixels 51 on the 10th and 12th rows are source-follower added, and the added signal is input to the ADC 451-2 and AD-converted (indicated by "10+12").

[0077] The pixel signals output from the pixels 51 in the 13th and 15th rows are added together using a source follower, and the added signal is input to the ADC 451-5 and AD converted (indicated by "13+15"). The pixel signals output from the pixels 51 in the 14th and 16th rows are added together using a source follower, and the added signal is input to the ADC 451-6 and AD converted (indicated by "14+16").

[0078] At time t43, pixel signals are output from the pixels 51 on the 17th to 24th rows to the vertical signal lines 52-1 to 52-8 at the same timing. The pixel signals output from the pixels 51 on the 17th and 19th rows are source-follower added, and the added signal is input to the ADC 451-1 and AD-converted (indicated by "17+19"). The pixel signals output from the pixels 51 on the 18th and 20th rows are source-follower added, and the added signal is input to the ADC 451-2 and AD-converted (indicated by "18+20").

[0079] The pixel signals output from the pixels 51 in the 21st and 23rd rows are added together using a source follower, and the added signal is input to the ADC 451-5 and AD converted (indicated by "21+23"). The pixel signals output from the pixels 51 in the 22nd and 24th rows are added together using a source follower, and the added signal is input to the ADC 451-6 and AD converted (indicated by "22+24").

[0080] In this way, ADCs 451-1, 451-2, 451-5, and 451-6 perform AD conversion by time-dividing one horizontal synchronization signal period into three. This allows pixel signals to be output from pixels 51 in 24 rows during one horizontal synchronization signal period from time t41 to time t44, thereby further increasing the frame rate of the image sensor 21.

[0081] Second Embodiment In the first embodiment, for example, the timing at which pixel signals are read from the pixels 51-1 to 51-8 in the first to eighth rows is different from the timing at which pixel signals are read from the pixels 51-9 to 51-16 in the ninth to sixteenth rows. In the second embodiment, the timing at which pixel signals are read from the pixels 51-1 to 51-8 in the first to eighth rows and the timing at which pixel signals are read from the pixels 51-1 to 51-16 in the ninth to sixteenth rows are the same.

[0082] 8 is a diagram showing the configuration of an image sensor 21A according to the second embodiment. The image sensor 21A includes switches SW1-1, SW1-2, SW1-3, SW1-4, SW1-5, SW1-6, SW1-7, and SW1-8, and switches SW2-1, SW2-2, SW2-3, SW2-4, SW2-5, SW2-6, SW2-7, and SW2-8.

[0083] A signal processing unit 45A according to the second embodiment includes ADCs 451-1A, 451-2A, 451-3A, 451-4A, 451-5A, 451-6A, 451-7A, and 451-8A, switches 453-1A, 453-2A, 453-3A, and 453-4A, ADCs 451-1B, 451-2B, 451-3B, 451-4B, 451-5B, 451-6B, 451-7B, and 451-8B, and switches 453-1B, 453-2B, 453-3B, and 453-4B. The signal processing unit 45A also includes a correlated double sampling unit (CDS), but this is not shown in the figure. This also applies to the following figures.

[0084] The ADCs 451-1A to 451-8A are electrically connected to one ends of the vertical signal lines 52-1 to 52-8, respectively, and the ADCs 451-1B to 451-8B are electrically connected to the other ends of the vertical signal lines 52-1 to 52-8, respectively.

[0085] The switch 453-1A switches between connection and disconnection a portion of the vertical signal line 52-1 located between the ADC 451-1A and a position P1-1 where the pixel 51-1 and the vertical signal line 52-1 are electrically connected, and a portion of the vertical signal line 52-3 located between the ADC 451-3A and a position P1-3 where the pixel 51-3 and the vertical signal line 52-3 are electrically connected. The switch 453-1A also switches between connection and disconnection a portion of the vertical signal line 52-1 located between the ADC 451-1A and a position P3-1 where the pixel 51-17 and the vertical signal line 52-1 are electrically connected, and a portion of the vertical signal line 52-3 located between the ADC 451-3A and a position P3-3 where the pixel 51-19 and the vertical signal line 52-3 are electrically connected.

[0086] The switch 453-2A switches between connection and disconnection a portion of the vertical signal line 52-2 located between the ADC 451-2A and a position P1-2 where the pixel 51-2 and the vertical signal line 52-2 are electrically connected, and a portion of the vertical signal line 52-4 located between the ADC 451-4A and a position P1-4 where the pixel 51-4 and the vertical signal line 52-4 are electrically connected. The switch 453-2A also switches between connection and disconnection a portion of the vertical signal line 52-2 located between the ADC 451-2A and a position P3-2 where the pixel 51-18 and the vertical signal line 52-2 are electrically connected, and a portion of the vertical signal line 52-4 located between the ADC 451-4A and a position P1-4 where the pixel 51-4 and the vertical signal line 52-4 are electrically connected.

[0087] The switch 453-3A switches between connection and disconnection a portion of the vertical signal line 52-5 located between the ADC 451-5A and a position P1-5 where the pixel 51-5 and the vertical signal line 52-5 are electrically connected, and a portion of the vertical signal line 52-7 located between the ADC 451-7A and a position P1-7 where the pixel 51-7 and the vertical signal line 52-7 are electrically connected. The switch 453-3A also switches between connection and disconnection a portion of the vertical signal line 52-5 located between the ADC 451-5A and a position P3-5 where the pixel 51-21 and the vertical signal line 52-5 are electrically connected, and a portion of the vertical signal line 52-7 located between the ADC 451-7A and a position P3-7 where the pixel 51-23 and the vertical signal line 52-7 are electrically connected.

[0088] The switch 453-4A switches between connection and disconnection a portion of the vertical signal line 52-6 located between the ADC 451-6A and a position P1-6 where the pixel 51-6 and the vertical signal line 52-6 are electrically connected, and a portion of the vertical signal line 52-8 located between the ADC 451-8A and a position P1-8 where the pixel 51-8 and the vertical signal line 52-8 are electrically connected. The switch 453-4A also switches between connection and disconnection a portion of the vertical signal line 52-6 located between the ADC 451-6A and a position P3-6 where the pixel 51-22 and the vertical signal line 52-6 are electrically connected, and a portion of the vertical signal line 52-8 located between the ADC 451-8A and a position P3-8 where the pixel 51-24 and the vertical signal line 52-8 are electrically connected.

[0089] The switch 453-1B switches between connection and disconnection a portion of the vertical signal line 52-1 located between the ADC 451-1B and a position P2-1 where the pixel 51-9 and the vertical signal line 52-1 are electrically connected, and a portion of the vertical signal line 52-3 located between the ADC 451-3B and a position P2-3 where the pixel 51-11 and the vertical signal line 52-3 are electrically connected. The switch 453-1B also switches between connection and disconnection a portion of the vertical signal line 52-1 located between the ADC 451-1B and a position P4-1 where the pixel 51-25 and the vertical signal line 52-1 are electrically connected, and a portion of the vertical signal line 52-3 located between the ADC 451-3B and a position P4-3 where the pixel 51-27 and the vertical signal line 52-3 are electrically connected.

[0090] The switch 453-2B switches between connection and disconnection a portion of the vertical signal line 52-2 located between the ADC 451-2B and a position P2-2 where the pixel 51-10 and the vertical signal line 52-2 are electrically connected, and a portion of the vertical signal line 52-4 located between the ADC 451-4B and a position P2-4 where the pixel 51-12 and the vertical signal line 52-4 are electrically connected. The switch 453-2B also switches between connection and disconnection a portion of the vertical signal line 52-2 located between the ADC 451-2B and a position P4-2 where the pixel 51-26 and the vertical signal line 52-2 are electrically connected, and a portion of the vertical signal line 52-4 located between the ADC 451-4B and a position P4-4 where the pixel 51-28 and the vertical signal line 52-4 are electrically connected.

[0091] The switch 453-3B switches between connection and disconnection a portion of the vertical signal line 52-5 located between the ADC 451-5B and a position P2-5 where the pixel 51-13 and the vertical signal line 52-5 are electrically connected, and a portion of the vertical signal line 52-7 located between the ADC 451-7B and a position P2-7 where the pixel 51-15 and the vertical signal line 52-7 are electrically connected. The switch 453-3B also switches between connection and disconnection a portion of the vertical signal line 52-5 located between the ADC 451-5B and a position P4-5 where the pixel 51-29 and the vertical signal line 52-5 are electrically connected, and a portion of the vertical signal line 52-7 located between the ADC 451-7B and a position P4-7 where the pixel 51-31 and the vertical signal line 52-7 are electrically connected.

[0092] The switch 453-4B switches between connection and disconnection a portion of the vertical signal line 52-6 located between the ADC 451-6B and a position P2-6 where the pixel 51-14 and the vertical signal line 52-6 are electrically connected, and a portion of the vertical signal line 52-8 located between the ADC 451-8B and a position P2-8 where the pixel 51-16 and the vertical signal line 52-8 are electrically connected. The switch 453-4B also switches between connection and disconnection a portion of the vertical signal line 52-6 located between the ADC 451-6B and a position P4-6 where the pixel 51-30 and the vertical signal line 52-6 are electrically connected, and a portion of the vertical signal line 52-8 located between the ADC 451-8B and a position P4-8 where the pixel 51-32 and the vertical signal line 52-8 are electrically connected.

[0093] Between positions P1-1 and P2-1, switch SW1-1 switches between connection and disconnection of the portion of vertical signal line 52-1 between position P1-1 and ADC 451-1A and the portion of vertical signal line 52-1 between position P2-1 and ADC 451-1B.

[0094] Between positions P1-2 and P2-2, switch SW1-2 switches between connection and disconnection of the portion of vertical signal line 52-2 between position P1-2 and ADC 451-2A and the portion of vertical signal line 52-2 between position P2-2 and ADC 451-2B.

[0095] Between positions P1-3 and P2-3, the switch SW1-3 switches between connection and disconnection of the portion of the vertical signal line 52-3 between position P1-3 and ADC 451-3A and the portion of the vertical signal line 52-3 between position P2-3 and ADC 451-3B.

[0096] Between positions P1-4 and P2-4, switch SW1-4 switches between connection and disconnection of the portion of vertical signal line 52-4 between position P1-4 and ADC 451-4A and the portion of vertical signal line 52-4 between position P2-4 and ADC 451-4B.

[0097] Between positions P1-5 and P2-5, switch SW1-5 switches between connection and disconnection of the portion of vertical signal line 52-5 between position P1-5 and ADC 451-5A and the portion of vertical signal line 52-5 between position P2-5 and ADC 451-5B.

[0098] Between positions P1-6 and P2-6, switch SW1-6 switches between connection and disconnection of the portion of vertical signal line 52-6 between position P1-6 and ADC 451-6A and the portion of vertical signal line 52-6 between position P2-6 and ADC 451-6B.

[0099] Between positions P1-7 and P2-7, the switch SW1-7 switches between connection and disconnection of the portion of the vertical signal line 52-7 between position P1-7 and ADC 451-7A and the portion of the vertical signal line 52-7 between position P2-7 and ADC 451-7B.

[0100] Between positions P1-8 and P2-8, switch SW1-8 switches between connection and disconnection of the portion of vertical signal line 52-8 between position P1-8 and ADC 451-8A and the portion of vertical signal line 52-8 between position P2-8 and ADC 451-8B.

[0101] Between positions P3-1 and P4-1, switch SW2-1 switches between connection and disconnection of the portion of vertical signal line 52-1 between position P3-1 and ADC 451-1A and the portion of vertical signal line 52-1 between position P4-1 and ADC 451-1B.

[0102] Between positions P3-2 and P4-2, switch SW2-2 switches between connection and disconnection of the portion of vertical signal line 52-2 between position P3-2 and ADC 451-2A and the portion of vertical signal line 52-2 between position P4-2 and ADC 451-2B.

[0103] Between positions P3-3 and P4-3, the switch SW2-3 switches between connection and disconnection of the portion of the vertical signal line 52-3 between position P3-3 and ADC 451-3A and the portion of the vertical signal line 52-3 between position P4-3 and ADC 451-3B.

[0104] Between positions P3-4 and P4-4, the switch SW2-4 switches between connection and disconnection of the portion of the vertical signal line 52-4 between position P3-4 and ADC 451-4A and the portion of the vertical signal line 52-4 between position P4-4 and ADC 451-4B.

[0105] Between positions P3-5 and P4-5, switch SW2-5 switches between connection and disconnection of the portion of vertical signal line 52-5 between position P3-5 and ADC 451-5A and the portion of vertical signal line 52-5 between position P4-5 and ADC 451-5B.

[0106] Between positions P3-6 and P4-6, the switch SW2-6 switches between connection and disconnection of the portion of the vertical signal line 52-6 between position P3-6 and ADC 451-6A and the portion of the vertical signal line 52-6 between position P4-6 and ADC 451-6B.

[0107] Between positions P3-7 and P4-7, the switch SW2-7 switches between connection and disconnection of the portion of the vertical signal line 52-7 between position P3-7 and ADC 451-7A and the portion of the vertical signal line 52-7 between position P4-7 and ADC 451-7B.

[0108] Between positions P3-8 and P4-8, switch SW2-8 switches between connection and disconnection of the portion of vertical signal line 52-8 between position P3-8 and ADC 451-8A and the portion of vertical signal line 52-8 between position P4-8 and ADC 451-8B.

[0109] The ON / OFF of the switches SW1-1 to SW1-8 and the switches SW2-1 to SW2-8 is controlled by the drive control unit 43 based on a control signal from the body control unit .

[0110] FIG. 9 is a timing chart illustrating the operation of the image sensor 21A according to the second embodiment when source follower addition is performed.

[0111] First, at time t11, pixels 51-1 to 51-16 in the 1st to 16th rows output pixel signals. At this time, drive control unit 43 turns on switches 453-1A to 453-4A and switches 453-1B to 453-4B. Also, drive control unit 43 turns off switches SW1-1 to SW1-8 and turns on switches SW2-1 to SW2-8. Furthermore, the drive control unit 43 operates, for example, ADCs 451-1A, 451-2A, 451-5A, and 451-6A and ADCs 451-1B, 451-2B, 451-5B, and 451-6B, and does not operate, ADCs 451-3A, 451-4A, 451-7A, and 451-8A and ADCs 451-3B, 451-4B, 451-7B, and 451-8B. In Fig. 9, the inoperable ADCs are indicated as "unused."

[0112] Because switches SW1-1 to SW1-8 are OFF and switches SW2-1 to SW2-8 are ON, pixel signals output from pixels 51-1 to 51-8 on the first to eighth rows are output to ADCs 451-1A to 451-8A, respectively. Meanwhile, pixel signals output from pixels 51-9 to 51-16 on the ninth to sixteenth rows are output to ADCs 451-1B to 451-8B, respectively.

[0113] Because the switch 453-1A is ON, the pixel signal output from the pixel 51-1 in the first row and the pixel signal output from the pixel 51-3 in the third row are source-follower added together, and the added signal is input to the ADC 451-1A and AD-converted (indicated by "1+3"). Because the switch 453-2A is ON, the pixel signal output from the pixel 51-2 in the second row and the pixel signal output from the pixel 51-4 in the fourth row are source-follower added together, and the added signal is input to the ADC 451-2A and AD-converted (indicated by "2+4"). Because the switch 435-3A is ON, the pixel signal output from the pixel 51-5 in the fifth row and the pixel signal output from the pixel 51-7 in the seventh row are source-follower added together, and the added signal is input to the ADC 451-5A and AD-converted (indicated by "5+7"). Because switch 453-4A is ON, the pixel signal output from pixel 51-6 on the 6th row and the pixel signal output from pixel 51-8 on the 8th row are source follower added, and the added signal is input to ADC 451-6A and AD converted (indicated by "6+8").

[0114] Also, because the switch 453-1B is ON, the pixel signal output from the pixel 51-9 on the 9th row and the pixel signal output from the pixel 51-11 on the 11th row are source-follower added together, and the sum signal is input to the ADC 451-1B and AD-converted (indicated by "9+11"). Because the switch 453-2B is ON, the pixel signal output from the pixel 51-10 on the 10th row and the pixel signal output from the pixel 51-12 on the 12th row are source-follower added together, and the sum signal is input to the ADC 451-2B and AD-converted (indicated by "10+12"). Because the switch 453-3B is ON, the pixel signal output from the pixel 51-13 on the 13th row and the pixel signal output from the pixel 51-15 on the 15th row are source-follower added together, and the sum signal is input to the ADC 451-5B and AD-converted (indicated by "13+15"). Because switch 453-4B is ON, the pixel signal output from pixel 51-14 on the 14th row and the pixel signal output from pixel 51-16 on the 16th row are source follower added, and the added signal is input to ADC 451-6B and AD converted (indicated by "14+16").

[0115] Next, at time t12, pixels 51-17 to 51-32 on the 17th to 32nd rows output pixel signals. At this time, drive control unit 43 turns on switches 453-1A to 453-4A and switches 453-1B to 453-4B. Also, drive control unit 43 turns on switches SW1-1 to SW1-8 and turns off switches SW2-1 to SW2-8. Furthermore, the drive control unit 43 sets, for example, ADCs 451-1A, 451-2A, 451-5A, 451-6A and ADCs 451-1B, 451-2B, 451-5B, 451-6B to operate, and ADCs 451-3A, 451-4A, 451-7A, 451-8A and ADCs 451-3B, 451-4B, 451-7B, 451-8B to an inoperable state.

[0116] Because switches SW1-1 to SW1-8 are ON and switches SW2-1 to SW2-8 are OFF, pixel signals output from pixels 51-17 to 51-24 on the 17th to 24th rows are output to ADCs 451-1A to 451-8A, respectively. Meanwhile, pixel signals output from pixels 51-25 to 51-32 on the 25th to 32nd rows are output to ADCs 451-1B to 451-8B, respectively.

[0117] Because the switch 453-1A is ON, the pixel signal output from the pixel 51-17 on the 17th row and the pixel signal output from the pixel 51-19 on the 19th row are source-follower added together, and the sum signal is input to the ADC 451-1A and AD-converted (indicated by "17+19"). Because the switch 453-2A is ON, the pixel signal output from the pixel 51-18 on the 18th row and the pixel signal output from the pixel 51-20 on the 20th row are source-follower added together, and the sum signal is input to the ADC 451-2A and AD-converted (indicated by "18+20"). Because the switch 453-3A is ON, the pixel signal output from the pixel 51-21 on the 21st row and the pixel signal output from the pixel 51-23 on the 23rd row are source-follower added together, and the sum signal is input to the ADC 451-5A and AD-converted (indicated by "21+23"). Because switch 453-4A is ON, the pixel signal output from pixel 51-22 on the 22nd row and the pixel signal output from pixel 51-24 on the 24th row are source follower added, and the added signal is input to ADC 451-6A and AD converted (indicated as "22+24").

[0118] Also, because the switch 453-1B is ON, the pixel signal output from the pixel 51-25 on the 25th row and the pixel signal output from the pixel 51-27 on the 27th row are source-follower added together, and the sum signal is input to the ADC 451-1B and AD-converted (indicated by "25+27"). Because the switch 453-2B is ON, the pixel signal output from the pixel 51-26 on the 26th row and the pixel signal output from the pixel 51-28 on the 28th row are source-follower added together, and the sum signal is input to the ADC 451-2B and AD-converted (indicated by "26+28"). Because the switch 453-3B is ON, the pixel signal output from the pixel 51-29 on the 29th row and the pixel signal output from the pixel 51-31 on the 31st row are source-follower added together, and the sum signal is input to the ADC 451-5B and AD-converted (indicated by "29+31"). Because switch 453-4B is ON, the pixel signal output from pixel 51-30 on the 30th row and the pixel signal output from pixel 51-32 on the 32nd row are source follower added, and the added signal is input to ADC 451-6B and AD converted (indicated by "30+32").

[0119] In this way, pixel signals can be output simultaneously from 16 rows of pixels (pixels 51-1 to 51-16 in the first to sixteenth rows, and pixels 51-17 to 51-32 in the seventeenth to thirty-second rows), which increases the speed at which pixel signals are read from the pixels 51 compared to when pixel signals are output simultaneously from eight rows at a time. This increases the frame rate of the image sensor 21A. Furthermore, each ADC can perform AD conversion on the sum signal using one horizontal synchronization signal period, improving the accuracy of AD conversion.

[0120] As described above in detail, according to the second embodiment, the image sensor 21A includes a pixel 51-1 including a photoelectric conversion unit that photoelectrically converts incident light, a pixel 51-3 including a photoelectric conversion unit that photoelectrically converts incident light, a vertical signal line 52-1 that outputs a pixel signal based on charges generated in the photoelectric conversion unit of the pixel 51-1, and a vertical signal line 52-3 that outputs a pixel signal based on charges generated in the photoelectric conversion unit of the pixel 51-3. The image sensor 21A also includes an ADC 451-1A electrically connected to one end of the vertical signal line 52-1 and configured to convert the input pixel signal from an analog signal to a digital signal, an ADC 451-3A electrically connected to one end of the vertical signal line 52-3 and configured to convert the input pixel signal from an analog signal to a digital signal, and a switch 453-1A configured to connect or disconnect a portion of the vertical signal line 52-1 between the ADC 451-1A and a position P1-1 at which the pixel 51-1 and the vertical signal line 52-1 are electrically connected, and a portion of the vertical signal line 52-3 between the ADC 451-3A and a position P1-3 at which the pixel 51-3 and the vertical signal line 52-3 are electrically connected, in order to add the pixel signal from the pixel 51-1 and the pixel signal from the pixel 51-3. The image sensor 21A also includes an ADC 451-1B electrically connected to the other end of the vertical signal line 52-1 and converting an input analog signal into a digital signal, an ADC 451-3B electrically connected to the other end of the vertical signal line 52-3 and converting an input analog signal into a digital signal, a pixel 51-9 electrically connected to the vertical signal line 52-1 between position P1-1 and the ADC 451-1B and including a photoelectric conversion unit that photoelectrically converts incident light, and a pixel 51-11 electrically connected to the vertical signal line 52-3 between position P1-3 and the ADC 451-3B and including a photoelectric conversion unit that photoelectrically converts incident light.The image sensor 21 also includes a switch 453-1B that switches between connection and disconnection between a portion of the vertical signal line 52-1 located between a position P2-1 where the pixel 51-9 and the vertical signal line 52-1 are electrically connected and the ADC 451-1B, and a portion of the vertical signal line 52-3 located between a position P2-3 where the pixel 51-11 and the vertical signal line 52-3 are electrically connected and the ADC 451-3B. and a switch SW1-3, between positions P1-3 and P2-3, that switches between connection and disconnection a portion of vertical signal line 52-3 that is between position P1-3 and ADC 451-1B and a portion of vertical signal line 52-3 that is between position P1-3 and ADC 451-1B and a portion of vertical signal line 52-3 that is between position P2-3 and ADC 451-3B. Thus, by turning on switches 453-1A and 453-1B and turning off switches SW1-1 and SW1-3, pixel signals from pixels 51-1 and 51-3 can be source-follower added, the added signal can be AD-converted by ADC 451-1A, and pixel signals from pixels 51-9 and 51-11 can be source-follower added, and the added signal can be AD-converted by ADC 451-1B. Therefore, pixel signals can be simultaneously read from pixels equal to twice the number of vertical signal lines provided for each pixel column, and added together using source followers.

[0121] Furthermore, in the second embodiment, the image sensor 21A includes a plurality of vertical signal lines 52-1 to 52-8, one end of which is connected to ADCs 451-1A to 451-8A and the other end of which is connected to ADCs 451-1B to 451-8B, respectively. A plurality of pixels 51 are connected to each of the plurality of vertical signal lines 52-1 to 52-8, and when pixel signals based on charges generated in the photoelectric conversion units of two of the plurality of pixels 51, a pixel 51-1 and a pixel 51-9, are output to the vertical signal line 52-1 at the same timing, the pixel 51-1, which is electrically closer to the ADC 451-1A, of the two pixels 51-1 and 51-9, is connected to the ADC 451-1A, and the two The pixel 51-1 has a switch SW1-1 that connects the pixel 51-9, which is electrically closer to the ADC 451-1B out of the two pixels 51-1 and 51-9, to the ADC 451-1B, and a switch SW1-3 that connects the pixel 51-3, which is electrically closer to the ADC 451-3A out of the two pixels 51-3 and 51-11, to the ADC 451-3A, and connects the pixel 51-11, which is electrically closer to the ADC 451-3B out of the two pixels 51-3 and 51-11, to the ADC 451-3B. Furthermore, when pixel signals based on charges generated in the photoelectric conversion units of two of the plurality of pixels 51 (e.g., pixels 51-1, 51-3, 51-9, and 51-11) are output to corresponding vertical signal lines (e.g., vertical signal lines 52-1 and 52-3) at the same timing in two or more of the plurality of vertical signal lines 52-1 to 52-8 (e.g., vertical signal lines 52-1 and 52-3), a switch 453-1A is provided which can select whether to add up the pixel signals output to ADC 451-1A, and a switch 453-1B is provided which can select whether to add up the pixel signals output to ADC 451-1B. As a result, by turning on switches 453-1A and 453-1B and turning off switches SW1-1 and SW1-3, pixel signals from pixels 51-1 and 51-3 can be source-follower added, the added signal can be AD-converted by ADC 451-1A, and pixel signals from pixels 51-9 and 51-11 can be source-follower added, and the added signal can be AD-converted by ADC 451-1B.Therefore, pixel signals can be simultaneously read from pixels equal to twice the number of vertical signal lines provided for each pixel column, and added together using source followers.

[0122] In the second embodiment, the operation of the image sensor 21A when source follower addition is performed has been described, but when source follower addition is not performed, the drive control unit 43 turns off switches 453-1A to 453-4A and switches 453-1B to 453-4B. By turning off switches SW1-1 to SW1-8 and turning on switches SW2-1 to SW2-8, the drive control unit 43 can output pixel signals of pixels 51-1 to 51-8 in the first to eighth rows to ADCs 451-1A to 451-8A, respectively, and output pixel signals of pixels 51-9 to 51-16 in the ninth to sixteenth rows to ADCs 451-1B to 451-8B, respectively, at the same timing. Moreover, by turning on switches SW1-1 to SW1-8 and turning off switches SW2-1 to SW2-8, the drive control unit 43 causes the pixel signals of pixels 51-17 to 51-24 on the 17th to 24th rows to be output to ADCs 451-1A to 451-8A, respectively, and the pixel signals of pixels 51-9 to 51-16 on the 9th to 16th rows to be output to ADCs 451-1B to 451-8B, respectively, at the same timing. In this way, pixel signals can be read out simultaneously from pixels 51 on 16 rows, thereby making it possible to increase the frame rate compared to when an ADC is connected to only one end of a vertical signal line.

[0123] Third Embodiment In the first embodiment, the pixel signals output from two pixels 51 are added together by source follower addition, but the pixel signals output from three or more pixels 51 may also be added together by source follower addition.

[0124] 10 is a diagram showing the configuration of an image sensor 21B according to the third embodiment. In the image sensor 21B, 12 vertical signal lines 52-1 to 52-12 are provided for each pixel column. A signal processing unit 45B includes ADCs 451-1 to 451-12 and switches 453-1 to 453-8. The ADCs 451-1 to 451-12 are connected to the vertical signal lines 52-1 to 52-12, respectively.

[0125] The switch 453-1 switches between connection and disconnection between the vertical signal line 52-1 and the vertical signal line 52-3. The switch 453-2 switches between connection and disconnection between the vertical signal line 52-2 and the vertical signal line 52-4. The switch 453-3 switches between connection and disconnection between the vertical signal line 52-3 and the vertical signal line 52-5. The switch 453-4 switches between connection and disconnection between the vertical signal line 52-4 and the vertical signal line 52-6. The switch 453-5 switches between connection and disconnection between the vertical signal line 52-7 and the vertical signal line 52-9. The switch 453-6 switches between connection and disconnection between the vertical signal line 52-8 and the vertical signal line 52-10. The switch 453-7 switches between connection and disconnection between the vertical signal line 52-9 and the vertical signal line 52-11. The switch 453-8 switches between connection and disconnection between the vertical signal line 52-10 and the vertical signal line 52-12.

[0126] FIG. 11 is a timing chart for explaining the operation of the image sensor 21B according to the third embodiment when source follower addition is performed.

[0127] The horizontal synchronization signal is output at time t21, time t23, and time t25. Between time t21 and time t23, pixel signals are read from the pixels 51 in the 1st to 24th rows, and are subjected to source follower addition and AD conversion.

[0128] When performing source follower addition, the drive control section 43 turns on the switches 453-1 to 453-8. In addition, in the example of Fig. 11, the ADCs 451-3 to 451-6 and 451-9 to 451-12 are not used.

[0129] Specifically, at time t21, pixel signals are output from pixels 51-1 to 51-12 in the first to twelfth rows to vertical signal lines 52-1 to 52-12, respectively, at the same timing. The pixel signals output from pixels 51-1, 51-3, and 51-5 in the first, third, and fifth rows are source-follower added, and the added signal is input to the ADC 451-1. Between time t21 and time t22, the ADC 451-1 performs AD conversion on the added signal of the pixel signal from pixel 51-1 in the first row, the pixel signal from pixel 51-3 in the third row, and the pixel signal from pixel 51-5 in the fifth row (indicated by "1+3+5").

[0130] The pixel signals output from pixels 51-2, 51-4, and 51-6 in the second, fourth, and sixth rows are source-follower added, and the added signal is input to the ADC 451-2. Between time t21 and time t22, the ADC 451-2 performs AD conversion on the added signal of the pixel signal from pixel 51-2 in the second row, the pixel signal from pixel 51-4 in the fourth row, and the pixel signal from pixel 51-6 in the sixth row (indicated by "2+4+6").

[0131] The pixel signals output from the pixels 51-7, 51-9, and 51-11 in the 7th, 9th, and 11th rows are source-follower added, and the added signal is input to the ADC 451-7. Between time t21 and time t22, the ADC 451-7 performs AD conversion on the added signal of the pixel signal from the pixel 51-7 in the 7th row, the pixel signal from the pixel 51-9 in the 9th row, and the pixel signal from the pixel 51-11 in the 11th row (indicated as "7+9+11").

[0132] The pixel signals output from pixels 51-8, 51-10, and 51-12 on the 8th, 10th, and 12th rows are source-follower added, and the added signal is input to the ADC 451-8. Between time t21 and time t22, the ADC 451-8 performs AD conversion on the added signal of the pixel signal from pixel 51-8 on the 8th row, the pixel signal from pixel 51-10 on the 10th row, and the pixel signal from pixel 51-12 on the 12th row (indicated as "8+10+12").

[0133] At time t22, pixel signals are output from pixels 51-13 to 51-24 on the 13th to 24th rows to vertical signal lines 52-1 to 52-12 at the same timing. The pixel signals output from pixels 51-13, 51-15, and 51-17 on the 13th, 15th, and 17th rows are source-follower added, and the added signal is input to the ADC 451-1. Between time t22 and time t23, the ADC 451-1 performs AD conversion on the added signal of the pixel signal from pixel 51-13 on the 13th row, the pixel signal from pixel 51-15 on the 15th row, and the pixel signal from pixel 51-17 on the 17th row (indicated as "13+15+17"). That is, ADC 451-1 performs AD conversion of the sum signal of pixel signals from pixels 51-1, 51-3, and 51-5 in the first, third, and fifth rows, and AD conversion of the sum signal of pixel signals from pixels 51-13, 51-15, and 51-17 in the thirteenth, fifteenth, and seventeenth rows in a time-division manner within one horizontal synchronization signal period (the period between time t21 and time t23).

[0134] The pixel signals output from the pixels 51-14, 51-16, and 51-18 on the 14th, 16th, and 18th rows are source-follower added, and the added signal is input to the ADC 451-2. Between time t22 and time t23, the ADC 451-2 performs AD conversion on the added signal of the pixel signals from the pixels 51-14, 51-16, and 51-18 on the 14th, 16th, and 18th rows (indicated as "14+16+18"). That is, ADC 451-2 performs AD conversion of the sum signal of pixel signals from pixels 51-2, 51-4, and 51-6 in the second, fourth, and sixth rows, and AD conversion of the sum signal of pixel signals from pixels 51-14, 51-16, and 51-18 in the fourteenth, sixteenth, and eighteenth rows in a time-division manner during one horizontal synchronization signal period (the period between time t21 and time t23).

[0135] The pixel signals output from the pixels 51-19, 51-21, and 51-23 on the 19th, 21st, and 23rd rows are source-follower added, and the added signal is input to the ADC 451-7. Between time t22 and time t23, the ADC 451-7 performs AD conversion on the added signal of the pixel signals from the pixels 51-19, 51-21, and 51-23 on the 19th, 21st, and 23rd rows (indicated as "19+21+23"). That is, ADC 451-7 performs AD conversion of the sum signal of pixel signals from pixels 51-7, 51-9, and 51-11 on the 7th, 9th, and 11th rows, and AD conversion of the sum signal of pixel signals from pixels 51-19, 51-21, and 51-23 on the 19th, 21st, and 23rd rows in a time-division manner within one horizontal synchronization signal period (the period between time t21 and time t23).

[0136] The pixel signals output from the pixels 51-20, 51-22, and 51-24 on the 20th, 22nd, and 24th rows are source-follower added, and the added signal is input to the ADC 451-8. Between time t22 and time t23, the ADC 451-8 performs AD conversion on the added signal of the pixel signals output from the pixels 51-20, 51-22, and 51-24 on the 20th, 22nd, and 24th rows (indicated as "20+22+24"). That is, ADC 451-8 performs time-division AD conversion of the sum signal of pixel signals from pixels 51-8, 51-10, and 51-12 on the 8th, 10th, and 12th rows, and the sum signal of pixel signals output from pixels 51-20, 51-22, and 51-24 on the 20th, 22nd, and 24th rows, during one horizontal synchronization signal period (the period between time t21 and time t23).

[0137] Then, during one horizontal synchronization signal period between time t23 and time t25, pixel signals are read out from pixels 51-25 to 51-48 on the 25th to 48th rows, and after source follower addition, AD conversion is performed. Specifically, at time t23, pixel signals are output from pixels 51-25 to 51-36 on the 25th to 36th rows to vertical signal lines 52-1 to 52-12, respectively, at the same timing. Also, at time t24, pixel signals are output from pixels 51-37 to 51-48 on the 37th to 48th rows to vertical signal lines 52-1 to 52-12, respectively, at the same timing. The processing performed from time t23 to time t25 is similar to the processing performed from time t21 to time t23, and therefore a detailed description thereof will be omitted.

[0138] In this way, by providing 12 vertical signal lines 52-1 to 52-12 for each pixel column, performing source follower addition of pixel signals output to three vertical signal lines, and performing AD conversion processing in a time-division manner in one horizontal synchronization signal period, it is possible to process pixel signals from pixels 51 in 24 rows in one horizontal synchronization signal period, thereby further increasing the frame rate of the image sensor 21B.

[0139] Fourth Embodiment In the second embodiment, pixel signals output from two pixels 51 are added together using source follower addition, but pixel signals output from three or more pixels 51 may also be added together using source follower addition.

[0140] 12 is a diagram showing the configuration of an image sensor 21C according to the fourth embodiment. In the image sensor 21C, 12 vertical signal lines 52-1 to 52-12 are provided for each pixel column. The image sensor 21C also includes switches SW1-1 to SW1-12 and switches SW2-1 to SW2-12. In the image sensor 21B, a signal processing unit 45C includes ADCs 451-1A to 451-12A, ADCs 451-1B to 451-12B, switches 453-1A to 453-8A, and switches 453-1B to 453-8B.

[0141] The ADCs 451-1A to 451-12A are electrically connected to one ends of the vertical signal lines 52-1 to 52-12, respectively, and the ADCs 451-1B to 451-12B are electrically connected to the other ends of the vertical signal lines 52-1 to 52-12, respectively.

[0142] The switch 453-1A switches between connection and disconnection a portion of the vertical signal line 52-1 located between the ADC 451-1A and a position P1-1 where the pixel 51-1 and the vertical signal line 52-1 are electrically connected, and a portion of the vertical signal line 52-3 located between the ADC 451-3A and a position P1-3 where the pixel 51-3 and the vertical signal line 52-3 are electrically connected. The switch 453-1A also switches between connection and disconnection a portion of the vertical signal line 52-1 located between the ADC 451-1A and a position P3-1 where the pixel 51-25 and the vertical signal line 52-1 are electrically connected, and a portion of the vertical signal line 52-3 located between the ADC 451-3A and a position P3-3 where the pixel 51-27 and the vertical signal line 52-3 are electrically connected.

[0143] The switch 453-2A switches between connection and disconnection a portion of the vertical signal line 52-2 located between the ADC 451-2A and a position P1-2 where the pixel 51-2 and the vertical signal line 52-2 are electrically connected, and a portion of the vertical signal line 52-4 located between the ADC 451-4A and a position P1-4 where the pixel 51-4 and the vertical signal line 52-4 are electrically connected. The switch 453-2A also switches between connection and disconnection a portion of the vertical signal line 52-2 located between the ADC 451-2A and a position P3-2 where the pixel 51-26 and the vertical signal line 52-2 are electrically connected, and a portion of the vertical signal line 52-4 located between the ADC 451-4A and a position P3-4 where the pixel 51-28 and the vertical signal line 52-4 are electrically connected.

[0144] The switch 453-3A switches between connection and disconnection a portion of the vertical signal line 52-3 located between the ADC 451-3A and a position P1-3 where the pixel 51-3 and the vertical signal line 52-3 are electrically connected, and a portion of the vertical signal line 52-5 located between the ADC 451-3A and a position P1-5 where the pixel 51-5 and the vertical signal line 52-5 are electrically connected, and the switch 453-3A also switches between connection and disconnection a portion of the vertical signal line 52-3 located between the ADC 451-3A and a position P3-3 where the pixel 51-27 and the vertical signal line 52-3 are electrically connected, and a portion of the vertical signal line 52-5 located between the ADC 451-5A and a position P3-5 where the pixel 51-29 and the vertical signal line 52-5 are electrically connected, and the switch 453-3A.

[0145] The switch 453-4A switches between connection and disconnection a portion of the vertical signal line 52-4 located between the ADC 451-4A and a position P1-4 where the pixel 51-4 and the vertical signal line 52-4 are electrically connected, and a portion of the vertical signal line 52-6 located between the ADC 451-4A and a position P1-6 where the pixel 51-6 and the vertical signal line 52-6 are electrically connected, and the ADC 451-6A. The switch 453-4A also switches between connection and disconnection a portion of the vertical signal line 52-4 located between the ADC 451-4A and a position P3-4 where the pixel 51-28 and the vertical signal line 52-4 are electrically connected, and a portion of the vertical signal line 52-6 located between the ADC 451-6A and a position P3-6 where the pixel 51-30 and the vertical signal line 52-6 are electrically connected.

[0146] The switch 453-5A switches between connection and disconnection a portion of the vertical signal line 52-7 located between the ADC 451-7A and a position P1-7 where the pixel 51-7 and the vertical signal line 52-7 are electrically connected, and a portion of the vertical signal line 52-9 located between the ADC 451-9A and a position P1-9 where the pixel 51-9 and the vertical signal line 52-9 are electrically connected. The switch 453-5A also switches between connection and disconnection a portion of the vertical signal line 52-7 located between the ADC 451-7A and a position P3-7 where the pixel 51-31 and the vertical signal line 52-7 are electrically connected, and a portion of the vertical signal line 52-9 located between the ADC 451-9A and a position P3-9 where the pixel 51-33 and the vertical signal line 52-9 are electrically connected.

[0147] The switch 453-6A switches between connection and disconnection a portion of the vertical signal line 52-8 located between the ADC 451-8A and a position P1-8 where the pixel 51-8 and the vertical signal line 52-8 are electrically connected, and a portion of the vertical signal line 52-10 located between the ADC 451-10A and a position P1-10 where the pixel 51-10 and the vertical signal line 52-10 are electrically connected. The switch 453-6A also switches between connection and disconnection a portion of the vertical signal line 52-8 located between the ADC 451-8A and a position P3-8 where the pixel 51-24 and the vertical signal line 52-8 are electrically connected, and a portion of the vertical signal line 52-10 located between the ADC 451-10A and a position P3-10 where the pixel 51-26 and the vertical signal line 52-10 are electrically connected.

[0148] The switch 453-7A switches between connection and disconnection a portion of the vertical signal line 52-7 located between the ADC 451-7A and a position P1-7 where the pixel 51-7 and the vertical signal line 52-7 are electrically connected, and a portion of the vertical signal line 52-9 located between the ADC 451-9A and a position P1-9 where the pixel 51-9 and the vertical signal line 52-9 are electrically connected. The switch 453-7A also switches between connection and disconnection a portion of the vertical signal line 52-7 located between the ADC 451-7A and a position P3-7 where the pixel 51-31 and the vertical signal line 52-7 are electrically connected, and a portion of the vertical signal line 52-9 located between the ADC 451-9A and a position P3-9 where the pixel 51-33 and the vertical signal line 52-9 are electrically connected.

[0149] The switch 453-8A switches between connection and disconnection a portion of the vertical signal line 52-10 located between the ADC 451-10A and a position P1-10 where the pixel 51-10 and the vertical signal line 52-10 are electrically connected, and a portion of the vertical signal line 52-12 located between the ADC 451-12A and a position P1-12 where the pixel 51-12 and the vertical signal line 52-12 are electrically connected. The switch 453-8A also switches between connection and disconnection a portion of the vertical signal line 52-10 located between the ADC 451-10A and a position P3-10 where the pixel 51-34 and the vertical signal line 52-10 are electrically connected, and a portion of the vertical signal line 52-12 located between the ADC 451-12A and a position P3-12 where the pixel 51-36 and the vertical signal line 52-12 are electrically connected.

[0150] The switch 453-1B switches between connection and disconnection a portion of the vertical signal line 52-1 located between the ADC 451-1B and a position P2-1 where the pixel 51-13 and the vertical signal line 52-1 are electrically connected, and a portion of the vertical signal line 52-3 located between the ADC 451-3B and a position P2-3 where the pixel 51-15 and the vertical signal line 52-3 are electrically connected. The switch 453-1B also switches between connection and disconnection a portion of the vertical signal line 52-1 located between the ADC 451-1B and a position P4-1 where the pixel 51-37 and the vertical signal line 52-1 are electrically connected, and a portion of the vertical signal line 52-3 located between the ADC 451-3B and a position P4-3 where the pixel 51-39 and the vertical signal line 52-3 are electrically connected.

[0151] The switch 453-2B switches between connection and disconnection a portion of the vertical signal line 52-2 located between the ADC 451-2B and a position P2-2 where the pixel 51-14 and the vertical signal line 52-2 are electrically connected, and a portion of the vertical signal line 52-4 located between the ADC 451-4B and a position P2-4 where the pixel 51-16 and the vertical signal line 52-4 are electrically connected, and the switch 453-2B also switches between connection and disconnection a portion of the vertical signal line 52-2 located between the ADC 451-2B and a position P4-2 where the pixel 51-38 and the vertical signal line 52-2 are electrically connected, and a portion of the vertical signal line 52-4 located between the ADC 451-4B and a position P4-4 where the pixel 51-40 and the vertical signal line 52-4 are electrically connected, and the switch 453-2B.

[0152] The switch 453-3B switches between connection and disconnection a portion of the vertical signal line 52-3 located between the ADC 451-3B and a position P2-3 where the pixel 51-15 and the vertical signal line 52-3 are electrically connected, and a portion of the vertical signal line 52-5 located between the ADC 451-5B and a position P2-5 where the pixel 51-17 and the vertical signal line 52-5 are electrically connected, and the switch 453-3B also switches between connection and disconnection a portion of the vertical signal line 52-3 located between the ADC 451-3B and a position P4-3 where the pixel 51-39 and the vertical signal line 52-3 are electrically connected, and the switch 453-3B, and a portion of the vertical signal line 52-5 located between the ADC 451-5B and a position P4-5 where the pixel 51-41 and the vertical signal line 52-5 are electrically connected, and the switch 453-3B.

[0153] The switch 453-4B switches between connection and disconnection a portion of the vertical signal line 52-4 located between the ADC 451-4B and a position P2-4 where the pixel 51-16 and the vertical signal line 52-4 are electrically connected, and a portion of the vertical signal line 52-6 located between the ADC 451-6B and a position P2-6 where the pixel 51-18 and the vertical signal line 52-6 are electrically connected. The switch 453-4B also switches between connection and disconnection a portion of the vertical signal line 52-4 located between the ADC 451-4B and a position P4-4 where the pixel 51-40 and the vertical signal line 52-4 are electrically connected, and a portion of the vertical signal line 52-6 located between the ADC 451-6B and a position P4-6 where the pixel 51-42 and the vertical signal line 52-6 are electrically connected.

[0154] The switch 453-5B switches between connection and disconnection a portion of the vertical signal line 52-7 located between the ADC 451-7B and a position P2-7 where the pixel 51-19 and the vertical signal line 52-7 are electrically connected, and a portion of the vertical signal line 52-9 located between the ADC 451-9A and a position P2-9 where the pixel 51-21 and the vertical signal line 52-9 are electrically connected. The switch 453-5B also switches between connection and disconnection a portion of the vertical signal line 52-7 located between the ADC 451-7B and a position P4-7 where the pixel 51-43 and the vertical signal line 52-7 are electrically connected, and a portion of the vertical signal line 52-9 located between the ADC 451-9B and a position P4-9 where the pixel 51-45 and the vertical signal line 52-9 are electrically connected.

[0155] The switch 453-6B switches between connection and disconnection a portion of the vertical signal line 52-8 located between the ADC 451-8B and a position P2-8 where the pixel 51-20 and the vertical signal line 52-8 are electrically connected, and a portion of the vertical signal line 52-10 located between the ADC 451-10B and a position P2-10 where the pixel 51-22 and the vertical signal line 52-10 are electrically connected. The switch 453-6B also switches between connection and disconnection a portion of the vertical signal line 52-8 located between the ADC 451-8B and a position P4-8 where the pixel 51-44 and the vertical signal line 52-8 are electrically connected, and a portion of the vertical signal line 52-10 located between the ADC 451-10B and a position P4-10 where the pixel 51-46 and the vertical signal line 52-10 are electrically connected.

[0156] The switch 453-7B switches between connection and disconnection of a portion of the vertical signal line 52-9 located between the ADC 451-9B and a position P2-9 where the pixel 51-21 and the vertical signal line 52-9 are electrically connected, and a portion of the vertical signal line 52-11 located between the ADC 451-11B and a position P2-11 where the pixel 51-23 and the vertical signal line 52-11 are electrically connected. The switch 453-7B also switches between connection and disconnection of a portion of the vertical signal line 52-9 located between the ADC 451-9B and a position P4-9 where the pixel 51-45 and the vertical signal line 52-9 are electrically connected, and a portion of the vertical signal line 52-11 located between the ADC 451-11B and a position P4-11 where the pixel 51-47 and the vertical signal line 52-11 are electrically connected.

[0157] The switch 453-8B switches between connection and disconnection of a portion of the vertical signal line 52-10 located between the ADC 451-10B and a position P2-10 where the pixel 51-22 and the vertical signal line 52-10 are electrically connected, and a portion of the vertical signal line 52-12 located between the ADC 451-12B and a position P2-12 where the pixel 51-24 and the vertical signal line 52-12 are electrically connected. The switch 453-8B also switches between connection and disconnection of a portion of the vertical signal line 52-10 located between the ADC 451-10B and a position P4-10 where the pixel 51-46 and the vertical signal line 52-10 are electrically connected, and a portion of the vertical signal line 52-12 located between the ADC 451-12B and a position P4-12 where the pixel 51-48 and the vertical signal line 52-12 are electrically connected.

[0158] The switch SW1-1 switches between connection and disconnection between a portion of the vertical signal line 52-1 between the position P1-1 and the ADC 451-1A and a portion of the vertical signal line 52-1 between the position P2-1 and the ADC 451-1B, between positions P1-1 and P2-1. The switch SW2-1 switches between connection and disconnection between a portion of the vertical signal line 52-1 between the position P3-1 and the ADC 451-1A and a portion of the vertical signal line 52-1 between the position P4-1 and the ADC 451-1B, between positions P3-1 and P4-1.

[0159] The switch SW1-2 switches between connection and disconnection between a portion of the vertical signal line 52-2 between position P1-2 and the ADC 451-2A and a portion of the vertical signal line 52-2 between position P2-2 and the ADC 451-2B, between positions P1-2 and P2-2. The switch SW2-2 switches between connection and disconnection between a portion of the vertical signal line 52-2 between position P3-2 and the ADC 451-2A and a portion of the vertical signal line 52-2 between position P4-2 and the ADC 451-2B, between positions P3-2 and P4-2.

[0160] The switch SW1-3 switches between connection and disconnection between a portion of the vertical signal line 52-3 between position P1-3 and the ADC 451-3A and a portion of the vertical signal line 52-3 between position P2-3 and the ADC 451-3B, between positions P1-3 and P2-3. The switch SW2-3 switches between connection and disconnection between a portion of the vertical signal line 52-3 between position P3-3 and the ADC 451-3A and a portion of the vertical signal line 52-3 between position P4-3 and the ADC 451-3B, between positions P3-3 and P4-3.

[0161] The switch SW1-4 switches between connection and disconnection between a portion of the vertical signal line 52-4 between position P1-4 and the ADC 451-4A and a portion of the vertical signal line 52-4 between position P2-4 and the ADC 451-4B, between positions P1-4 and P2-4. The switch SW2-4 switches between connection and disconnection between a portion of the vertical signal line 52-4 between position P3-4 and the ADC 451-4A and a portion of the vertical signal line 52-4 between position P4-4 and the ADC 451-4B, between positions P3-4 and P4-4.

[0162] The switch SW1-5 switches between connection and disconnection between a portion of the vertical signal line 52-5 between position P1-5 and the ADC 451-5A and a portion of the vertical signal line 52-5 between position P2-5 and the ADC 451-5B, between positions P1-5 and P2-5. The switch SW2-5 switches between connection and disconnection between a portion of the vertical signal line 52-5 between position P3-5 and the ADC 451-5A and a portion of the vertical signal line 52-5 between position P4-5 and the ADC 451-5B, between positions P3-5 and P4-5.

[0163] The switch SW1-6 switches between connection and disconnection between a portion of the vertical signal line 52-6 between position P1-6 and the ADC 451-6A and a portion of the vertical signal line 52-6 between position P2-6 and the ADC 451-6B, between positions P1-6 and P2-6. The switch SW2-6 switches between connection and disconnection between a portion of the vertical signal line 52-6 between position P3-6 and the ADC 451-6A and a portion of the vertical signal line 52-6 between position P4-6 and the ADC 451-6B, between positions P3-6 and P4-6.

[0164] The switch SW1-7 switches between connection and disconnection between a portion of the vertical signal line 52-7 between position P1-7 and the ADC 451-7A and a portion of the vertical signal line 52-7 between position P2-7 and the ADC 451-7B, between positions P1-7 and P2-7. The switch SW2-7 switches between connection and disconnection between a portion of the vertical signal line 52-7 between position P3-7 and the ADC 451-7A and a portion of the vertical signal line 52-7 between position P4-7 and the ADC 451-7B, between positions P3-7 and P4-7.

[0165] The switch SW1-8 switches between connection and disconnection between a portion of the vertical signal line 52-8 between position P1-8 and the ADC 451-8A and a portion of the vertical signal line 52-8 between position P2-8 and the ADC 451-8B, between positions P1-8 and P2-8. The switch SW2-8 switches between connection and disconnection between a portion of the vertical signal line 52-8 between position P3-8 and the ADC 451-8A and a portion of the vertical signal line 52-8 between position P4-8 and the ADC 451-8B, between positions P3-8 and P4-8.

[0166] The switch SW1-9 switches between connection and disconnection between a portion of the vertical signal line 52-9 between position P1-9 and the ADC 451-9A and a portion of the vertical signal line 52-9 between position P2-9 and the ADC 451-9B, between positions P1-9 and P2-9. The switch SW2-9 switches between connection and disconnection between a portion of the vertical signal line 52-9 between position P3-9 and the ADC 451-9A and a portion of the vertical signal line 52-9 between position P4-9 and the ADC 451-9B, between positions P3-9 and P4-9.

[0167] The switch SW1-10 switches between connection and disconnection between a portion of the vertical signal line 52-10 between position P1-10 and the ADC 451-10A and a portion of the vertical signal line 52-10 between position P2-10 and the ADC 451-10B, between positions P1-10 and P2-10. The switch SW2-10 switches between connection and disconnection between a portion of the vertical signal line 52-10 between position P3-10 and the ADC 451-10A and a portion of the vertical signal line 52-10 between position P4-10 and the ADC 451-10B, between positions P3-10 and P4-10.

[0168] The switch SW1-11 switches between connection and disconnection between a portion of the vertical signal line 52-11 between position P1-11 and the ADC 451-11A and a portion of the vertical signal line 52-11 between position P2-11 and the ADC 451-11B, between positions P1-11 and P2-11. The switch SW2-11 switches between connection and disconnection between a portion of the vertical signal line 52-11 between position P3-11 and the ADC 451-11A and a portion of the vertical signal line 52-11 between position P4-11 and the ADC 451-11B, between positions P3-11 and P4-11.

[0169] The switch SW1-12 switches between connection and disconnection between a portion of the vertical signal line 52-12 between position P1-12 and the ADC 451-12A and a portion of the vertical signal line 52-12 between position P2-12 and the ADC 451-12B, between positions P1-12 and P2-12. The switch SW2-12 switches between connection and disconnection between a portion of the vertical signal line 52-12 between position P3-12 and the ADC 451-12A and a portion of the vertical signal line 52-12 between position P4-12 and the ADC 451-12B, between positions P3-12 and P4-12.

[0170] FIG. 13 is a timing chart illustrating the operation of the image sensor 21C according to the fourth embodiment when source follower addition is performed.

[0171] First, at time t31, pixels 51-1 to 51-24 on the 1st to 24th rows output pixel signals. At this time, drive control unit 43 turns on switches 453-1A to 453-8A and switches 453-1B to 453-8B. Also, drive control unit 43 turns off switches SW1-1 to SW1-12 and turns on switches SW2-1 to SW2-12. Furthermore, the drive control unit 43 sets, for example, ADCs 451-1A, 451-2A, 451-7A, 451-8A and ADCs 451-1B, 451-2B, 451-7B, 451-8B to operate, and ADCs 451-3A to 451-6A, ADCs 451-9A to 451-12A, ADCs 451-3B to 451-6B, and ADCs 451-9B to 451-12B to an inoperable state.

[0172] Because switches SW1-1 to SW1-12 are OFF and switches SW2-1 to SW2-12 are ON, pixel signals output from pixels 51-1 to 51-12 on the 1st to 12th rows are output to ADCs 451-1A to 451-12A, respectively. Meanwhile, pixel signals output from pixels 51-13 to 51-24 on the 13th to 24th rows are output to ADCs 451-1B to 451-12B, respectively.

[0173] Because switches 453-1A and 453-3A are ON, pixel signals output from pixels 51-1, 51-3, and 51-5 in the first, third, and fifth rows are source-follower added, and the added signal is input to ADC 451-1A and AD-converted (indicated by "1+3+5"). Because switches 453-2A and 453-4A are ON, pixel signals output from pixels 51-2, 51-4, and 51-6 in the second, fourth, and sixth rows are source-follower added, and the added signal is input to ADC 451-2A and AD-converted (indicated by "2+4+6"). Because switches 453-5A and 453-7A are ON, pixel signals output from pixels 51-7, 51-9, and 51-11 in the 7th, 9th, and 11th rows are source-follower added, and the added signal is input to ADC 451-7A and AD-converted (indicated by "7+9+11"). Because switches 453-6A and 453-8A are ON, pixel signals output from pixels 51-8, 51-10, and 51-12 in the 8th, 10th, and 12th rows are source-follower added, and the added signal is input to ADC 451-8A and AD-converted (indicated by "8+10+12").

[0174] Furthermore, because the switches 453-1B and 453-3B are ON, the pixel signals output from the pixels 51-3, 51-15, and 51-17 in the 13th, 15th, and 17th rows are source-follower added, and the added signal is input to the ADC 451-1B and AD-converted (indicated by "13+15+17"). Because the switches 453-2B and 451-3B are ON, the pixel signals output from the pixels 51-14, 51-16, and 51-18 in the 14th, 16th, and 18th rows are source-follower added, and the added signal is input to the ADC 451-2B and AD-converted (indicated by "14+16+18"). Because the switches 453-5B and 453-7B are ON, the pixel signals output from the pixels 51-19, 51-21, and 51-23 in the 19th, 21st, and 23rd rows are source-follower added, and the added signal is input to the ADC 451-7B and AD-converted (indicated by "19+21+23"). Because the switches 453-6B and 453-8B are ON, the pixel signals output from the pixels 51-20, 51-22, and 51-24 in the 20th, 22nd, and 24th rows are source-follower added, and the added signal is input to the ADC 451-8B and AD-converted (indicated by "20+22+24").

[0175] Next, at time t32, pixel signals are output from pixels 51 on the 25th to 48th rows. At this time, drive control unit 43 turns on switches 453-1A to 453-8A and switches 453-1B to 453-8B. In addition, drive control unit 43 turns on switches SW1-1 to SW1-12 and turns off switches SW2-1 to SW2-12. Furthermore, the drive control unit 43 sets, for example, ADCs 451-1A, 451-2A, 451-7A, 451-8A and ADCs 451-1B, 451-2B, 451-7B, 451-8B to operate, and ADCs 451-3A to 451-6A, ADCs 451-9A to 451-12A, ADCs 451-3B to 451-6B, and ADCs 451-9B to 451-12B to an inoperable state.

[0176] Because switches SW1-1 to SW1-12 are ON and switches SW2-1 to SW2-12 are OFF, pixel signals output from pixels 51 on the 25th to 36th rows are output to ADCs 451-1A to 451-8A, respectively. On the other hand, pixel signals output from pixels 51 on the 37th to 48th rows are output to ADCs 451-1B to 451-8B, respectively.

[0177] The pixel signals output from pixels 51-25, 51-27, and 51-29 on the 25th, 27th, and 29th rows are added together using a source follower, and the resulting sum signal is input to an ADC 451-1A and AD converted (indicated as "25+27+29"). The pixel signals output from pixels 51-26, 51-28, and 51-30 on the 26th, 28th, and 30th rows are added together using a source follower, and the resulting sum signal is input to an ADC 451-2A and AD converted (indicated as "26+28+30"). The pixel signals output from pixels 51-31, 51-33, and 51-35 on the 31st, 33rd, and 35th rows are added together using a source follower, and the resulting sum signal is input to an ADC 451-7A and AD converted (indicated as "31+33+35"). The pixel signals output from pixels 51-32, 51-34, and 51-36 on the 32nd, 34th, and 36th rows are source-follower added, and the added signal is input to ADC 451-8A and AD-converted (shown as "32+34+36").

[0178] Furthermore, pixel signals output from pixels 51-37, 51-39, and 51-41 on the 37th, 39th, and 41st rows are added together using a source follower, and the resulting sum signal is input to ADC 451-1B and AD converted (shown as "37+39+41"). Pixel signals output from pixels 51-38, 51-40, and 51-42 on the 38th, 40th, and 42nd rows are added together using a source follower, and the resulting sum signal is input to ADC 451-2B and AD converted (shown as "38+40+42"). Pixel signals output from pixels 51-43, 51-45, and 51-47 on the 43rd, 45th, and 47th rows are added together using a source follower, and the resulting sum signal is input to ADC 451-7B and AD converted (shown as "43+45+47"). The pixel signals output from pixels 51-44, 51-46, and 51-48 on the 44th, 46th, and 48th rows are source-follower added, and the added signal is input to ADC 451-8B and AD-converted (shown as "44+46+48").

[0179] In this way, pixel signals can be output simultaneously from 24 rows of pixels 51, which increases the readout speed of pixel signals from the pixels 51 compared to when pixel signals are output simultaneously from 8 rows or 16 rows. As a result, the frame rate of the image sensor 21C can be increased. Furthermore, each ADC can perform AD conversion on the sum signal using one horizontal synchronization signal period, improving the accuracy of AD conversion.

[0180] The number of pixels to be subjected to source follower addition is not limited to 2 or 3, and may be 4 or more. In this case, the number of vertical signal lines for each pixel column and the arrangement of switches may be determined according to the number of pixels to be subjected to source follower addition.

[0181] The above-described embodiment is not limited to this, and various modifications can be made without departing from the spirit and scope of the invention. [Explanation of symbols]

[0182] 1 camera 23 Body control unit 51, 51-1 to 51-48 pixels 52-1~52-12 Vertical signal lines 451-1~451-12 ADC 451-1A~451-12A ADC 451-1B~451-12B ADC 453-1~453-8 Switches 453-1A~453-8A Switch 453-1A~453-8B Switches SW1-1 to SW1-12 switches SW2-1 to SW2-12 switches

Claims

1. a first photoelectric conversion unit that performs photoelectric conversion on incident light; a second photoelectric conversion unit that performs photoelectric conversion on incident light; a first signal line through which a first signal based on the charge generated by the first photoelectric conversion unit is output; a second signal line through which a second signal based on the charge generated by the second photoelectric conversion unit is output; a first A / D conversion unit electrically connected to the first signal line and configured to convert the input first signal from an analog signal to a digital signal; a second A / D conversion unit electrically connected to the second signal line and configured to convert the input second signal from an analog signal to a digital signal; a first switch that switches between connection and disconnection between a first portion of the first signal line located between the first A / D conversion unit and a first position where the first photoelectric conversion unit and the first signal line are electrically connected, and a first portion of the second signal line located between the second A / D conversion unit and a second position where the second photoelectric conversion unit and the second signal line are electrically connected, in order to add the first signal and the second signal; An imaging element comprising:

2. a plurality of photoelectric conversion units including the first photoelectric conversion unit and the second photoelectric conversion unit are arranged in a two-dimensional matrix; the first photoelectric conversion unit and the second photoelectric conversion unit are arranged in the same column and are not adjacent to each other in the column direction; The imaging device according to claim 1 .

3. a state in which both the first A / D conversion unit and the second A / D conversion unit are in operation and a state in which one of the first A / D conversion unit and the second A / D conversion unit is inoperable can be switched.

3. The imaging device according to claim 1.

4. In a state in which one of the first A / D conversion unit and the second A / D conversion unit is not operating, a state in which the first A / D conversion unit operates but the second A / D conversion unit is not operating, and a state in which the first A / D conversion unit does not operate but the second A / D conversion unit operates can be switched. The imaging device according to claim 3 .

5. a third photoelectric conversion unit that photoelectrically converts incident light; a fourth photoelectric conversion unit that performs photoelectric conversion on incident light; Equipped with a third signal based on the charge generated by the third photoelectric conversion unit is output to the first signal line at a timing different from that of the first signal; a fourth signal based on the charge generated by the fourth photoelectric conversion unit is output to the second signal line at a timing different from that of the second signal; when the first portion of the first signal line and the first portion of the second signal line are connected, the other of the first A / D conversion unit and the second A / D conversion unit performs, in a time-division manner, a process of converting a first sum signal obtained by adding the first signal and the second signal into a digital signal, and a process of converting a second sum signal obtained by adding the third signal and the fourth signal into a digital signal.

5. The imaging device according to claim 3.

6. the first A / D conversion unit is electrically connected to one end of the first signal line, the second A / D conversion unit is electrically connected to one end of the second signal line, a third A / D conversion unit electrically connected to the other end of the first signal line and configured to convert an input analog signal into a digital signal; a fourth A / D conversion unit electrically connected to the other end of the second signal line and configured to convert an input analog signal into a digital signal; a third photoelectric conversion unit electrically connected to the first signal line between the first position and the third A / D conversion unit, and configured to perform photoelectric conversion of incident light; a fourth photoelectric conversion unit electrically connected to the second signal line between the second position and the fourth A / D conversion unit, and performing photoelectric conversion on incident light; a second switch that switches between connection and disconnection between a second portion of the first signal line located between the third A / D conversion unit and a third position where the third photoelectric conversion unit and the first signal line are electrically connected, and a second portion of the second signal line located between the fourth A / D conversion unit and a fourth position where the fourth photoelectric conversion unit and the second signal line are electrically connected; a third switch that switches between connection and disconnection of the first portion of the first signal line and the second portion of the first signal line between the third position and the first position; a fourth switch that switches between connection and disconnection of the first portion of the second signal line and the second portion of the second signal line between the fourth position and the second position; The imaging device according to claim 1 , comprising:

7. a state in which both the third A / D conversion unit and the fourth A / D conversion unit are in operation and a state in which one of the third A / D conversion unit and the fourth A / D conversion unit is inoperable can be switched. The imaging device according to claim 6 .

8. In a state in which one of the third A / D conversion unit and the fourth A / D conversion unit is not operating, it is possible to switch between a state in which the third A / D conversion unit operates but the fourth A / D conversion unit is not operating, and a state in which the third A / D conversion unit is not operating but the fourth A / D conversion unit is operating. The imaging device according to claim 7 .

9. when the first switch connects the first portion of the first signal line and the first portion of the second signal line and the second switch connects the second portion of the first signal line and the second portion of the second signal line, the third switch does not connect the first portion of the first signal line and the second portion of the first signal line, and the fourth switch does not connect the first portion of the second signal line and the second portion of the second signal line; The imaging device according to claim 6 .

10. The imaging device according to any one of claims 1 to 9; a control unit that controls the first switch based on a control parameter related to a frame readout time; An imaging device comprising:

11. the control parameter is a frame rate; the control unit turns on the first switch to connect the first portion of the first signal line and the first portion of the second signal line when the frame rate is equal to or higher than a predetermined threshold. The imaging device according to claim 10.

12. When the frame rate is less than the predetermined threshold, the control unit turns off the first switch to disconnect the first portion of the first signal line from the first portion of the second signal line. The imaging device according to claim 11.

13. The imaging device according to any one of claims 6 to 9; a control unit that, when a frame rate is equal to or higher than a predetermined threshold, turns on the first switch to connect the first portion of the first signal line and the first portion of the second signal line, turns on the second switch to connect the second portion of the first signal line and the second portion of the second signal line, turns off the third switch to disconnect the first portion of the first signal line and the second portion of the first signal line, and turns off the fourth switch to disconnect the first portion of the second signal line and the second portion of the second signal line; An imaging device comprising:

14. when the frame rate is less than the predetermined threshold, the control unit turns off the first switch to disconnect the first portion of the first signal line and the second portion of the second signal line, turns off the second switch to disconnect the second portion of the first signal line and the second portion of the second signal line, turns off the third switch to disconnect the first portion of the first signal line and the second portion of the first signal line, and turns off the fourth switch to disconnect the first portion of the second signal line and the second portion of the second signal line. The imaging device according to claim 13.

15. each of the plurality of signal lines having one end connected to the first A / D conversion unit and the other end connected to the second A / D conversion unit; a plurality of photoelectric conversion units are connected to each of the plurality of signal lines; each of the plurality of signal lines includes a switch that connects one of the two photoelectric conversion units that is electrically closer to the first A / D conversion unit to the first A / D conversion unit when signals based on charges generated by two of the plurality of photoelectric conversion units are output to the signal line at the same timing, and connects one of the two photoelectric conversion units that is electrically closer to the second A / D conversion unit to the second A / D conversion unit; In the case where signals based on charges generated by two of the plurality of photoelectric conversion units are output to corresponding signal lines at the same timing, a first switching unit capable of switching whether or not to add the signals output to the first A / D conversion unit and a second switching unit capable of switching whether or not to add the signals output to the second A / D conversion unit are provided in two or more of the plurality of signal lines. Image sensor.

Images