Image sensor

Abstract

A technique for improving the focus detection accuracy of an image sensor is provided. [Solution] The device comprises a first transfer section that transfers charges accumulated in the first storage section to the first FD section, a second transfer section that transfers charges accumulated in the second storage section to the first FD section, a third transfer section that transfers charges accumulated in the third storage section to the second FD section, a fourth transfer section that transfers charges accumulated in the fourth storage section to the third FD section, a first connection section that connects the first storage section and the third storage section, a second connection section that connects the second storage section and the fourth storage section, a first discharge section that discharges charges transferred from the first storage section to the third storage section via the first connection section to a first supply section that is supplied with a predetermined voltage when charges are being transferred from the second storage section to the first FD section by the first transfer section, and a second discharge section that discharges charges transferred from the second storage section to the fourth storage section via the second connection section to a second supply section that is supplied with a predetermined voltage when charges are being transferred from the first storage section to the first FD section by the first transfer section.

Description

[Technical Field]

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

[0002] Focus detection techniques using focus detection pixels are known (for example, see Patent Document 1). There has been a demand for improved accuracy in focus detection. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2010-263568 Summary of the Invention

[0004] According to a first aspect, an imaging element includes a first photoelectric conversion unit that converts light into electric charges, a second photoelectric conversion unit that converts light into electric charges, a third photoelectric conversion unit that converts light into electric charges, a fourth photoelectric conversion unit that converts light into electric charges, a first accumulation unit that accumulates the electric charges converted by the first photoelectric conversion unit, a second accumulation unit that accumulates the electric charges converted by the second photoelectric conversion unit, a third accumulation unit that accumulates the electric charges converted by the third photoelectric conversion unit, a fourth accumulation unit that accumulates the electric charges converted by the fourth photoelectric conversion unit, a first transfer unit that transfers the electric charges accumulated in the first accumulation unit to a first floating diffusion unit, a second transfer unit that transfers the electric charges accumulated in the second accumulation unit to the first floating diffusion unit, a third transfer unit that transfers the electric charges accumulated in the third accumulation unit to the second floating diffusion unit, and the fourth transfer section that transfers the charge accumulated in the fourth accumulation section to the third floating diffusion section; a first connection section that electrically connects the first accumulation section and the third accumulation section; a second connection section that electrically connects the second accumulation section and the fourth accumulation section; a first discharge section that, when charge is being transferred from the second accumulation section to the first floating diffusion section by the second transfer section, discharges the charge transferred from the first accumulation section to the third accumulation section via the first connection section to a first supply section that is supplied with a predetermined voltage; and a second discharge section that, when charge is being transferred from the first accumulation section to the first floating diffusion section by the first transfer section, discharges the charge transferred from the second accumulation section to the fourth accumulation section via the second connection section to a second supply section that is supplied with a predetermined voltage. [Brief explanation of the drawings]

[0005] [Figure 1] 1 is a diagram illustrating an example of the configuration of an imaging device according to an embodiment; [Figure 2] FIG. 2 is a diagram illustrating a configuration example of an imaging element according to an embodiment. [Figure 3] FIG. 2 is a diagram illustrating an example of the configuration of a portion of an imaging element according to an embodiment. [Figure 4] 5A to 5C are diagrams illustrating an example of the operation of the imaging element according to the embodiment. [Figure 5]4 is a timing chart showing an example of the operation of the imaging element according to the embodiment. [Figure 6] FIG. 10 is a diagram illustrating an example of the configuration of a portion of an imaging element according to Modification 1. [Figure 7] 10 is a timing chart showing an example of the operation of the imaging element according to Modification 1. DETAILED DESCRIPTION OF THE INVENTION

[0006] (Embodiment) 1 is a diagram showing an example of the configuration of a camera 1, which is an example of an imaging device according to an embodiment. Camera 1 includes a photographing optical system (imaging optical system) 2, an image sensor 3, a control unit 4, a memory 5, a display unit 6, and an operation unit 7. The photographing optical system 2 has multiple lenses, including a focus lens (focus adjustment lens), and an aperture (aperture diaphragm), and forms an image of a subject on the image sensor 3. Note that the photographing optical system 2 may be detachable from the camera 1.

[0007] The imaging element 3 is an imaging element such as a CMOS image sensor or a CCD image sensor. The imaging element 3 receives a light beam that has passed through the photographing optical system 2 and captures an image of a subject formed by the photographing optical system 2. The imaging element 3 has a plurality of pixels, each of which has a photoelectric conversion unit, arranged two-dimensionally (in the row and column directions). The photoelectric conversion unit is composed of a photodiode (PD) and converts incident light into an electric charge. The imaging element 3 photoelectrically converts the received light to generate a signal and outputs the generated signal to the control unit 4.

[0008] The image sensor 3 has pixels (imaging pixels) that output signals used for image generation, and pixels (AF pixels) that output signals used for focus detection. The imaging pixels are arranged according to a Bayer array. The AF pixels are arranged to replace some of the imaging pixels, and are distributed over almost the entire image plane (imaging surface) of the image sensor 3. In the following description, when simply referring to pixels, this refers to either or both of the imaging pixels and the AF pixels.

[0009] The memory 5 is composed of a non-volatile storage medium, etc. The memory 5 stores image data, programs and data used to control each part of the camera 1, etc. The control unit 4 writes data to the memory 5 and reads data from the memory 5.

[0010] The display unit 6 is a liquid crystal display, an organic EL display, or the like. The display unit 6 displays a through image (live view image) of the subject, an image based on image data stored in the memory 5, an image showing a focus detection area (AF area) such as an AF frame, information related to shooting such as shutter speed and aperture value, a menu screen, and the like. The display unit 6 may include a touch panel and may also function as an input / output unit. The display unit (input / output unit) 6 may generate a signal based on an operation by the user and output it to the control unit 4.

[0011] The operation unit 7 includes members such as a release button, a power button (switch), an operation button, and switches for switching between various modes, and accepts operations on the camera 1. The operation unit 7 detects operations by the user and outputs a signal based on the operation to the control unit 4. The operation unit 7 may include a touch panel on the display unit 6.

[0012] The control unit 4 has a processor and memory, and controls each unit of the camera 1. The control unit 4 has devices such as a CPU, GPU, FPGA, ASIC, etc., and memories such as a ROM and RAM. The control unit 4 reads and executes programs stored in the memory. The control unit 4 can also be said to be a processing unit (information processing unit) that processes information based on the programs. The control unit 4 has an imaging control unit 4a, an image processing unit 4b, and a focus detection unit 4c.

[0013] The imaging control unit 4a supplies signals for controlling the imaging element 3 to the imaging element 3 and controls the operation of the imaging element 3. When taking a still image, taking a video, or displaying a through image of the subject on the display unit 6, the imaging control unit 4a causes the imaging element 3 to capture an image of the subject and output pixel signals. The imaging control unit 4a performs a so-called rolling shutter readout control, in which the imaging element 3 sequentially selects pixels row by row and reads signals from the selected pixels.

[0014] The imaging control unit 4a controls the image sensor 3 to separately read out signals from pixel rows in which AF pixels are arranged (hereinafter referred to as AF pixel rows) and from pixel rows in which AF pixels are not arranged (hereinafter referred to as imaging pixel rows).The imaging control unit 4a also sequentially selects pixel rows and reads out signals from each pixel, without separately reading out signals from AF pixel rows and imaging pixel rows.

[0015] For example, when displaying a through image on the display unit 6 or when capturing a moving image, the imaging control unit 4a separately reads out the signals of each pixel in the AF pixel row and the signals of each pixel in the imaging pixel row. When capturing a high-resolution still image, the imaging control unit 4a does not separately read out the signals of each pixel in the AF pixel row and the signals of each pixel in the imaging pixel row, but instead selects pixel rows sequentially and performs a process of reading out the signals.

[0016] The image processing unit 4b performs various image processing on signals output from the imaging pixels of the image sensor 3 to generate image data (still image data, moving image data) including signals from each pixel. The image processing unit 4b performs image processing such as color interpolation processing and gradation conversion processing. The image processing unit 4b may also generate image data using signals output from the AF pixels. The image processing unit 4b is an image data generation unit that generates image data.

[0017] The focus detection unit 4c performs focus detection processing required for automatic focusing (AF) of the photographic optical system 2. The focus detection unit 4c calculates the amount of defocus using a phase difference detection method, using signals output from a pair of AF pixels (AF pixel pair) of the image sensor 3. The focus detection unit 4c calculates the amount of image shift by performing a correlation operation between a first signal generated by capturing an image formed by a first light beam that has passed through a first region of the exit pupil of the photographic optical system 2, and a second signal generated by capturing an image formed by a second light beam that has passed through a second region of the exit pupil. The focus detection unit 4c converts this amount of image shift into a defocus amount using a predetermined conversion formula.

[0018] The focus detection unit 4c calculates the amount of movement of the focus lens to the in-focus position based on the calculated defocus amount. The focus lens is moved according to the amount of movement, and focus adjustment is performed. In this way, the control unit 4 controls the position of the focus lens so that the image of the subject formed by the photographing optical system 2 is focused (imaged) on the image sensor 3.

[0019] FIG. 2 is a diagram showing an example of the configuration of an image sensor according to an embodiment. The image sensor 3 has a pixel section (pixel region) 100 in which pixels are arranged two-dimensionally (in the row and column directions), a supply section 60, a readout control section 70, and multiple processing sections 80. Multiple image pixels 10 and AF pixels 20 (20a, 20b) are arranged in the pixel section 100 of the image sensor 3. In FIG. 2, the pixel in the upper left corner is image pixel 10(1,1) in the first row and first column, and the pixel in the lower right corner is image pixel 10(16,8) in the 16th row and eighth column, for a total of 128 pixels in 16 rows and 8 columns. Note that the number and arrangement of pixels arranged in the image sensor 3 are not limited to the example shown.

[0020] Each imaging pixel 10 is provided with one of three color filters 41 having different spectral characteristics of red (R), green (G), or blue (B). The imaging pixels 10 of the imaging element 3 include pixels (hereinafter referred to as R pixels) having color filters 41 with spectral characteristics that separate incident light in a first wavelength range (red (R) light), pixels (hereinafter referred to as G pixels) having color filters 41 with spectral characteristics that separate incident light in a second wavelength range (green (G) light), and pixels (hereinafter referred to as B pixels) having color filters 41 with spectral characteristics that separate incident light in a third wavelength range (blue (B) light). In FIG. 2, "R," "G," and "B" indicate the arrangement of R, G, and B color filters 41, respectively. The R, G, and B pixels are arranged according to a Bayer array.

[0021] The first AF pixel 20a and the second AF pixel 20b are arranged to replace some of the R, G, and B imaging pixels 10 arranged in a Bayer array as described above. The first and second AF pixels 20a and 20b are provided with color filters 41 having spectral characteristics that separate incident light in a second wavelength range (green (G) light). The color filters provided in the first and second AF pixels 20a and 20b may be color filters having spectral characteristics that separate incident light in a first wavelength range (red (R) light) or a third wavelength range (blue (B) light). The first and second AF pixels 20a and 20b may also have filters having spectral characteristics that separate incident light into first, second, and third wavelength ranges. Alternatively, the color filters 41 may not be provided in the first and second AF pixels 20a and 20b.

[0022] The first AF pixel 20a and the second AF pixel 20b each have a light-shielding portion 43 that blocks a portion of light incident on the photoelectric conversion unit. The first AF pixel 20a and the second AF pixel 20b have light-shielding portions 43 located at different positions. The light-shielding portions 43 of the first AF pixel 20a and the second AF pixel 20b are arranged so that light that has passed through different regions of the exit pupil of the photographing optical system 2 enters the photoelectric conversion unit. As a result, the photoelectric conversion unit of the first AF pixel 20a receives a light beam that has passed through a first region of the first and second regions of the exit pupil of the photographing optical system 2. The photoelectric conversion unit of the second AF pixel 20b receives a light beam that has passed through a second region of the first and second regions of the exit pupil of the photographing optical system 2.

[0023] 2, the image sensor 3 has a pixel group (first imaging pixel row) 401 in which G pixels 10g and B pixels 10b are arranged alternately in the left-right direction, i.e., in the row direction, and a pixel group (second imaging pixel row) 402 in which R pixels 10r and G pixels 10g are arranged alternately in the row direction. The image sensor 3 also has a pixel group (first AF pixel row) 403a in which G pixels 10g and first AF pixels 20a are arranged alternately in the row direction, and a pixel group (second AF pixel row) 403b in which G pixels 10g and second AF pixels 20b are arranged alternately in the row direction.

[0024] In the image sensor 3, a plurality of vertical signal lines 55 (first vertical signal line 55a and second vertical signal line 55b in FIG. 2) are provided for each of a plurality of pixels arranged in the horizontal direction (row direction). It can also be said that the first vertical signal line 55a and the second vertical signal line 55b are provided for each pixel column, which is a row of a plurality of pixels arranged in the vertical direction (column direction). A current source 56 (see FIG. 3) and a processing unit 80, which will be described later, are provided for each of the plurality of vertical signal lines 55.

[0025] The supply unit 60 supplies a predetermined voltage (potential) to each pixel under the control of the imaging control unit 4a of the camera 1. The supply unit 60 supplies a power supply voltage VDD to the imaging pixels 10 and the AF pixels 20 via a supply unit 65, which will be described later.

[0026] The readout control unit 70 is composed of multiple circuits, such as a timing generator, logic circuits (AND circuits, OR circuits, etc.), latch circuits, and buffers. The readout control unit 70 is controlled by the imaging control unit 4a and supplies signals, such as a signal TX, a signal RST, a signal SEL, and a signal FDSW (described later), to each pixel to control the operation of each pixel. The readout control unit 70 supplies a signal to the gate of each transistor in the pixel to turn the transistor on (connected state, conductive state, short-circuited state) or off (disconnected state, non-conductive state, open state, blocked state). The signal from each pixel is output to the first vertical signal line 55a or the second vertical signal line 55b connected to that pixel.

[0027] The processing unit 80 (first processing unit 80a, second processing unit 80b) is configured to include an analog / digital conversion unit (AD conversion unit). The processing unit 80 converts analog pixel signals input from each pixel via the vertical signal line 55 into digital signals. The processing unit 80 may also have an amplifier unit that amplifies the pixel signals input via the vertical signal line 55 by a predetermined gain (amplification factor). In this case, the processing unit 80 may convert the pixel signals amplified by the amplifier unit into digital signals.

[0028] The processing unit 80 outputs the pixel signals converted into digital signals to a signal processing unit (not shown). The signal processing unit performs signal processing such as correlated double sampling and signal amount correction on the input pixel signals, and then outputs the processed signals to the control unit 4 of the camera 1. The pixel signals output to the first vertical signal line 55a are input to the first processing unit 80a, where they are processed by the first processing unit 80a and then output to the control unit 4. The pixel signals output to the second vertical signal line 55b are input to the second processing unit 80b, where they are processed by the second processing unit 80b and then output to the control unit 4. Note that signal processing such as correlated double sampling on the pixel signals may be performed in the processing unit 80. In this case, the processing unit 80 may perform signal processing such as correlated double sampling on the pixel signals converted into digital signals, and then output the processed signals to the control unit 4.

[0029] 3 is a diagram illustrating an example of the configuration of a portion of an image sensor according to an embodiment. Of the plurality of pixels arranged in the column direction (vertical direction) and the row direction (horizontal direction) intersecting the column direction, FIG. 3 illustrates a portion of one pixel column of a plurality of pixel columns arranged in the column direction. The example illustrated in FIG. 3 illustrates, of the plurality of pixels shown in FIG. 2, a first AF pixel 20a (3,2) in the third row and second column, a G pixel 10g (4,2) in the fourth row and second column, a B pixel 10b (5,2) in the fifth row and second column, and a G pixel 10g (6,2) in the sixth row and second column. The configurations of the other pixel columns are similar to the configuration of the pixel columns in FIG. 3.

[0030] Each pixel (AF pixel 20, imaging pixel 10) includes a photoelectric conversion unit 11, a transfer unit 12, a storage unit 13, and a connection unit 14. Of two adjacent pixels in the column direction, one pixel (e.g., AF pixel 20) includes a photoelectric conversion unit 11a, a transfer unit 12a, a storage unit 13a, and a connection unit 14a, while the other pixel (e.g., imaging pixel 10) includes a photoelectric conversion unit 11b, a transfer unit 12b, a storage unit 13b, and a connection unit 14b. The connection units 14a and 14b can also be considered as switching units (switches) that switch between connection and disconnection. The photoelectric conversion units 11a and 11b are each photodiodes PD that convert incident light into electric charges and store the photoelectrically converted electric charges.

[0031] As shown by dashed line 45 in Fig. 3, the image sensor 3 is configured such that two adjacent pixels share a floating diffusion (FD) 15, a reset unit 16, an amplifier unit 17, a first selection unit 18, and a second selection unit 19. The supply unit 65 is a part (wiring, electrodes, etc.) of the image sensor 3 that supplies (applies) a power supply voltage VDD to the reset unit 16 and the amplifier unit 17. The supply unit 65 is supplied with the power supply voltage VDD from the supply unit 60 (see Fig. 2). The supply unit 65 may be a part of the supply unit 60.

[0032] The transfer unit 12a is composed of a transistor M1a controlled by a signal TX1. The transfer unit 12a is a connection unit 12a that electrically connects or disconnects the photoelectric conversion unit 11a to the storage unit 13a and the connection unit 14a. The transfer unit 12a can transfer charges photoelectrically converted by the photoelectric conversion unit 11a to the storage unit 13a and the FD15. The transfer unit 12b is composed of a transistor M1b that is controlled by a signal TX3. The transfer unit 12b is a connection unit 12b that electrically connects or disconnects the photoelectric conversion unit 11b to the storage unit 13b and the connection unit 14b. The transfer unit 12b can transfer charges photoelectrically converted by the photoelectric conversion unit 11b to the storage unit 13b and the FD15. The transistors M1a and M1b are each a transfer transistor.

[0033] The storage unit 13a is supplemented with capacitances such as the capacitance (parasitic capacitance) of the transistor connected to the storage unit 13a and the wiring capacitance. The storage unit 13a is a portion (region) that can accumulate (hold) the charge transferred to the storage unit 13a. The storage unit (holding unit) 13a can accumulate the charge generated in the photoelectric conversion unit 11. The storage unit 13b is supplemented with capacitances such as the capacitance of the transistor connected to the storage unit 13b and the wiring capacitance. The storage unit 13b is a portion (region) that can accumulate (hold) the charge transferred to the storage unit 13b. The storage unit (holding unit) 13b can accumulate the charge generated in the photoelectric conversion unit 11.

[0034] The connection unit 14a is composed of a transistor M2a controlled by a signal TX2. The connection unit 14a electrically connects or disconnects the transfer unit 12a and the storage unit 13a to or from the FD15. The connection unit 14a transfers the photoelectrically converted charges to the FD15. The connection unit 14b is composed of a transistor M2b controlled by a signal TX4. The connection unit 14b electrically connects or disconnects the transfer unit 12b and the storage unit 13b to or from the FD15. The connection unit 14b transfers the photoelectrically converted charges to the FD15. The capacitance C of the FD 15 is a capacitance that accumulates (holds) the charge transferred to the FD 15. The FD 15 is an accumulation unit 15, and accumulates the charge generated by the photoelectric conversion unit 11.

[0035] The amplifier 17 amplifies and outputs a signal based on the charges transferred from the first photoelectric conversion unit 11a and the second photoelectric conversion unit 11b. The amplifier 17 is composed of a transistor M4 whose gate (terminal) is connected to the FD 15. The drain (terminal) of the transistor M4 is connected to a supply unit 65 that supplies a power supply voltage VDD. The source (terminal) of the transistor M4 is connected to a first vertical signal line 55a via a first selection unit 18 and to a second vertical signal line 55b via a second selection unit 19. The transistor M4 is an amplifying transistor. The amplifier 17, the first selection unit 18, and the second selection unit 19 constitute an output unit that generates and outputs a signal based on the charges generated by the photoelectric conversion units.

[0036] The reset unit 16 is composed of a transistor M3 controlled by a signal RST and resets the charge accumulated by the FD15. The reset unit 16 is a connection unit 16 that electrically connects or disconnects the supply unit 65 and the FD15. The reset unit 16 connects the supply unit 65 and the FD15, thereby discharging the charge accumulated by the FD15 to the supply unit 65. The reset unit (discharge unit) 16 discharges the charge accumulated in the FD15 and resets the voltage of the FD15. The reset unit 16 can discharge the charge accumulated in the photoelectric conversion unit 11a via the connection unit 14a and the transfer unit 12a and reset the voltage of the photoelectric conversion unit 11a. The reset unit 16 can also discharge the charge accumulated in the photoelectric conversion unit 11b via the connection unit 14b and the transfer unit 12b and reset the voltage of the photoelectric conversion unit 11b. The transistor M3 is a reset transistor.

[0037] The first selection unit 18 is composed of a transistor M5 controlled by a signal SEL1, and electrically connects or disconnects the amplifier unit 17 and the first vertical signal line 55a. When the transistor M5 of the first selection unit 18 is in the on state, it outputs a signal from the amplifier unit 17 to the first vertical signal line 55a. The second selection unit 19 is composed of a transistor M6 controlled by a signal SEL2, and electrically connects or disconnects the amplifier unit 17 and the second vertical signal line 55b. When the transistor M6 of the second selection unit 19 is in the on state, it outputs a signal from the amplifier unit 17 to the second vertical signal line 55b. The transistors M5 and M6 are selection transistors.

[0038] The connection unit 25 is composed of a transistor M7 controlled by a signal FDSW. The connection unit 25 electrically connects or disconnects the storage unit 13 of one of the two pixels sharing the FD15, etc. to the storage unit 13 of a pixel other than the two pixels. It can also be said that the connection unit 25 electrically connects or disconnects between the transfer unit 12 and the connection unit 14 of one of the two pixels sharing the FD15, etc., and the transfer unit 12 and the connection unit 14 of the pixel other than the two pixels.

[0039] In the example shown in FIG. 3 , for example, a connection portion 25 (connection portion 25B) is provided that can electrically connect the storage portion 13b of the G pixel 10g(4,2) of the first AF pixel 20a(3,2) and the G pixel 10g(4,2) to the storage portion 13a of the B pixel 10b(5,2). Alternatively, a connection portion 25 that can electrically connect the storage portion 13b of the G pixel 10g(4,2) to the storage portion 13b of the G pixel 10g(6,2) may be provided. Alternatively, the connection portion 25 may be configured to electrically connect the storage portion 13a of the first AF pixel 20a(3,2) to the storage portion 13a of the B pixel 10b(5,2) (or the storage portion 13b of the G pixel 10g(6,2)). The connection portion 25 does not need to be provided between multiple pixels that do not include an AF pixel 20. The connection unit 25 can also be said to be a switching unit that switches between connection and disconnection.

[0040] The first current source 56a is connected to each pixel via the first vertical signal line 55a. The first current source 56a generates a current for reading out a signal from the pixel and supplies the generated current to the first vertical signal line 55a and the amplifier unit 17 and first selection unit 18 of each pixel. The second current source 56b is connected to each pixel via the second vertical signal line 55b. The second current source 56b generates a current for reading out a signal from the pixel and supplies the generated current to the second vertical signal line 55b and the amplifier unit 17 and second selection unit 19 of each pixel.

[0041] The pixel sequentially outputs a signal (dark signal) when the voltage of the FD 15 is reset and a signal (photoelectric conversion signal) corresponding to the charge transferred from the photoelectric conversion unit 11 to the FD 15 to the first vertical signal line 55a or the second vertical signal line 55b. The photoelectric conversion signal is an analog signal generated based on the charge photoelectrically converted by the photoelectric conversion unit 11. The dark signal is an analog signal indicating a reference level for the photoelectric conversion signal and is used to correct the photoelectric conversion signal. The dark signal can also be said to be a signal used to remove noise contained in the photoelectric conversion signal.

[0042] The signals output from the imaging pixels 10 are subjected to signal processing by the processing unit 80 and then output to the control unit 4 of the camera 1. The signals output from the first AF pixel 20a and the second AF pixel 20b are subjected to signal processing by the processing unit 80 and then output to the control unit 4 as a pair of signals (first and second signals).

[0043] In this embodiment, the imaging control unit 4a performs reading control using a rolling shutter method. The imaging pixel rows and AF pixel rows of the image sensor 3 are sequentially selected by the read control unit 70. The image sensor 3 performs a reset operation to discharge charges accumulated in the pixels and a read operation to read signals based on the charges accumulated in the pixels from the pixels (read operation) while scanning, for example, one or more rows at a time from the top row to the bottom row. The imaging control unit 4a controls the read control unit 70 to perform a first read process in which all pixel rows are sequentially selected and signals from each pixel are read, and a second read process in which signals from each pixel in the AF pixel rows and signals from each pixel in the imaging pixel rows are read separately.

[0044] When the imaging control unit 4a instructs the first readout process, the readout control unit 70 sequentially selects multiple pixel rows and causes each pixel to output a signal. In FIG. 2, the readout control unit 70 sequentially selects pixel rows in units of one or two rows, starting from the first row to the sixteenth row. The readout control unit 70 causes each pixel in the selected pixel row to output a signal to the vertical signal line 55. The signals read out from each pixel are subjected to signal processing by the processing unit 80 and then output to the control unit 4.

[0045] When the imaging control unit 4a instructs the second readout process, the readout control unit 70 separately reads out signals from each pixel in the AF pixel row and signals from each pixel in the imaging pixel row. When reading out signals from the AF pixel rows (first AF pixel row 403a, second AF pixel row 403b), the readout control unit 70 sequentially selects the multiple AF pixel rows of the image sensor 3 from the top row to the bottom row and reads out signals from each pixel. When reading out signals from the imaging pixel rows (first imaging pixel row 401, second imaging pixel row 402), the readout control unit 70 sequentially selects the multiple imaging pixel rows of the image sensor 3 from the top row to the bottom row and reads out signals from each pixel.

[0046] In the second readout process, signals from each pixel in the AF pixel row are read out separately from signals from each pixel in the imaging pixel row, so signals used for focus detection can be obtained efficiently and the burden of signal processing for AF can be reduced. When the second readout process is instructed, the readout control unit 70 may read signals from each pixel in the AF pixel row before reading signals from the imaging pixel row. In this case, the first and second signals of the AF pixel pair can be read out quickly, thereby shortening the time required for focus adjustment. Furthermore, the readout control unit 70 may read signals from each pixel in the imaging pixel row before reading signals from the AF pixel row.

[0047] 4 is a diagram showing an example of operation of the image sensor according to the embodiment, illustrating an example of operation when performing a second readout process to read out pixel signals. The vertical axis indicates pixel rows, and the horizontal axis indicates the timing (time t) at which the reset operation and readout operation of each pixel row are performed. FIG. 4 schematically illustrates the transition of pixel rows at which the reset operation and readout operation are performed.

[0048] As shown in Fig. 4, the readout control unit 70 performs reset operations and readout operations on the imaging pixel rows, and also performs reset operations and readout operations on the AF pixel rows. In this embodiment, the number of AF pixel rows is smaller than the number of imaging pixel rows, as schematically shown in Fig. 2. In the example shown in Fig. 4, the total number of AF pixel rows on which reset operations and readout operations are performed is smaller than the total number of imaging pixel rows on which reset operations and readout operations are performed, and the time required for scanning the AF pixel rows is shorter than that for scanning the imaging pixel rows.

[0049] 4, within dotted-line frame G1, there are cases where the readout operation of an imaging pixel row and the reset operation of an AF pixel row adjacent to that imaging pixel row are performed simultaneously. Also, within dotted-line frame G2, there are cases where the readout operation of an AF pixel row and the reset operation of an imaging pixel row adjacent to that AF pixel row are performed simultaneously.

[0050] During the period within the dotted-line frame G1, when the readout control unit 70 discharges charges accumulated in pixels in an AF pixel row adjacent to the imaging pixel row for which a readout operation is being performed, the readout control unit 70 turns off the connection units 14 of each pixel in that AF pixel row and turns on the transfer units 12 of each pixel in that AF pixel row and the connection units 25 connected to those transfer units 12. The readout control unit 70 also turns on the connection units 14 and reset units 16 of the adjacent pixel row connected to those connection units 25. The photoelectric conversion units 11 of the pixels in the AF pixel row adjacent to the imaging pixel row for which a readout operation is being performed are electrically connected to the supply unit 65 via the transfer units 12, connection units 25, connection units 14, and reset units 16. As a result, the charges accumulated in the photoelectric conversion units 11 of each pixel in the AF pixel row are discharged to the supply unit 65, and the voltage of the photoelectric conversion units 11 is reset.

[0051] In this way, the readout control unit 70 controls the pixels in the imaging pixel row to output signals based on the charges accumulated in the FD 15, and also controls the photoelectric conversion units 11 of the pixels in the AF pixel row to be electrically connected to the supply unit 65 via the connection units 25, etc. By controlling the connection units 25, the image sensor 3 can discharge the charges accumulated in the pixels in the AF pixel row adjacent to the imaging pixel row, even while a readout operation for that imaging pixel row is being performed.

[0052] During the period within the dotted-line frame G2, when the readout control unit 70 discharges charges accumulated in pixels in an imaging pixel row adjacent to the AF pixel row for which a readout operation is being performed, the readout control unit 70 turns off the connection units 14 of each pixel in that imaging pixel row and turns on the transfer units 12 of each pixel in that imaging pixel row and the connection units 25 connected to those transfer units 12. The readout control unit 70 also turns on the connection units 14 and reset units 16 of the adjacent pixel row connected to those connection units 25. The photoelectric conversion units 11 of the pixels in the imaging pixel row adjacent to the AF pixel row for which a readout operation is being performed are electrically connected to the supply unit 65 via the connection units 25, etc. As a result, the charges accumulated in the photoelectric conversion units 11 of each pixel in the imaging pixel row are discharged to the supply unit 65, and the voltage of the photoelectric conversion units 11 is reset.

[0053] In this way, the readout control unit 70 controls the pixels in the AF pixel row to output signals based on the charges accumulated in the FD 15, and also controls the photoelectric conversion units 11 of the pixels in the imaging pixel row to be electrically connected to the supply unit 65 via the connection units 25, etc. By controlling the connection units 25, the image sensor 3 can discharge the charges accumulated in the pixels in the imaging pixel row adjacent to the AF pixel row, even when a readout operation for that AF pixel row is being performed.

[0054] In the present embodiment, even if the timing of the readout operation of one pixel and the timing of the reset operation of the other pixel among adjacent pixels that share the FD 15 are simultaneous, it is possible to suppress degradation of the pixel signal quality. Below, the ability to suppress degradation of the pixel signal quality will be described in comparison with a comparative example.

[0055] The comparative example is a case where the image sensor 3 in FIG. 3 does not have the connection unit 25. In the comparative example, when discharging charges accumulated in the photoelectric conversion unit 11a (or 11b), the charges need to be discharged to the supply unit 65 via the transfer unit 12a (or 12b), the connection unit 14a (or 14b), the FD 15, and the reset unit 16. When reading out a photoelectric conversion signal, the charges photoelectrically converted by the photoelectric conversion unit 11b (or 11a) are transferred to the FD 15 via the transfer unit 12b (or 12a). For this reason, if a reset operation of one of two adjacent pixels sharing the FD 15 and a readout operation of the other pixel are simultaneously performed, the charges generated in the photoelectric conversion units 11a and 11b may be mixed together, or the charges transferred from the photoelectric conversion unit 11 of the pixel to be read out to the FD 15 may be discharged to the supply unit 65. In other words, a collision occurs between the read operation and the reset operation. In this case, it becomes impossible to properly read out a signal corresponding to the charge photoelectrically converted by the photoelectric conversion unit 11 of the pixel to be read out.

[0056] In this embodiment, when a readout operation is being performed on one of two adjacent pixels, the readout control unit 70 controls the connection unit 25 as described above, thereby discharging the charge from the photoelectric conversion unit 11 of the other pixel without going through the FD 15 of the pixel on which the readout operation is being performed. The reset operation is performed via a path separate from the path used to read out the pixel signal. This allows the image sensor 3 to avoid collisions between the readout operation and the reset operation.

[0057] In this way, the image sensor 3 according to this embodiment can appropriately read out signals corresponding to charges photoelectrically converted by the photoelectric conversion units 11 of the pixels to be read out. This makes it possible to prevent a decrease in the quality of the signals from each pixel in the imaging pixel row, thereby making it possible to prevent a decrease in the quality of the image generated using the pixel signals. Furthermore, this makes it possible to prevent a decrease in the quality of the signals from each pixel in the AF pixel row, thereby making it possible to prevent a decrease in the accuracy of focus detection using pixel signals.

[0058] Fig. 5 is a timing chart showing an example of operation of the imaging element according to the embodiment. An example of operation of the imaging element 3 shown in Fig. 3 will be described with reference to this flowchart. In the timing chart shown in Fig. 5, the vertical axis represents the voltage level of the signal, and the horizontal axis represents time. In Fig. 5, transistors receiving a high-level (e.g., power supply voltage VDD) control signal (signal RST, signal TX, signal SEL, signal FDSW) are turned on, and transistors receiving a low-level (e.g., ground voltage) control signal are turned off.

[0059] At time t1 shown in FIG. 5, the signal RST <0> The signal RST goes high. <0> When the signal TX1 goes high, the transistor M3 of the reset unit 16 shared by the first AF pixel 20a(3,2) in the third row and the G pixel 10g(4,2) in the fourth row is turned on. <0> and signal TX2 <0> When the signal RST goes high, the transistor M1a of the transfer unit 12a and the transistor M2a of the connection unit 14a are turned on. <0> and signal TX1 <0> and signal TX2 <0> are both at a high level, the supply unit 65, the FD 15, the storage unit 13a, and the photoelectric conversion unit 11a are electrically connected, whereby the charges in the FD 15, the storage unit 13a, and the photoelectric conversion unit 11a are discharged, and the voltages of the FD 15, the storage unit 13a, and the photoelectric conversion unit 11a are reset.

[0060] At time t2, the signal RST <0> becomes high level, the charge of the FD15 shared by the first AF pixel 20a(3,2) and the G pixel 10g(4,2) is reset, and the voltage of the FD15 becomes the reset voltage. <0> The signal SEL1 goes high. <0> When the signal VREF1 goes high, the transistor M5 of the first selection unit 18 shared by the first AF pixel 20a(3,2) and the G pixel 10g(4,2) is turned on. As a result, a signal based on the reset voltage of the first AF pixel 20a(3,2), that is, a signal obtained after the charge of the FD15 of the first AF pixel 20a(3,2) has been reset, is output to the first vertical signal line 55a by the amplifier unit 17 and the first selection unit 18. The signal based on the reset voltage is input as a dark signal (reset signal) to the first processing unit 80a via the first vertical signal line 55a and converted into a digital signal.

[0061] At time t2, the signal RST <1> The signal RST goes high. <1> When the signal TX1 goes high, the transistor M3 of the reset unit 16 shared by the B pixel 10b(5,2) in the fifth row and the G pixel 10g(6,2) in the sixth row is turned on. <1> and signal TX2 <1> becomes high level, and the transfer units 12a and connection units 14a are turned on in the pixels in the fifth and sixth rows.

[0062] Furthermore, at time t2, the signal FDSW <1> and signal TX3 <0> When the signal TX3 goes high, the transistor M7 of the connection unit 25B and the transistor M1b of the transfer unit 12b of the G pixel 10g(4,2) are turned on. <0> and signal FDSW <1> and signal TX1 <1> and signal TX2 <1> and the signal RST <1> and GND become high level. In this case, the photoelectric conversion unit 11b and storage unit 13b of the G pixel 10g(4,2) and the photoelectric conversion unit 11a, storage unit 13a, and FD 15 of the B pixel 10b(5,2) are electrically connected to the supply unit 65. As a result, the charges in the FD 15, storage unit 13a, and photoelectric conversion unit 11a of the B pixel 10b(5,2) are discharged, and the voltages of the FD 15, storage unit 13a, and photoelectric conversion unit 11a are reset. In addition, the charges in the photoelectric conversion unit 11b and storage unit 13b of the G pixel 10g(4,2) are discharged via the connection unit 25B, and the voltages of the photoelectric conversion unit 11b and storage unit 13b are reset.

[0063] At time t3, signal TX1 <0> and signal TX2 <0> becomes high level. Signal TX1 <0> and signal TX2 <0> When the signal SEL1 goes high, the transfer unit 12a and the connection unit 14a in the first AF pixel 20a(3,2) are turned on, and the photoelectric conversion unit 11a and the FD 15 are electrically connected. Therefore, the charge photoelectrically converted by the photoelectric conversion unit 11a is transferred to the FD 15. Also, at time t3, the signal SEL1 <0> is at a high level. Therefore, a signal (photoelectric conversion signal) based on the charge generated by the photoelectric conversion unit 11a of the first AF pixel 20a(3,2) is output to the first vertical signal line 55a by the amplifier 17 and the first selector 18. The photoelectric conversion signal is input to the first processing unit 80a via the first vertical signal line 55a and converted into a digital signal.

[0064] At time t4, the signal SEL1 <0> becomes low level, and the first selection unit 18 is turned off. <1> At time t5, the signal RST <0> and signal TX1 <0> and signal TX2 <0> becomes high level, the charges in the FD 15, the storage unit 13a, and the photoelectric conversion unit 11a are discharged in the pixels in the third and fourth rows, and the voltages of the FD 15, the storage unit 13a, and the photoelectric conversion unit 11a are reset.

[0065] At time t6, the signal RST <0> At time t6, the signal SEL1 goes high, the charge of the FD15 is reset in the pixels in the third and fourth rows, and the voltage of the FD15 goes to the reset voltage. <0> When the signal CS1 goes high, the first selection units 18 are turned on in the pixels in the third and fourth rows. A dark signal based on the reset voltage of the G pixel 10g(4,2) is output to the first vertical signal line 55a by the amplifier unit 17 and the first selection unit 18. The dark signal of each pixel in the third row is input to the first processing unit 80a via the first vertical signal line 55a and converted into a digital signal.

[0066] Also, at time t6, the signal RST <1> becomes high level, the charge of FD15 is reset in the pixels in the fifth and sixth rows, and the voltage of FD15 becomes the reset voltage. <1> When the signal CS1 goes high, the second selection units 19 are turned on in the pixels in the fifth and sixth rows. A dark signal based on the reset voltage of the B pixel 10b(5,2) is output to the second vertical signal line 55b by the amplifier unit 17 and the second selection unit 19. The dark signal of each pixel in the fifth row is input to the second processing unit 80b via the second vertical signal line 55b and converted into a digital signal.

[0067] At time t7, signal TX3 <0> and signal TX4 <0> When the signal SEL1 goes high, the photoelectric conversion units 11b and the FDs 15 are electrically connected in the pixels in the third and fourth rows, and the charges photoelectrically converted by the photoelectric conversion units 11b are transferred to the FDs 15. <0> is at a high level. Therefore, a photoelectric conversion signal based on the charge generated in the photoelectric conversion unit 11b of the G pixel 10g(4,2) is output to the first vertical signal line 55a by the amplifier 17 and the first selector 18. The photoelectric conversion signal of each pixel in the fourth row is input to the first processing unit 80a via the first vertical signal line 55a and converted into a digital signal.

[0068] Also, at time t7, the signal TX1 <1> and signal TX2 <1> When the signal SEL2 goes high, the photoelectric conversion units 11a and the FDs 15 are electrically connected in the pixels in the fifth and sixth rows, and the charges photoelectrically converted by the photoelectric conversion units 11a are transferred to the FDs 15. <1> is at a high level. Therefore, a photoelectric conversion signal based on the charge generated in the photoelectric conversion unit 11a of the B pixel 10b(5,2) is output to the second vertical signal line 55b by the amplifier unit 17 and the second selector unit 19. The photoelectric conversion signal of each pixel in the fifth row is input to the second processing unit 80b via the second vertical signal line 55b and converted into a digital signal.

[0069] The processing units 80 (first processing unit 80a, second processing unit 80b) perform signal processing such as correlated double sampling using the dark signal converted into a digital signal and the photoelectric conversion signal, and then output the processed signal to the control unit 4. As described above, in this embodiment, the image sensor 3 can perform a reset operation on the photoelectric conversion unit 11 and the storage unit 13 by controlling the connection unit 25. The image sensor 3 can perform a reset operation on the photoelectric conversion unit 11 and the storage unit 13 via a path separate from the path used to read out pixel signals, thereby preventing a decrease in the quality of pixel signals read out by the readout operation.

[0070] According to the above-described embodiment, the following advantageous effects can be obtained: (1) The imaging element 3 includes a first photoelectric conversion unit (photoelectric conversion unit 11) that photoelectrically converts light to generate electric charges, a second photoelectric conversion unit that photoelectrically converts light to generate electric charges, a first accumulation unit (FD15) that accumulates the electric charges, a first transfer unit (transfer unit 12) that is connected to the first photoelectric conversion unit and transfers the electric charges, a first connection unit (connection unit 14) that can electrically connect the first transfer unit and the first accumulation unit, a second transfer unit that is connected to the second photoelectric conversion unit and transfers the electric charges, and a second connection unit (connection unit 15) that can electrically connect the second transfer unit and the first accumulation unit. The image sensor 3 according to the present embodiment includes a second connection section electrically connecting the first transfer section to the second storage section, a third photoelectric conversion section that photoelectrically converts light to generate electric charges, a second storage section that stores the electric charges, a third transfer section connected to the third photoelectric conversion section and that transfers the electric charges, a third connection section electrically connecting the third transfer section to the second storage section, and a fourth connection section (connection section 25) electrically connecting between the first transfer section and the first connection section or between the second transfer section and the second connection section, and between the third transfer section and the third connection section. As a result, by controlling the connection section 25, the image sensor 3 according to the present embodiment can reset the electric charges of the photoelectric conversion section 11 via a path different from the path used to read out pixel signals.

[0071] (2) In this embodiment, when reading out a signal based on charges generated in one of the first and second photoelectric conversion units, the charges in the other photoelectric conversion unit can be reset. This makes it possible to avoid a collision between the readout operation and the reset operation, and to suppress a deterioration in the quality of the pixel signal.

[0072] The following modifications are also within the scope of the present invention, and one or more of the modifications may be combined with the above-described embodiment.

[0073] (Variation 1) The image sensor 3 may read pixel signals while electrically coupling (connecting) multiple FDs 15 by controlling the connection units 25 and 14. FIG. 6 is a diagram showing a partial configuration example of an image sensor according to Modification 1. The example shown in FIG. 6 shows a B pixel 10b(1,2), a G pixel 10g(2,2), a first AF pixel 20a(3,2), a G pixel 10g(4,2), a B pixel 10b(5,2), a G pixel 10g(6,2), a B pixel 10b(7,2), and a G pixel 10g(8,2). FIG. 7 is a timing chart showing an example of the operation of the image sensor according to Modification 1.

[0074] During the period from time t2 to time t4 shown in FIG. <0> , signal FDSW <0> , and signal TX2 <1> becomes high level. As a result, the FD15 (FD15A) shared by the B pixel 10b(1,2) and the G pixel 10g(2,2) and the FD15 (FD15B) shared by the first AF pixel 20a(3,2) and the G pixel 10g(4,2) are electrically connected. In this case, when charges are transferred from the photoelectric conversion units 11 of these pixels, they are distributed to the two FD15s. That is, the charges transferred from the photoelectric conversion units 11 are stored separately in FD15A and FD15B. The capacity of the area to which charges are transferred from the photoelectric conversion unit 11 increases, making it possible to reduce the conversion gain when converting charges into voltage.

[0075] At time t2, the signal RST <0> and signal RST <1> At time t2, the signal SEL1 <0> and signal SEL1 <1> As a result, a dark signal based on the reset voltages of FD15A and FD15B is output to the first vertical signal line 55a by the first selection unit 18 shared by the B pixel 10b(1,2) and the G pixel 10g(2,2) and the first selection unit 18 shared by the first AF pixel 20a(3,2) and the G pixel 10g(4,2).

[0076] At time t3, signal TX1 <1> When the signal SEL1 goes high, the charge photoelectrically converted by the photoelectric conversion unit 11a of the first AF pixel 20a(3,2) is transferred to and accumulated in the FD15A and FD15B. <0> and signal SEL1 <1> is at a high level. Therefore, a signal based on the charges accumulated in FD15A and FD15B, that is, a photoelectric conversion signal of the first AF pixel 20a(3,2), is output to the first vertical signal line 55a.

[0077] 7, FD15A and FD15B are electrically connected to each other, as in the period from time t2 to time t4. <2> , signal FDSW <2> , and signal TX2 <3> becomes high level. As a result, the FD15 (FD15C) shared by the B pixel 10b (5,2) and the G pixel 10g (6,2) and the FD15 (FD15D) shared by the B pixel 10b (7,2) and the G pixel 10g (8,2) are electrically connected to each other.

[0078] At time t6, the signal RST <0> and signal RST <1> becomes high level, and the signal SEL1 <0> and signal SEL1 <1> As a result, a dark signal based on the reset voltage of FD15A and FD15B is output to the first vertical signal line 55a. Also, at time t6, the signal RST <2> and signal RST <3> becomes high level, and the signal SEL2 <2> and signal SEL2 <3> As a result, a dark signal based on the reset voltage of FD15C and FD15D is output to the second vertical signal line 55b.

[0079] At time t7, signal TX3 <1> and signal TX4 <1> When the signal SEL1 goes high, the charge photoelectrically converted by the photoelectric conversion unit 11b of the G pixel 10g(4,2) is transferred to and accumulated in the FD15A and FD15B. <0> and signal SEL1 <1> is at a high level. Therefore, a signal based on the charge accumulated in FD15A and FD15B, i.e., a photoelectric conversion signal of the G pixel 10g(4,2), is output to the first vertical signal line 55a. Also, at time t7, the signal TX1 <2> and signal TX2 <2> When the signal SEL2 goes high, the charge photoelectrically converted by the photoelectric conversion unit 11a of the B pixel 10b(5,2) is transferred to and accumulated in FD15C and FD15D. <2> and signal SEL2 <3> is at a high level. Therefore, a signal based on the charges accumulated in FD15C and FD15D, that is, a photoelectric conversion signal of the B pixel 10b(5,2), is output to the second vertical signal line 55b.

[0080] In the above, an example has been described in which both of the two first selection units 18 (or the two second selection units 19) are turned on to output pixel signals to the first vertical signal line 55a (or the second vertical signal line 55b). However, it is also possible to turn on either one of the two first selection units 18 to output pixel signals to the first vertical signal line 55a. It is also possible to turn on either one of the two second selection units 19 to output pixel signals to the second vertical signal line 55b.

[0081] (Variation 2) In the above-described embodiment, an example has been described in which two adjacent pixels share the FD 15 and the amplifier 17, but the pixel configuration is not limited to this. Three or more pixels may share the FD 15, etc. For example, four pixels may share the FD 15, etc.

[0082] (Variation 3) In the above-described embodiment, an example has been described in which a photodiode is used as the photoelectric conversion unit, but a photoelectric conversion film (organic photoelectric film) may also be used as the photoelectric conversion unit.

[0083] (Variation 4) In the above embodiment, a case has been described in which primary color (RGB) color filters are used in the imaging element 3, but complementary color (CMY) color filters may also be used.

[0084] (Variation 5) The imaging elements and imaging devices described in the above-mentioned embodiments and variations may be applied to cameras, smartphones, tablets, cameras built into PCs, in-vehicle cameras, cameras mounted on unmanned aerial vehicles (drones, radio-controlled aircraft, etc.), etc.

[0085] Although various embodiments and modifications have been described above, the present invention is not limited to these. Other embodiments that are conceivable within the scope of the technical idea of ​​the present invention are also included within the scope of the present invention. [Explanation of symbols]

[0086] 1...imaging device, 3...imaging element, 4a...imaging control unit, 4b...image processing unit, 4c...focus detection unit, 10...imaging pixel, 11a, 11b...photoelectric conversion unit, 12a, 12b...transfer unit, 13a, 13b...storage unit, 14a, 14b, 25...connection unit, 15...FD, 16...reset unit, 17...amplification unit, 18...first selection unit, 19...second selection unit, 20a...first AF pixel, 20b...second AF pixel, 43...light shielding unit, 60, 65...supply unit, 70...readout control unit, 80a...first processing unit, 80b...second processing unit

Claims

[Claim 1] a first photoelectric conversion unit that converts light into electric charges; a second photoelectric conversion unit that converts light into electric charges; a third photoelectric conversion unit that converts light into electric charges; a fourth photoelectric conversion unit that converts light into electric charges; a first accumulation unit that accumulates the charges converted by the first photoelectric conversion unit; a second accumulation unit that accumulates the charges converted by the second photoelectric conversion unit; a third accumulation unit that accumulates the charges converted by the third photoelectric conversion unit; a fourth accumulation unit that accumulates the charges converted by the fourth photoelectric conversion unit; The charge stored in the first storage section is transferred to the first floating diffusion section. a first transfer unit; Transfer the charge stored in the second storage section to the first floating diffusion section a second transfer unit for transferring the The charge stored in the third storage section is transferred to the second floating diffusion section. a third transfer unit; The charge stored in the fourth storage section is transferred to the third floating diffusion section. a fourth transfer unit; a first connection portion that electrically connects the first storage portion and the third storage portion; a second connection portion that electrically connects the second storage portion and the fourth storage portion; The second transfer section transfers the charge from the second storage section to the first floating diffusion section. When the charge is being transferred to the third storage section, the charge is transferred from the first storage section to the third storage section via the first connection section. a first discharge section that discharges the charges transferred to the accumulation section to a first supply section that is supplied with a predetermined voltage; The first transfer section transfers the first storage section to the first floating diffusion section. When the charge is being transferred to the fourth storage section, the charge is transferred from the second storage section to the fourth storage section via the second connection section. a second discharge section that discharges the charges transferred to the accumulation section to a second supply section to which a predetermined voltage is supplied; An imaging element comprising:

Images