WO2023027017A1 - 撮像素子および撮像装置 - Google Patents
撮像素子および撮像装置 Download PDFInfo
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- H04N25/79—Arrangements of circuitry being divided between different or multiple substrates, chips or circuit boards, e.g. stacked image sensors
Definitions
- the present invention relates to an imaging device and an imaging device.
- Patent Document 1 An imaging device in which a plurality of pixels are two-dimensionally arranged in row and column directions is known (for example, Patent Document 1). An increase in power consumption of an image pickup device has been a problem from the past.
- An imaging device includes a first semiconductor substrate having a plurality of pixels arranged in a row direction, a first load current source supplying a current to a first pixel among the plurality of pixels, and the a second load current source that supplies a current to a second pixel among a plurality of pixels; a first pixel control section that controls current supply to the first pixel by the first load current source; and the second load current.
- a second semiconductor substrate having a second pixel control for controlling current supply to the second pixel by a source.
- An imaging device includes a first semiconductor substrate having a plurality of pixel blocks each including at least one pixel, and a second semiconductor substrate having a control block arranged for each of the pixel blocks, the control block has a pixel control section that controls a load current source that supplies a current to the pixels included in a corresponding pixel block among the plurality of pixel blocks.
- the imaging device of the third disclosed technology includes the imaging element of the first disclosed technology or the second disclosed technology.
- FIG. 1 is an exploded perspective view showing an example of an imaging device.
- FIG. 2 is an explanatory diagram showing an example of a specific configuration of a pixel portion.
- FIG. 3 is a circuit diagram showing an example of the circuit configuration of a pixel.
- FIG. 4 is an explanatory diagram showing an example of a specific configuration of the control circuit section.
- FIG. 5 is an explanatory diagram showing an example of the internal configuration of a control block.
- FIG. 6 is an explanatory diagram showing an example of signal transmission between the first semiconductor substrate and the second semiconductor substrate in the imaging device.
- FIG. 7 is an explanatory diagram showing an example of a cross section in the XZ direction of the imaging element according to this embodiment.
- FIG. 8 is a timing chart showing an imaging operation example 1 of the imaging device.
- FIG. 8 is a timing chart showing an imaging operation example 1 of the imaging device.
- FIG. 9 is a timing chart showing an imaging operation example 2 of the imaging device.
- FIG. 10 is a timing chart showing imaging operations of an imaging device according to a comparative example.
- FIG. 11 is an explanatory diagram showing an example of a subject imaged by an imaging device.
- FIG. 12 is a timing chart showing exposure time for each of regions 1 to 5 shown in FIG.
- FIG. 13 is a plan view showing a layout example of a plurality of control blocks.
- FIG. 14 is a circuit diagram showing another example of the circuit configuration of a pixel.
- FIG. 15 is a timing chart showing example 3 of imaging operation of the imaging device.
- FIG. 16 is an exploded perspective view showing another example of the imaging device.
- FIG. 17 is an explanatory diagram showing another example of the specific configuration of the control circuit section.
- FIG. 18 is an explanatory diagram showing the connection relationship between the first semiconductor substrate and the second semiconductor substrate in the imaging device.
- FIG. 19 is an explanatory diagram showing an example of signal transmission between the first semiconductor substrate and the second semiconductor substrate in the imaging device.
- FIG. 20 is an explanatory diagram showing the connection relationship between the ADC section and the pixel blocks.
- FIG. 21 is a timing chart showing imaging operations within a pixel block of the imaging device.
- FIG. 22 is an explanatory diagram showing an example of exposure timing for each pixel block.
- FIG. 23 is a block diagram showing a configuration example of the autonomous exposure control method 1.
- FIG. 24 is a block diagram showing a configuration example of the autonomous exposure control method 2.
- FIG. FIG. 24 is a block diagram showing a configuration example of the autonomous exposure control method 2.
- FIG. 25 is a block diagram showing a configuration example of the autonomous exposure control method 3.
- FIG. 26 is an explanatory diagram of a circuit configuration example inside a control block.
- FIG. 27 is an explanatory diagram of Example 1 of stopping circuit operation in units of control blocks.
- FIG. 28 is an explanatory diagram of Example 2 of stopping circuit operation in units of control blocks.
- FIG. 29 is an explanatory diagram of Example 3 of stopping circuit operation in units of control blocks.
- FIG. 30 is a truth table of the NAND circuit.
- FIG. 31 is a block diagram illustrating a configuration example of an imaging device according to an embodiment;
- the X-axis and the Y-axis are orthogonal to each other, and the Z-axis is orthogonal to the XY plane.
- the XYZ axes constitute a right-handed system.
- a direction parallel to the Z-axis may be referred to as a stacking direction of the imaging device 100 .
- the terms "upper” and “lower” are not limited to vertical directions in the direction of gravity. These terms refer only to relative directions in the Z-axis direction.
- the arrangement in the X-axis direction is described as a "row” and the arrangement in the Y-axis direction is described as a "column,” but the matrix direction is not limited to this.
- FIG. 1 The structure of the imaging device may be of a backside illumination type or a frontside illumination type.
- FIG. 1 is an exploded perspective view showing an example of the imaging device 100A.
- the imaging element 100A images a subject.
- the imaging device 100A generates image data of the captured subject.
- the imaging element 100A includes a first semiconductor substrate 110, a second semiconductor substrate 120 and a third semiconductor substrate . As shown in FIG. 1 , the first semiconductor substrate 110 is stacked on the second semiconductor substrate 120 , and the second semiconductor substrate 120 is stacked on the third semiconductor substrate 130 .
- the first semiconductor substrate 110 has a pixel section 101 .
- the pixel unit 101 outputs pixel signals based on incident light.
- the second semiconductor substrate 120 has a control circuit section 102 and a peripheral circuit section 121 .
- the control circuit unit 102 receives pixel signals output from the first semiconductor substrate 110 .
- the control circuit unit 102 processes input pixel signals.
- the control circuit section 102 is arranged at a position facing the pixel section 101 on the second semiconductor substrate 120 .
- the control circuit section 102 is arranged so as to overlap the pixel section 101 in the direction in which the first semiconductor substrate 110 and the second semiconductor substrate 120 are stacked.
- the control circuit unit 102 may output a control signal for controlling driving of the pixel unit 101 to the pixel unit 101 .
- the peripheral circuit section 121 controls driving of the control circuit section 102 .
- the peripheral circuit section 121 is arranged around the control circuit section 102 on the second semiconductor substrate 120 .
- the peripheral circuit section 121 is arranged in a region outside the region where the control circuit section 102 is arranged in the second semiconductor substrate 120 .
- the peripheral circuit section 121 may be electrically connected to the first semiconductor substrate 110 to control driving of the pixel section 101 .
- the peripheral circuit section 121 is arranged along two sides of the second semiconductor substrate 120, but the arrangement method of the peripheral circuit section 121 is not limited to this example.
- the third semiconductor substrate 130 has the data processing section 103 .
- the data processing unit 103 uses the digital data output from the second semiconductor substrate 120 to perform addition processing, thinning processing, and other image processing.
- FIG. 2 is an explanatory diagram showing an example of a specific configuration of the pixel unit 101.
- the pixel section 101 has a plurality of pixel blocks 200 .
- a plurality of pixel blocks 200 are arranged side by side in the row direction and the column direction in the pixel portion 101 .
- the plurality of pixel blocks 200 has M ⁇ N (M and N are natural numbers) pixel blocks 200 arranged in the row direction and the column direction in the pixel unit 101 .
- M is shown equal to N, M and N may be different.
- a pixel block 200 has a plurality of pixels 201 .
- a plurality of pixels 201 are arranged side by side in the row direction and the column direction in the pixel block 200 .
- the pixel block 200 has m ⁇ n (m and n are natural numbers) pixels 201 arranged in rows and columns.
- pixel block 200 has 16 ⁇ 16 pixels 201 arranged in rows and columns.
- the number of pixels 201 corresponding to the pixel block 200 is not limited to this. Although m is shown to be equal to n, m may be different from n.
- the pixel block 200 has a plurality of pixels 201 connected to common control lines (for example, transfer control lines 311 and discharge control lines 312, which will be described later) in the row direction.
- each pixel 201 of the pixel block 200 is connected to the common control line so as to be set to the same exposure time.
- every n pixels 201 arranged in the row direction are connected by the common control line.
- one pixel block 200 may be set to a different exposure time than the other pixel block 200.
- the plurality of pixels 201 of one pixel block 200 and the plurality of pixels 201 of the other pixel block 200 are different. Connected by a control line.
- a plurality of pixels 201 in the m-th row of one pixel block 200 are commonly connected by a control line different from the common control line to which the plurality of pixels 201 in the m-th row of the other pixel block 200 are connected. .
- the plurality of pixels 201 of one pixel block 200 and the plurality of pixels 201 of the other pixel block 200 are different. Connected by a control line. A plurality of pixels 201 in the m-th row of one pixel block 200 are commonly connected by a control line different from the common control line to which the plurality of pixels 201 in the m-th row of the other pixel block 200 are connected. .
- the plurality of pixels 201 of one pixel block 200 and the plurality of pixels 201 of the other pixel block 200 are connected by different signal lines 202 .
- a plurality of pixels 201 in the n-th column of one pixel block 200 are commonly connected by a signal line 202 different from the common signal line 202 to which the plurality of pixels 201 in the n-th column of the other pixel block 200 are connected.
- the plurality of pixels 201 of one pixel block 200 and the plurality of pixels 201 of the other pixel block 200 are different.
- a plurality of pixels 201 in the n-th column of one pixel block 200 are commonly connected by a signal line 202 different from the common signal line 202 to which the plurality of pixels 201 in the n-th column of the other pixel block 200 are connected. be done.
- the pixel block 200 is arranged corresponding to control blocks 400A and 400B (see FIGS. 4 and 17), which will be described later. That is, one pixel block 200 is arranged for one control block 400A, 400B.
- a plurality of pixel blocks 200 may be arranged for one control block 400A, 400B. Even when a plurality of pixel blocks 200 are arranged for one control block 400A, 400B, each pixel block 200 may be set to a different exposure time.
- the control blocks 400A and 400B control 2m ⁇ n pixels 201 .
- the control blocks 400A and 400B control 32 ⁇ 16 pixels 201, for example.
- the number of pixels 201 corresponding to control blocks 400A and 400B is not limited to this.
- FIG. 3 is a circuit diagram showing an example of the circuit configuration of the pixel 201.
- FIG. A pixel 201 includes a photoelectric conversion unit 300 and a readout unit 310 .
- the readout unit 310 includes a transfer unit 301, a discharge unit 302, an FD (floating diffusion) 303, a reset unit 304, and a pixel output unit 305.
- a pixel based on the charge converted by the photoelectric conversion unit 300 A signal is read out on the signal line 202 .
- the pixel output section 305 has an amplification section 351 and a selection section 352 .
- Reading section 310 Transfer section 301 , discharge section 302 , FD 303 , reset section 304 , amplification section 351 and selection section 352 are referred to as reading section 310 .
- the reading unit 310 is described as an N-channel FET, but the type of transistor is not limited to this.
- the photoelectric conversion unit 300 has a photoelectric conversion function of converting light into charge.
- the photoelectric conversion unit 300 accumulates photoelectrically converted charges.
- Photoelectric conversion unit 300 is configured by, for example, a photodiode.
- a transfer unit 301 transfers the charge of the photoelectric conversion unit 300 to the FD 303 .
- the transfer section 301 controls electrical connection between the photoelectric conversion section 300 and the FD 303 .
- the transfer unit 301 is composed of, for example, transistors. Further, the transfer unit 301 may be an element that constitutes a part of a transistor that has at least a gate terminal, a part of the photoelectric conversion part 300 as a source terminal, and a part of the FD 303 as a drain terminal.
- a gate terminal of the transfer unit 301 is connected to a transfer control line 311 for inputting a transfer control signal ⁇ TX.
- the transfer control line 311 will be described later.
- the discharge unit 302 discharges the charges accumulated in the photoelectric conversion unit 300 to the power supply wiring supplied with the power supply voltage VDD.
- the discharge unit 302 controls connection between the photoelectric conversion unit 300 and the power wiring.
- the discharge unit 302 is configured by, for example, a transistor.
- the discharge portion 302 is an element that constitutes part of a transistor that has at least a gate terminal, a portion of the photoelectric conversion portion 300 as a source terminal, and a portion of the diffusion region connected to the power supply wiring as a drain terminal. There may be.
- a gate terminal of discharge unit 302 is connected to discharge control line 312 for inputting discharge control signal ⁇ PDRST.
- the discharge unit 302 discharges the charge of the photoelectric conversion unit 300 to the power supply wiring to which the power supply voltage VDD is supplied, the electric charge may be discharged to the power supply wiring to which the power supply voltage different from the power supply voltage VDD is supplied. good.
- the FD 303 is transferred from the photoelectric conversion unit 300 by the transfer unit 301 .
- the FD 303 accumulates charges transferred from the photoelectric conversion unit 300 .
- the reset unit 304 discharges the charge accumulated in the FD 303 to the power supply wiring supplied with the power supply voltage VDD.
- the reset unit 304 resets the potential of the FD 303 to the power supply voltage VDD, which is the reference potential.
- the reset unit 304 controls electrical connection between the FD 303 and power wiring.
- Reset unit 304 is configured by, for example, a transistor. Further, the reset unit 304 may be an element that constitutes part of a transistor that has at least a gate terminal, a part of the FD 303 as a source terminal, and a part of the diffusion region connected to the power supply wiring as a drain terminal. good.
- a gate terminal of the reset unit 304 is connected to a reset control line 313 for inputting a reset control signal ⁇ RST. The reset control line 313 will be described later.
- a pixel output unit 305 outputs a pixel signal based on the potential of the FD 303 to the signal line 202 .
- the pixel output section 305 has an amplification section 351 and a selection section 352 .
- the amplifier section 351 is configured by a transistor.
- the amplification unit 351 has a gate terminal connected to the FD 303 , a drain terminal connected to a power supply line supplied with a power supply voltage VDD, and a source terminal connected to the drain terminal of the selection unit 352 .
- the selection unit 352 controls electrical connections between the pixels 201 and the signal lines 202 .
- a pixel signal is output from the pixel 201 to the signal line 202 .
- the selection unit 352 is configured by a transistor.
- the selection unit 352 is an element that constitutes part of a transistor that has at least a gate terminal, a part of the amplification part 351 as a source terminal, and a part of the diffusion region connected to the signal line 202 as a drain terminal. There may be.
- a gate terminal of the selection section 352 is connected to a selection control line 314 extending over a plurality of pixel blocks 200 for inputting a selection control signal ⁇ SEL.
- a source terminal of the selector 352 is connected to the load current source 306 .
- a load current source 306 is connected to the signal line 202 and supplies current for reading pixel signals from the pixels 201 . Thereby, the operation of the amplifier 351 can be stabilized.
- a load current source 306 is also connected to the signal line 202 .
- the load current source 306 may be provided on the first semiconductor substrate 110 or may be provided on the second semiconductor substrate 120 .
- the FD 303 and the pixel output unit 305 may be shared with other pixels 201 .
- the FD 303 and the pixel output unit 305 may be shared by a plurality of pixels 201 arranged in rows or columns.
- the pixel 201 may be composed of a plurality of photoelectric conversion units 300 and transfer units 301 .
- FIG. 4 is an explanatory diagram showing an example of a specific configuration of the control circuit section 102.
- the control circuit section 102 has a plurality of control blocks 400A.
- a plurality of control blocks 400A are arranged side by side in the row direction and the column direction in the control circuit portion 102 .
- the control circuit section 102 has M ⁇ N control blocks 400A.
- the control circuit section 102 has the control block 400A immediately below the pixel block 200.
- FIG. One pixel block 200 and one control block 400A have substantially the same shape and size.
- control circuit unit 102 arranges one control block 400A immediately below the plurality of pixel blocks 200 arranged in the column direction. It has a control block 400A.
- the control block 400A is provided corresponding to the pixel block 200.
- the control block 400A is positioned directly below the pixel block 200 in the direction in which the first semiconductor substrate 110 and the second semiconductor substrate 120 are stacked (stacking direction).
- the control block 400A is electrically connected to the pixel block 200 by the signal line 202, the transfer control line 311 and the discharge control line 312.
- FIG. Specifically, the control block 400A positioned immediately below the pixel block 200 in the stacking direction is controlled by local control lines such as the transfer control line 311 and the discharge control line 312 to control the pixel block 200 directly above in the stacking direction. It is electrically connected to the pixel block 200).
- the control block 400A inputs pixel signals output from the pixels 201 of the corresponding pixel block 200 via the signal line 202 .
- the control block 400A controls driving of the corresponding pixel block 200.
- control block 400A controls the exposure time of pixels 201 included in corresponding pixel block 200 .
- the control block 400A also has a signal processing unit 402 that processes the input signal, and processes the pixel signal output from the pixel 201 included in the corresponding pixel block 200.
- FIG. For example, the control block 400A converts analog pixel signals output from the pixels 201 included in the corresponding pixel block 200 into digital signals.
- the control block 400A has a pixel control section 401 and a signal processing section 402 .
- the pixel control unit 401 has an autonomous exposure processing unit 411 , an exposure control unit 412 and a pixel driving unit 413 and controls the pixels 201 of the pixel unit 101 .
- the signal processing unit 402 includes a signal input unit 421, a signal conversion unit 422, and a signal output unit 423, converts analog pixel signals from the pixel unit 101 into digital signals, and outputs them to the pixel control unit 401 and data processing. transfer to unit 103;
- the autonomous exposure processing unit 411 is a circuit that calculates the exposure time of the pixels 201 included in the corresponding pixel block 200 based on the pixel signals converted into digital signals by the signal processing unit 402 . Details of the autonomous exposure processing unit 411 will be described later.
- the exposure control unit 412 is a circuit that controls exposure of the pixels 201 included in the corresponding pixel block 200 based on the exposure time calculated by the autonomous exposure processing unit 411 . Specifically, the exposure control unit 412 generates a control signal for controlling the exposure time of the pixels 201 included in the corresponding pixel block 200 (the charge accumulation time of the photoelectric conversion unit 300). For example, the exposure control unit 412 controls the exposure time of each pixel block 200 by adjusting the exposure start timing or end timing of the pixels 201 included in the corresponding pixel block 200 .
- the exposure controller 412 is provided extending in the row direction in the control block 400A.
- the pixel drive section 413 outputs the control signal generated by the exposure control section 412 to the pixels 201 included in the corresponding pixel block 200 .
- the pixel drive section 413 is a drive circuit that drives the pixels 201 included in the corresponding pixel block 200 .
- the pixel driving section 413 drives the pixels 201 in the pixel row selected from the pixels 201 included in the corresponding pixel block 200 .
- the pixel driving unit 413 is provided extending in the column direction. Accordingly, the pixel drive unit 413 is arranged at a position corresponding to the m pixels 201 arranged in the column direction.
- the pixel driving section 413 extends in the column direction, and the autonomous exposure processing section 411 and the exposure control section 412 extend in the row direction. Therefore, they are arranged in an L shape.
- the signal input unit 421 inputs pixel signals output from the pixels 201 included in the corresponding pixel block 200 .
- the signal input section 421 outputs the input pixel signal to the signal conversion section 422 .
- the signal input section 421 may be provided for every n pixels 201 arranged in the row direction in the corresponding pixel block 200 .
- the signal input unit 421 may have a processing circuit that performs signal processing such as noise removal processing on pixel signals output from the first semiconductor substrate 110 .
- the signal input unit 421 may have a voltage adjustment circuit that adjusts the voltage of the signal line 202 connected to the pixel 201 included in the corresponding pixel block 200 so that the voltage does not fall below a predetermined value.
- the load current source 306 When the load current source 306 is arranged on the second semiconductor substrate, it may be arranged on the signal input section 421 included in the corresponding control block 400A.
- the signal conversion unit 422 converts the pixel signal output from the signal input unit 421 into a digital signal.
- the signal conversion unit 422 sequentially converts the pixel signals output from the m pixels 201 arranged in the column direction in the corresponding pixel block 200 into digital signals.
- the signal conversion unit 422 converts pixel signals output from the pixels 201 arranged in n columns in the row direction in the corresponding pixel block 200 into digital signals in parallel.
- the signal output unit 423 stores pixel signals converted into digital signals by the signal conversion unit 422 .
- the signal output section 423 may have a latch circuit for storing digital signals.
- the signal output section 423 is arranged between the signal conversion section 422 and the autonomous exposure processing section 411 in the column direction.
- the signal output unit 423 outputs the pixel signal converted into the digital signal to the outside of the control circuit unit 102 .
- the signal output unit 423 is provided extending in the row direction in the control block 400A.
- the signal output section 423 is arranged between the signal conversion section 422 and the autonomous exposure processing section 411 in the column direction.
- FIG. 5 is an explanatory diagram showing an example of the internal configuration of the control block 400A.
- the signal conversion unit 422 includes n comparators 501 and n storage units 502 .
- the exposure controller 412 includes a pixel block controller 503 and a level shifter 504 .
- a combination of one comparator 501 and a storage unit 502 connected to the comparator 501 constitutes one ADC (Analog-to-Digital Converter) 500 .
- ADC Analog-to-Digital Converter
- the comparator 501 is provided extending in the column direction in the control block 400A.
- the n comparators 501 are arranged side by side in the row direction.
- the comparator 501 is arranged for every m pixels 201 arranged in the column direction in the corresponding pixel block 200 .
- the comparator 501 sequentially reads pixel signals of m pixels 201 arranged in the column direction in the corresponding pixel block 200 and converts them into digital signals.
- a storage unit 502 stores pixel signals converted into digital signals using the comparator 501 .
- the storage unit 502 is provided on the negative side in the Y-axis direction of the comparator 501 in the signal conversion unit 422 .
- storage unit 502 has a latch circuit.
- the storage unit 502 may have a memory configured by an SRAM or the like.
- the pixel block control unit 503 controls the operations of the transfer unit 301 and the discharge unit 302 of the pixels 201 included in the corresponding pixel block 200 . Specifically, the pixel block control unit 503 controls the transfer control signal ⁇ TX for controlling the transfer unit 301 included in the pixel 201 included in the corresponding pixel block 200, and the discharge unit included in the pixel 201 included in the corresponding pixel block 200. A discharge control signal ⁇ PDRST for controlling 302 is output.
- the pixel block control section 503 is provided extending in the row direction in the control block 400A.
- the pixel block controller 503 is arranged between the level shifter 504 and the autonomous exposure processor 411 in the column direction.
- a level shifter 504 adjusts the voltage level of the control signal output from the pixel block controller 503 . Specifically, the level shifter 504 boosts the voltage level of the transfer control signal ⁇ TX output from the pixel block controller 503 . Also, the level shifter 504 boosts the voltage level of the discharge control signal ⁇ PDRST output from the pixel block controller 503 .
- the transfer unit 301 inputs the transfer control signal ⁇ TX boosted by the pixel block control unit 503 via the transfer control line 311 .
- the discharge unit 302 inputs the discharge control signal ⁇ PDRST boosted by the pixel block control unit 503 via the discharge control line 312 .
- the pixel block control section 503 boosts the transfer control signal ⁇ TX and the discharge control signal ⁇ PDRST to the voltage levels used in the transfer section 301 and discharge section 302 of the readout section 310 of the pixel 201 .
- the level shifter 504 is provided extending in the row direction in the control block 400A.
- the level shifter 504 is provided closer to the outer circumference of the control block 400A than the pixel block controller 503 is.
- the positive end in the X-axis direction and the negative end in the Y-axis direction of the level shifter 504 are located on the outermost side of the control block 400A.
- the negative end of the level shifter 504 in the X-axis direction is in contact with the pixel driver 413 .
- the level shifter 504 and the pixel driver 413 handle signals after level shifting.
- the autonomous exposure processing unit 411 , pixel block control unit 503 , level shift unit 504 and pixel driving unit 413 handle pixel signals output from the first semiconductor substrate 110 .
- each configuration of the control block 400A is formed in a well region provided in the second semiconductor substrate 120.
- FIG. The well regions are separated according to the voltage level of the signal to be handled.
- the well regions are separated depending on whether the power supply used is a digital power supply or an analog power supply. Further, even when the same analog power supply is used, the signal conversion section 422 may be separated from areas using other analog power supplies from the viewpoint of noise. Separation of well regions requires well isolation regions spaced according to manufacturing process rules.
- the control block 400A separates well regions for forming the level shifter 504 and the pixel driver 413 from other well regions.
- the level shifter 504 and the pixel driver 413 can share the well region of the level shifter 504 and the pixel driver 413 by being provided in an L shape. By sharing the well region, the well isolation region can be omitted, thereby improving layout efficiency.
- the L-shaped pixel control unit 401 constitutes part of the outer circumference of the control block 400A. This allows the well region to be shared with other control blocks 400A adjacent in the row and column directions.
- FIG. 6 is an explanatory diagram showing an example of signal transmission between the first semiconductor substrate 110 and the second semiconductor substrate 120 in the imaging element 100A.
- the global driving section 600 is provided in the peripheral circuit section 121 arranged on both sides of the control circuit section 102 .
- the transfer control line 311a and the discharge control line 312a are each connected to the pixels 201 included in the pixel block 200a.
- the transfer control line 311a is connected to the gate terminal of the transfer section 301 of the pixel 201 included in the pixel block 200a
- the discharge control line 312a is connected to the gate terminal of the discharge section 302 of the pixel 201 included in the pixel block 200a. be done.
- the transfer control line 311a supplies the transfer control signal ⁇ TX output from the control block 400Aa to the transfer units 301 of the pixels 201 included in the pixel block 200a.
- the discharge control line 312a supplies the discharge control signal ⁇ PDRST output from the control block 400Aa to the discharge section 302 of the pixel 201 included in the pixel block 200a.
- the transfer control line 311b and the discharge control line 312b are each connected to the pixels 201 included in the pixel block 200b.
- the transfer control line 311b is connected to the gate terminal of the transfer section 301 of the pixel 201 included in the pixel block 200b
- the discharge control line 312b is connected to the gate terminal of the discharge section 302 of the pixel 201 included in the pixel block 200b. be done.
- the transfer control line 311b supplies the transfer control signal ⁇ TX output from the control block 400Ab to the transfer units 301 of the pixels 201 included in the pixel block 200b.
- the discharge control line 312b supplies the discharge control signal ⁇ PDRST output from the control block 400Ab to the discharge units 302 of the pixels 201 included in the pixel block 200b.
- the transfer control lines 311a and 311b are referred to as a transfer control line 311 when not distinguished from each other.
- the emission control line 312a and the emission control line 312b are referred to as the emission control line 312 when they are not distinguished from each other.
- the transfer control line 311 and the discharge control line 312 are examples of local control lines connected to the first pixel of the pixel block 200 .
- the transfer control line 311 and the discharge control line 312 are commonly connected to the n pixels 201 arranged in the row direction in the pixel block 200 .
- the global driving section 600 outputs a reset control signal ⁇ RST, a selection control signal ⁇ SEL and a transfer selection control signal ⁇ TXSEL.
- the global driver 600 is connected to reset control lines 313 , select control lines 314 , and transfer select control lines 603 that output control signals to respective pixel blocks 200 .
- the global driving section 600 supplies the reset control signal ⁇ RST and the selection control signal ⁇ SEL to the plurality of pixel blocks 200 via the reset control line 313 and the selection control line 314 .
- the global driver 600 supplies a transfer selection control signal ⁇ TXSEL to the plurality of control blocks 400A through the transfer selection control line 603.
- a transfer selection control signal ⁇ TXSEL is supplied from the global driving section 600 to the control block 400A in order to control the exposure time of each pixel block 200.
- the control block 400 A supplied with the transfer selection control signal ⁇ TXSEL outputs the transfer selection control signal ⁇ TXSEL to the corresponding pixel block 200 .
- the control block 400A determines whether to input the transfer selection control signal ⁇ TXSEL to the pixel 201 as the transfer control signal ⁇ TX or the discharge control signal ⁇ PDRST. As a result, the input of the transfer control signal ⁇ TX or the discharge control signal ⁇ PDRST to the pixel 201 is skipped.
- the control block 400A extends the exposure time by skipping the transfer control signal ⁇ TX. Further, when the transfer control signal ⁇ TX determines the exposure start time, the control block 400A can shorten the exposure time by skipping the transfer control signal ⁇ TX. Thus, the exposure time of the pixel block 200 can be adjusted by the transfer selection control signal ⁇ TXSEL. The same is true when the discharge control signal ⁇ PDRST determines the start time or end time of exposure.
- a reset control line 313 , a selection control line 314 , and a transfer selection control line 603 are commonly provided for a plurality of pixel blocks 200 .
- the reset control lines 313, the selection control lines 314, and the transfer selection control lines 603 are wired across the first semiconductor substrate 110 in the row direction.
- the reset control lines 313, the selection control lines 314, and the transfer selection control lines 603 may be wired across the first semiconductor substrate 110 in the column direction.
- the reset control line 313 is connected to the gate terminal of the reset section 304 of the pixel 201 in the pixel block 200 and supplies the reset control signal ⁇ RST.
- the selection control line 314 is connected to the gate terminal of the selection section 352 of the pixel 201 in the pixel block 200 and supplies the selection control signal ⁇ SEL.
- a transfer selection control line 603 is connected to each of the plurality of control blocks 400A and supplies a transfer selection control signal ⁇ TXSEL to the pixel control section 401 .
- the global drive unit 600 outputs the transfer selection control signal ⁇ TXSEL from the second semiconductor substrate 120 via the first semiconductor substrate 110 to the control block 400A.
- a transfer selection control signal ⁇ TXSEL may be output to the block 400A.
- the transfer selection control line 603 is provided on the second semiconductor substrate 120 .
- the bonding portion 610 is provided on the bonding surface where the first semiconductor substrate 110 and the second semiconductor substrate 120 are bonded to each other.
- the junction 610 aligns the transfer control line 311 , the discharge control line 312 , and the transfer selection control line 603 between the first semiconductor substrate 110 and the second semiconductor substrate 120 .
- Each of the joints 610 is composed of a pair of conductive joint pads, which are joined by pressure treatment or the like on the first semiconductor substrate 110 and the second semiconductor substrate 120 to be electrically connected.
- the imaging element 100A controls the exposure time for each pixel block 200 by changing the timing of at least one of the transfer section 301 and the discharge section 302 by local control lines such as the transfer control line 311 and the discharge control line 312. .
- local control lines such as transfer control line 311 and discharge control line 312
- global control lines such as reset control line 313, select control line 314, and transfer select control line 603, imager 100A can achieve more Control of the exposure time can be realized with a small number of control lines.
- FIG. 7 is an explanatory diagram showing an example of an XZ direction cross section of the imaging element 100A according to this embodiment.
- the imaging device 100A includes a microlens layer 700, a color filter layer 702, a first semiconductor substrate 110, a second semiconductor substrate 120, and a third semiconductor substrate .
- the light from the object is incident in the direction indicated by the white arrow (negative Z-axis direction in the figure).
- the surface of the first semiconductor substrate 110 on which light is incident (the Z-axis positive side in the drawing) may be referred to as the front surface, and the opposite surface (the Z-axis negative side in the drawing) may be referred to as the back surface. .
- the microlens layer 700 has a plurality of microlenses 701 .
- a plurality of microlenses 701 are stacked on the Z-axis positive side of the color filter layer 702 .
- Light is incident on the microlens 701 .
- the microlens 701 converges incident light onto the photoelectric conversion unit 300 .
- a microlens 701 may be provided for each photoelectric conversion unit 300 .
- the optical axis L of the microlens 701 is the stacking direction (direction parallel to the Z-axis) of the first semiconductor substrate 110, the second semiconductor substrate 120, and the third semiconductor substrate .
- the color filter layer 702 has a plurality of color filters 703 and a passivation film 704.
- the color filter layer 702 is stacked on the Z-axis positive side of the first semiconductor layer 711 .
- a color filter 703 is an optical filter that transmits light in a specific wavelength range.
- a color filter 703 is an optical filter having specific spectral characteristics.
- the plurality of color filters 703 have a plurality of optical filters with different spectral characteristics and transmit light in different wavelength regions.
- a plurality of color filters 703 are provided in a specific arrangement (eg, Bayer arrangement).
- the first semiconductor substrate 110 is a back-illuminated CMOS image sensor.
- the first semiconductor substrate 110 has a first semiconductor layer 711 and a first wiring layer 712 .
- the first semiconductor layer 711 is provided on the Z-axis positive side of the first wiring layer 712 .
- the first semiconductor layer 711 has a plurality of pixel blocks 200 two-dimensionally arranged in the row direction and the column direction.
- the first semiconductor layer 711 has a plurality of pixels 201 two-dimensionally arranged in the row direction and the column direction.
- the pixels 201 each have a plurality of photoelectric conversion units 300 that accumulate charges based on incident light, and a plurality of readout units 310 .
- the first wiring layer 712 is provided closer to the second semiconductor substrate 120 than the first semiconductor layer 711 (the Z-axis negative side in the drawing).
- the first wiring layer 712 has a plurality of wirings 713 made of a conductor film (metal film), a plurality of bonding pads 714, and an insulating film (insulating layer).
- the first wiring layer 712 has a plurality of wirings 713 electrically connected to a power source, a circuit, or the like.
- the wiring 713 is specifically, for example, a power supply wiring to which a predetermined power supply voltage is supplied, and transmits pixel signals from the first semiconductor substrate 110 (pixels) to the second semiconductor substrate 120 .
- the first wiring layer 712 may be multi-layered and may be provided with passive elements and active elements.
- the bonding pad 714 is provided on the surface (surface on the Z-axis negative side) of the first wiring layer 712 and connected to the wiring 713 .
- Bond pads 714 are also used to assist in connecting layers, as described below.
- Bond pads 714 are formed of a conductive material such as, for example, copper. Note that the bond pads 714 may be made of gold, silver, or aluminum.
- An insulating layer (insulating film) is formed between the plurality of wirings 713 and between the plurality of bonding pads 714 .
- the second semiconductor substrate 120 has a second semiconductor layer 721 , a second wiring layer 722 and a wiring layer 723 .
- the second wiring layer 722 is provided closer to the first semiconductor substrate 110 than the second semiconductor layer 721 (on the Z-axis positive side in the drawing).
- the wiring layer 723 is provided closer to the third semiconductor substrate 130 than the second semiconductor layer 721 (the Z-axis negative side in the drawing), and is provided between the second semiconductor layer 721 and the third semiconductor substrate 130 .
- the second semiconductor layer 721 has the control circuit section 102 and the peripheral circuit section 121 .
- the control circuit section 102 has a plurality of control blocks 400A arranged two-dimensionally in the row direction and the column direction.
- the second semiconductor substrate 120 includes a plurality of wirings 713 provided on the second wiring layer 722 and a plurality of bonding pads 714 provided on the second wiring layer 722 and the wiring layer 723 . , and insulating films (insulating layers) provided in the second wiring layer 722 and the wiring layer 723 .
- the second wiring layer 722 is used to electrically connect to a power source, a circuit, or the like, to transmit signals from the pixel portion 101 to the control circuit portion 102, and to transmit signals from the control circuit portion 102 to the pixel portion 101. , a plurality of traces 713 and bonding pads 714 .
- the wiring 713 is specifically, for example, a power supply wiring to which a predetermined power supply voltage is supplied, and transmits pixel signals from the first semiconductor substrate 110 (pixels) to the second semiconductor substrate 120 .
- the second wiring layer 722 may be multi-layered and may be provided with passive elements and active elements. Wiring 713 and bond pads 714 may be further provided on wiring layer 723 .
- the second semiconductor substrate 120 further has TSVs (through silicon vias) 724 that connect the circuits respectively provided on the front and back surfaces.
- TSVs 724 are preferably provided in the peripheral region.
- the TSV 724 transmits image data and the like generated by the data processing unit 103 to the first semiconductor substrate 110 .
- the TSV 724 may also be provided on the first semiconductor substrate 110 and the third semiconductor substrate 130 .
- the third semiconductor substrate 130 has a third semiconductor layer 731 provided with the data processing section 103 and a third wiring layer 732 .
- the third wiring layer 732 is provided between the third semiconductor layer 731 and the second semiconductor substrate 120 .
- the third semiconductor substrate 130 has wiring 713 and a plurality of bonding pads 714 provided in a third wiring layer 732, like the first semiconductor substrate 110.
- the third wiring layer 732 is for electrically connecting to a power supply or a circuit, etc., for transmitting signals from the control circuit section 102 to the data processing section 103, and for transmitting signals from the data processing section 103 to the second semiconductor substrate. It has a plurality of wires 713 and bonding pads 714 for transmission to the control circuitry 102 of 120 .
- the first semiconductor substrate 110, the second semiconductor substrate 120, and the third semiconductor substrate 130 are laminated by electrical connection between the bonding pads 714 provided on each layer and bonding between wiring layers (insulating layers) on each layer. be done.
- the surface of the first wiring layer 712 on the Z-axis negative side and the surface of the second wiring layer 722 on the Z-axis positive side form a boundary surface 720.
- a boundary surface 730 is formed between the surface of the wiring layer 723 on the Z-axis negative side and the surface of the third wiring layer 732 on the Z-axis positive side.
- a plurality of bond pads 714 are disposed on interface 720 and interface 730 . Specifically, corresponding bond pads 714 are aligned and the two layers are laminated to electrically connect the aligned bonds.
- the first semiconductor substrate 110, the second semiconductor substrate 120, and the third semiconductor substrate 130 may be stacked in the state of wafers before chipping, and formed (individualized) by dicing the stacked wafers.
- the first semiconductor substrate 110, the second semiconductor substrate 120, and the third semiconductor substrate 130 may be formed by laminating after dicing each wafer.
- FIG. 8 is a timing chart showing imaging operation example 1 of the imaging device 100A.
- FIG. 8 shows an example of an imaging operation in which driving of the imaging element 100A is controlled by the transfer control signal ⁇ TX, discharge control signal ⁇ PDRST, reset control signal ⁇ RST, and selection control signal ⁇ SEL.
- discharge control signal ⁇ PDRST is locally controlled
- transfer control signal ⁇ TX, reset control signal ⁇ RST and select control signal ⁇ SEL are globally controlled. ⁇ 1>, ⁇ 2>, .
- the discharge control signal ⁇ PDRST controls the timing of starting exposure.
- the exposure start timing corresponds to the fall timing of the discharge control signal ⁇ PDRST (for example, time T1). That is, before the exposure start time T1, the discharge control signal ⁇ PDRST turns on the discharge unit 302 to discharge the charges accumulated in the photoelectric conversion unit 300, and the exposure starts at the fall of the discharge control signal ⁇ PDRST. do. Since the discharge control signal ⁇ PDRST is locally controlled, the exposure time can be adjusted for each pixel block 200 .
- the transfer control signal ⁇ TX controls the timing of ending exposure.
- the transfer control signal ⁇ TX turns on the transfer unit 301 to transfer the charge accumulated in the photoelectric conversion unit 300 to the FD 303 .
- the end timing of exposure corresponds to the falling timing of the transfer control signal ⁇ TX (for example, time T4). Since the transfer control signal ⁇ TX is a globally controlled signal, the timing of ending exposure in each pixel block 200 is the same.
- the reset control signal ⁇ RST controls the timing of discharge of charges accumulated in the FD 303 .
- the reset control signal ⁇ RST turns on the reset section 304 to discharge the charge of the FD 303 .
- a selection control signal ⁇ SEL is a signal for selecting an arbitrary pixel 201 .
- the selection control signal ⁇ SEL controls on/off of the selection section 352 .
- the selection control signal ⁇ SEL is set high.
- the imaging element 100A can change the exposure start timing for each pixel block 200 and control the exposure time for each pixel block 200 by locally controlling the discharge control signal ⁇ PDRST. Further, the imaging device 100A may control the end timing of exposure for each pixel block 200 by locally controlling the transfer control signal ⁇ TX. The imaging element 100A may control both the start timing and the end timing of exposure for each pixel block 200 by locally controlling both the transfer control signal ⁇ TX and the discharge control signal ⁇ PDRST.
- FIG. 9 is a timing chart showing an imaging operation example 2 of the imaging element 100A.
- FIG. 9 shows an example of an imaging operation in which driving of the imaging element 100A is controlled by the transfer control signal ⁇ TX, reset control signal ⁇ RST, and selection control signal ⁇ SEL.
- the imaging element 100A differs from the case of FIG. 8 in that the timing of starting exposure is controlled by the transfer control signal ⁇ TX. Points different from FIG. 8 will be particularly described.
- the transfer control signal ⁇ TX controls the timing of starting and ending exposure. In frame (n), exposure starts at time T5 and ends at time T7.
- exposure starts when the transfer control signal ⁇ TX falls. That is, before the exposure start time T5, the transfer control signal ⁇ TX turns on the transfer unit 301 while the reset control signal ⁇ RST is turned on, thereby discharging the charge accumulated in the photoelectric conversion unit 300. Exposure starts at the fall of the transfer control signal ⁇ TX. Since the transfer control signal ⁇ TX is a locally controlled signal, it is possible to change the timing of starting exposure in each pixel block 200 . However, the timing of starting exposure in each pixel block 200 may be matched.
- the transfer control signal ⁇ TX falls, thereby ending the exposure. That is, before the exposure end time T7, the transfer control signal ⁇ TX turns on the transfer unit 301 while the reset control signal ⁇ RST is turned off, thereby transferring the charge accumulated in the photoelectric conversion unit 300 to the FD 303. Then, the exposure ends when the transfer control signal ⁇ TX falls. Since the transfer control signal ⁇ TX is a locally controlled signal, it is possible to change the timing of ending exposure in each pixel block 200 . However, the timing of ending exposure in each pixel block 200 may be matched.
- a selection control signal ⁇ SEL is a signal for selecting an arbitrary pixel 201 .
- the reset control signal ⁇ RST controls the timing of discharge of charges accumulated in the FD 303 .
- Reset control signal ⁇ RST may be a globally controlled signal. Since the reset control signal ⁇ RST is always on except at the read timing, the FD 303 is not charged. On the other hand, by turning off the reset control signal ⁇ RST and turning on the transfer control signal ⁇ TX at the read timing, charges are transferred from the photoelectric conversion unit 300 to the FD 303 . Since the reset control signal ⁇ RST has the same switching timing during reading, it can be shared with the pulse of the selection control signal ⁇ SEL.
- the imaging device 100A can change the timing of starting or ending exposure for each pixel block 200 and control the exposure time for each pixel block 200 .
- the control circuit can be further simplified.
- FIG. 10 is a timing chart showing the imaging operation of the imaging device according to the comparative example.
- FIG. 10 shows an imaging operation example in which driving of the imaging device is controlled by the transfer control signal ⁇ TX, reset control signal ⁇ RST, and selection control signal ⁇ SEL, and the exposure time is not controlled for each pixel block 200 .
- the start of exposure is controlled by the transfer control signal ⁇ TX and the reset control signal ⁇ RST.
- the exposure start timing is the fall timing (time t1) of the transfer control signal ⁇ TX and the reset control signal ⁇ RST.
- the end timing of exposure is the fall timing (time t2) of the transfer control signal ⁇ TX.
- the exposure start timing and end timing are globally controlled, and the exposure time is not controlled for each pixel block 200 .
- FIG. 11 is an explanatory diagram showing an example of a subject imaged by the imaging device 100A.
- the imaging device 100A controls the exposure time for each pixel block 200 in a situation where the afternoon sun is shining outside the tunnel.
- Areas 1 to 5 are five areas divided according to brightness. Regions 1 to 5 are numbered in ascending order of brightness. Area 1 is the brightest area where the afternoon sun is directly visible. Region 2 is the region corresponding to the tunnel exit and is darker than region 1 . Area 3 is an area where the afternoon sun is reflected inside the tunnel and is darker than area 2 . Area 4 is an area in which the afternoon sun from the exit of the tunnel is inserted, and is darker than area 3 . Region 5 is the darkest region in the tunnel that is not exposed to the western sun from the exit.
- the imaging element 100A controls the exposure time for each pixel block 200 according to the brightness of each area.
- the image pickup device 100A performs control so that the exposure time of the pixel block 200 in a brighter area becomes shorter.
- the exposure time for area 1 is set to be the shortest, and the exposure time for area 5 is set to be the longest.
- the exposure times for regions 1 to 5 are 1/19200 s, 1/1920 s, 1/960 s, 1/240 s and 1/120 s.
- FIG. 12 is a timing chart showing the exposure time for each of regions 1-5 shown in FIG.
- the imaging device 100A controls the exposure time for each pixel block 200 of regions 1 to 5 shown in FIG.
- a section from time T11 to time T19 corresponds to the video frame rate.
- control block 400A controls driving so that the exposure time in the pixel block 200 is the predetermined exposure time ET1.
- the control block 400A controls the start of exposure with a discharge control signal ⁇ PDRST and the end of exposure with a transfer control signal ⁇ TX. In region 1, exposure is completed at each of time T12 to time T19.
- the control block 400A controls driving so that the exposure time in the pixel block 200 is an exposure time ET2 longer than ET1.
- the control block 400A makes the exposure start time of the area 2 earlier than that of the area 1, and makes the exposure end time of the area 1 match. Therefore, in region 2, exposure is completed at each of time T12 to time T19.
- the exposure time ET2 of region 2 is shorter than the period of the sensor rate.
- the control block 400A controls driving so that the exposure time in the pixel block 200 is an exposure time ET3 longer than ET2.
- the control block 400A makes the exposure start time of the area 3 earlier than that of the area 2, and matches the exposure end time of the area 2.
- FIG. Therefore, in region 3, exposure is completed at each of time T12 to time T19.
- the exposure time ET3 of region 3 is set to be the same as the period of the sensor rate.
- the control block 400A controls driving so that the exposure time in the pixel block 200 is an exposure time ET4 longer than ET3.
- the control block 400A sets the exposure start time for the area 4 to be the same as that for the area 3, but skips the exposure end time by the transfer selection control signal ⁇ TXSEL.
- the control block 400A realizes an exposure time four times that of the area 3 by skipping three times with the transfer selection control signal ⁇ TXSEL.
- the transfer selection control signal ⁇ TXSEL is supplied at each time from time T12 to time T14.
- the control block 400A controls driving so that the exposure time in the pixel block 200 is an exposure time ET5 longer than ET4.
- the control block 400A sets the exposure start time for region 5 to be the same as that for region 4, while increasing the number of times the exposure end time is skipped by the transfer selection control signal ⁇ TXSEL.
- the control block 400A realizes twice the exposure time of the area 4 by skipping seven times with the transfer selection control signal ⁇ TXSEL.
- the exposure time ET5 of the area 5 is set to be the same as the cycle of the moving picture frame rate.
- the transfer selection control signal ⁇ TXSEL is supplied at each time from time T12 to time T18.
- the imaging device 100A realizes short-second exposure by shortening the interval between the transfer control signal ⁇ TX and the ejection control signal ⁇ PDRST. Further, the imaging device 100 realizes long exposure by skipping the control of the transfer control signal ⁇ TX by the transfer selection control signal ⁇ TXSEL. Thereby, the dynamic range can be expanded.
- FIG. 13 is a plan view showing a layout example of a plurality of control blocks 400A.
- the plurality of control blocks 400A are reversely arranged with respect to adjacent control blocks 400A.
- FIG. 13 illustrates 12 control blocks 400A out of the plurality of control blocks 400A provided in the control circuit section 102. As shown in FIG.
- the reverse arrangement means that the regions in which each component of the control block 400A (for example, the exposure control unit 412, the pixel driving unit 413, the signal input unit 421, the signal conversion unit 422, and the signal output unit 423) are formed are arranged in the control blocks 400A. mirror-inverted arrangement (arranged symmetrically) around the boundary line. Even the circuits of each component of the control block 400A do not have to be reversed. Also, the readout order of each pixel in the control block 400A is not limited to being read out in reverse order.
- each configuration of the control block 400A is reversed in the row direction.
- the drive units 413 are arranged adjacent to each other.
- a plurality of pixel driving units 413 arranged side by side in the row direction can be laid out as one pixel driving unit 413, and the layout efficiency of the control block 400A can be improved.
- each configuration of the control blocks 400A is reversed in the column direction, so that the boundary between both control blocks 400A is the same.
- the configurations will be placed side by side.
- a plurality of signal input sections 421 arranged side by side in the column direction can be laid out as one signal input section 421, and the layout efficiency of the control block 400A can be improved.
- the control block 400A is reversely arranged with the adjacent control block 400A. All the control blocks 400A are reversed in the row direction and the column direction, but may be reversed in either the row direction or the column direction.
- the signal conversion section 422 of the control block 400A is reversely arranged with respect to the signal conversion section 422 of the adjacent control block 400A in the row direction.
- the signal conversion section 422 of the control block 400A is also reversely arranged with the signal conversion section 422 of the control block 400A adjacent in the column direction.
- the control block 400Aa and the control block 400Ab are arranged side by side in the row direction.
- the control block 400Aa is reversed from the control block 400Ab.
- the level shifter 504 of the control block 400Aa is provided in the same well region as the level shifter 504 of the control block 400Ab.
- the pixel block control section 503, the storage section 502 and the signal output section 423 are provided in the same well region in the control block 400Aa and the control block 400Ab.
- the control block 400Ab and the control block 400Ac are arranged side by side in the row direction.
- the control block 400Ab is reversed from the control block 400Ac.
- the pixel driving section 413 of the control block 400Ab is provided in the same well region as the pixel driving section 413 of the control block 400Ac.
- the well region of the pixel driver 413 may also be shared with the well region of the level shifter 504 .
- the control block 400Aa and the control block 400Ad are arranged side by side in the column direction.
- the control block 400Aa is reversed from the control block 400Ad.
- the pixel driving section 413 of the control block 400Aa is provided in the same well region as the pixel driving section 413 of the control block 400Ad.
- the signal conversion section 422 of the control block 400Aa is provided in the same well region as the signal conversion section 422 of the control block 400Ad.
- the control block 400Ad and the control block 400Ae are provided adjacent to each other in the column direction.
- the control block 400Ad is reversely arranged with respect to the control block 400Ae.
- the pixel drive section 413 and the level shift section 504 of the control block 400Ad are provided in the same well region as the pixel drive section 413 and the level shift section 504 of the control block 400Ae.
- the imaging device 100 can make the layout more efficient even when signal processing is performed in parallel for each control block 400A.
- adjacent control blocks 400A can share a well region by reversely arranging a plurality of control blocks 400A on the XY plane. This reduces the number of times the well regions are switched and improves area efficiency.
- FIG. 14 is a circuit diagram showing another example of the circuit configuration of the pixel 201.
- FIG. In the pixel 201 the same reference numerals are assigned to the same configurations as in FIG. 3, and the description thereof is omitted.
- the pixel 201 is not provided with the discharge section 302 provided in the pixel 201 .
- the transfer control signal ⁇ TX is input to the gate terminal of the transfer unit 301 and the reset control signal is applied to the gate terminal of the reset unit 304 .
- a signal ⁇ RST is input.
- FIG. 15 is a timing chart showing example 3 of the imaging operation of the imaging element 100A.
- FIG. 15 shows an image pickup operation example in which the pixel 201 shown in FIG. 14 uses the transfer control signal ⁇ TX, the reset control signal ⁇ RST, and the selection control signal ⁇ SEL to control driving of the image sensor 100A.
- the imaging element 100A differs from the case of FIG. 12 in that the timing of starting exposure is controlled by the transfer control signal ⁇ TX. Differences from FIG. 12 will be particularly described.
- the transfer control signal ⁇ TX controls the timing of starting and ending exposure. In frame (n), exposure starts at time T5 and ends at time T7.
- exposure starts when the transfer control signal ⁇ TX falls. That is, before the exposure start time T5, the transfer control signal ⁇ TX turns on the transfer unit 301 while the reset control signal ⁇ RST is turned on, thereby discharging the charge accumulated in the photoelectric conversion unit 300. Exposure starts at the fall of the transfer control signal ⁇ TX. Since the transfer control signal ⁇ TX is a locally controlled signal, it is possible to change the timing of starting exposure in each pixel block 200 .
- the transfer control signal ⁇ TX falls, thereby ending the exposure. That is, before the exposure end time T7, the transfer control signal ⁇ TX turns on the transfer unit 301 while the reset control signal ⁇ RST is turned off, thereby transferring the charge accumulated in the photoelectric conversion unit 300 to the FD 303. Then, the exposure ends when the transfer control signal ⁇ TX falls. Since the transfer control signal ⁇ TX is a locally controlled signal, it is possible to change the timing of ending exposure in each pixel block 200 .
- a selection control signal ⁇ SEL is a signal for selecting an arbitrary pixel 201 .
- the reset control signal ⁇ RST controls the timing of discharge of charges accumulated in the FD 303 .
- Reset control signal ⁇ RST may be a globally controlled signal. Since the reset control signal ⁇ RST is always on except at the read timing, the FD 303 is not charged. On the other hand, by turning off the reset control signal ⁇ RST and turning on the transfer control signal ⁇ TX at the read timing, charges are transferred from the photoelectric conversion unit 300 to the FD 303 . Since the reset control signal ⁇ RST has the same switching timing during reading, it can be shared with the pulse of the selection control signal ⁇ SEL.
- the pixel block 200 composed of a plurality of pixels 201 is exposed, and the control block 400A corresponding to the pixel block 200 is exposed.
- Pixel signals from 200 can be read out and converted from analog signals to digital signals.
- the image sensor 100A reads pixel signals in parallel for each pixel block 200 by means of a control block 400A provided for each pixel block 200.
- FIG. Therefore, the imaging element 100A can set the exposure time for each pixel block 200 according to the intensity of the incident light, so that the dynamic range can be expanded.
- the configuration of the imaging element 100B that performs exposure in units of pixel blocks 200, sequentially reads out pixel signals for each pixel row, and performs AD conversion for each pixel column will be described.
- FIG. 16 is an exploded perspective view showing another example of the imaging element.
- the imaging device 100B includes a first semiconductor substrate 110, a second semiconductor substrate 120 and a third semiconductor substrate . As shown in FIG. 16 , the first semiconductor substrate 110 is laminated on the second semiconductor substrate 120 , and the second semiconductor substrate 120 is laminated on the third semiconductor substrate 130 .
- the first semiconductor substrate 110 has a pixel portion 101 and a connection region 1601 .
- the pixel unit 101 outputs pixel signals based on incident light.
- a connection region 1601 is arranged around the pixel portion 101 .
- a pair of connection regions 1601 are arranged along two opposite sides of the first semiconductor substrate 110 on the front and back of the pixel portion 101 .
- the second semiconductor substrate 120 has a control circuit section 102 , a peripheral circuit section 121 and a signal processing section 1602 .
- the control circuit unit 102 outputs control signals for controlling driving of the pixel unit 101 to the pixel unit 101 .
- the control circuit section 102 is arranged at a position facing the pixel section 101 on the second semiconductor substrate 120 .
- the peripheral circuit section 121 controls driving of the control circuit section 102 .
- the peripheral circuit section 121 is arranged around the control circuit section 102 on the second semiconductor substrate 120 .
- the peripheral circuit section 121 may be electrically connected to the first semiconductor substrate 110 to control driving of the pixel section 101 .
- the peripheral circuit section 121 is arranged along two opposite sides of the second semiconductor substrate 120, but the arrangement method of the peripheral circuit section 121 is not limited to this example.
- An analog pixel signal output from the first semiconductor substrate 110 is input to the signal processing unit 1602 .
- a signal processing unit 1602 performs signal processing on pixel signals. For example, the signal processing unit 1602 performs processing for converting analog pixel signals into digital signals.
- the signal processing unit 1602 may perform other signal processing. Examples of other signal processing include noise reduction processing such as analog or digital CDS (Correlated Double Sampling).
- the signal processing unit 1602 is arranged around the control circuit unit 102, that is, outside. In the example of FIG. 16 , a pair of signal processing units 1602 are arranged along two sides facing each other of the second semiconductor substrate 120 in front and behind the control circuit unit 102 .
- the signal processing section 1602 may be a circuit included in the peripheral circuit section 121 .
- the third semiconductor substrate 130 has the data processing section 103 .
- the data processing unit 103 uses the digital data output from the second semiconductor substrate 120 to perform addition processing, thinning processing, and other image processing.
- FIG. 17 is an explanatory diagram showing another example of the specific configuration of the control circuit section 102.
- the control block 400B has the pixel control section 401 (autonomous exposure processing section 411, exposure control section 412, pixel driving section 413) but does not have the signal processing section 402.
- FIG. 17 is an explanatory diagram showing another example of the specific configuration of the control circuit section 102.
- the control block 400B has the pixel control section 401 (autonomous exposure processing section 411, exposure control section 412, pixel driving section 413) but does not have the signal processing section 402.
- FIG. pixel control section 401 autonomous exposure processing section 411, exposure control section 412, pixel driving section 413
- one control block 400B may be provided for N pixel blocks 200 (N is a natural number equal to or greater than 2).
- the N pixel blocks 200 corresponding to one pixel block are sometimes called a pixel block group.
- one control block 400B may be provided with two pixel blocks 200 arranged side by side in the column direction as one pixel block group. In this case, the control block 400B may control the exposure time for each pixel block 200.
- FIG. 1 is a natural number equal to or greater than 2.
- control block 400B is electrically connected to at least one pixel block 200 and can be said to be the minimum unit of a circuit that controls exposure of the pixels 201 of the at least one pixel block 200.
- FIG. 18 is an explanatory diagram showing the connection relationship between the first semiconductor substrate 110 and the second semiconductor substrate 120 in the imaging element 100B.
- the first semiconductor substrate 110 includes a connection region 1801 and a connection region 1601 provided around the pixel portion 101 and electrically connected to the pixel portion 101 .
- the second semiconductor substrate 120 includes a connection region 1802 and a connection region 1803 provided around the control circuit section 102 and electrically connected to the control circuit section 102 .
- connection regions 1801 are connected to a pair of connection regions 1802 located at opposite positions.
- a connection region 1801 and a connection region 1802 connected to each other input a control signal from the global driving section 600 to the pixel section 101 using a global control line.
- connection regions 1601 are connected to a pair of connection regions 1803 located at opposite positions.
- the connection region 1601 and the connection region 1803 connected to each other input pixel signals from the pixel unit 101 to the corresponding ADC units 1820 and 1830 using a common signal line.
- FIG. 19 is an explanatory diagram showing an example of signal transmission between the first semiconductor substrate 110 and the second semiconductor substrate 120 in the imaging element 100B.
- the global driver 600 outputs a reset control signal ⁇ RST, a selection control signal ⁇ SEL and a transfer selection control signal ⁇ TXSEL.
- the global driver 600 is connected to reset control lines 1903 and select control lines 1904 that output signals to the respective pixel blocks 200 .
- the global driving section 600 supplies a reset control signal ⁇ RST to the plurality of pixel blocks 200 through a reset control line 1903 and supplies a selection control signal ⁇ SEL through a selection control line 1904 .
- the global driver 600 supplies a transfer selection control signal ⁇ TXSEL to the plurality of control blocks 400B via the transfer selection control line 1905.
- a transfer selection control signal ⁇ TXSEL is supplied from the global driving section 600 to the control block 400B in order to control the exposure time for each pixel block 200.
- the control block 400 B supplied with the transfer selection control signal ⁇ TXSEL outputs the transfer selection control signal ⁇ TXSEL to the corresponding pixel block 200 .
- the pixel block 200 determines whether to input the transfer selection control signal ⁇ TXSEL to the pixel 201 as the transfer control signal ⁇ TX or the discharge control signal ⁇ PDRST. As a result, the input of the transfer control signal ⁇ TX or the discharge control signal ⁇ PDRST to the pixel 201 is skipped.
- the control block 400B extends the exposure time by skipping the transfer control signal ⁇ TX. Further, when the transfer control signal ⁇ TX determines the exposure start time, the control block 400B can shorten the exposure time by skipping the transfer control signal ⁇ TX. Thus, the exposure time of the pixel block 200 can be adjusted by the transfer selection control signal ⁇ TXSEL. The same is true when the discharge control signal ⁇ PDRST determines the start time or end time of exposure.
- the reset control line 1903, the selection control line 1904, and the transfer selection control line 1905 are globally wired, that is, provided commonly to the plurality of pixel blocks 200.
- FIG. A reset control line 1903, a selection control line 1904, and a transfer selection control line 1905 are wired across the pixel portion 101 in the row direction.
- the reset control line 1903, the selection control line 1904, and the transfer selection control line 1905 may be wired across the pixel portion 101 in the column direction.
- the reset control line 1903 is connected to the gate terminal of the reset section 304 of the pixel block 200 and supplies the reset control signal ⁇ RST.
- a selection control line 1904 is connected to the gate terminal of the selection section 352 of the pixel block 200 and supplies a selection control signal ⁇ SEL.
- the transfer selection control line 1905 is connected to each of the plurality of control blocks 400B to supply the pixel control section 401 with a transfer selection control signal ⁇ TXSEL.
- the global driver 600 outputs the transfer selection control signal ⁇ TXSEL from the second semiconductor substrate 120 to the first semiconductor substrate 110
- the transfer selection control signal ⁇ TXSEL is not supplied to the first semiconductor substrate 110 and is sent to the control block 400B.
- ⁇ TXSEL may be output.
- the transfer selection control line 1905 is provided on the second semiconductor substrate 120 .
- the transfer control line 1901a and the discharge control line 1902a are connected to the pixel block 200a.
- the transfer control line 1901a is connected to the gate terminal of the transfer section 301 provided in the pixel block 200a.
- the transfer control line 1901a supplies the transfer control signal ⁇ TX output from the control block 400Ba to the pixel block 200a.
- the discharge control line 1902a is connected to the gate terminal of the discharge section 302 provided in the pixel block 200a.
- the discharge control line 1902a supplies the discharge control signal ⁇ PDRST output from the control block 400Ba to the pixel block 200a.
- the transfer control line 1901b and the discharge control line 1902b are connected to the pixel block 200b.
- the transfer control line 1901b is connected to the gate terminal of the transfer section 301 provided in the pixel block 200b.
- the transfer control line 1901b supplies the transfer control signal ⁇ TX output from the control block 400Bb to the pixel block 200b.
- the discharge control line 1902b is connected to the gate terminal of the discharge section 302 provided in the pixel block 200b.
- the discharge control line 1902b supplies the discharge control signal ⁇ PDRST output from the control block 400Bb to the pixel block 200b.
- a plurality of bonding portions 610 are provided on bonding surfaces where the first semiconductor substrate 110 and the second semiconductor substrate 120 are bonded to each other.
- the bonding portion 610 of the first semiconductor substrate 110 is aligned with the bonding portion 610 of the second semiconductor substrate 120 .
- a plurality of bonding portions 610 that face each other are electrically connected by being bonded by pressure treatment or the like of the first semiconductor substrate 110 and the second semiconductor substrate 120 .
- the global control line junction 610 may be under the corresponding pixel block 200 or in the connection regions 1801 and 1802 .
- the local control line junction 610 is provided below the corresponding pixel block 200 (also above the control block 400B).
- the imaging element 100B controls the exposure time for each pixel block 200 by changing the timing of at least one of the transfer section 301 and the discharge section 302 using local control lines. By combining local control lines and global control lines, the imaging device 100B can realize exposure time control with fewer control lines.
- FIG. 20 is an explanatory diagram showing the connection relationship between the ADC section and the pixel blocks.
- a common signal line 202 extending in the column direction is arranged for each column inside the pixel block 200c. Further, this signal line 202 is also common to a plurality of pixel blocks 200c and 200d arranged in the column direction. Therefore, in this example, one signal line 202 is connected to m ⁇ M pixels 201 arranged in one column, and pixel signals from these pixels 201 are output.
- An ADC 2000 is connected to each of the signal lines 202 on the second semiconductor substrate 120 side via a joint 610 .
- a plurality of ADCs 2000 corresponding to a plurality of signal lines 202 constitute ADC section 1820 .
- the ADC section 1820 is provided with the ADCs 2000 corresponding to the pixel blocks 200c and 200d in the odd columns, and the ADC section 1830 is provided with the ADCs 2000 corresponding to the pixel blocks 200e and 200f in the even columns.
- the arrangement relationship between the pixel block 200c etc. and the corresponding ADC unit 1820 etc. is not limited to this.
- each ADC 2000 converts pixel signals sequentially output from the connected m ⁇ M pixels 201 in one column into digital signals and outputs the digital signals.
- the ADC units 1820 and 1830 as a whole convert pixel signals from the pixels 201 arranged in n ⁇ N columns in the row direction into digital signals in parallel. From this point of view, this digital conversion can be said to be a kind of so-called column ADC. Note that although a single-slope ADC is given as an example of the ADC, other digital conversion methods may be used. Also, the connection position of each pixel 201 and the signal line 202 is not limited to the form shown in FIG. 20, and may be in each pixel block 200c or the like as another example.
- FIG. 21 is a timing chart showing imaging operations in the pixel block 200 of the imaging device 100B. Driving of the pixel block 200 is controlled by a transfer control signal ⁇ TX, a discharge control signal ⁇ PDRST, a reset control signal ⁇ RST and a selection control signal ⁇ SEL.
- the discharge control signal ⁇ PDRST controls the timing of starting exposure.
- the exposure start timing corresponds to the fall timing of the discharge control signal ⁇ PDRST (for example, time T1). That is, before the exposure start time T1, the discharge control signal ⁇ PDRST turns on the discharge unit 302 to discharge the charges accumulated in the photoelectric conversion unit 300, and the exposure starts at the fall of the discharge control signal ⁇ PDRST. do. Since the discharge control signal ⁇ PDRST is locally controlled, the exposure time can be adjusted for each pixel block 200 .
- the transfer control signal ⁇ TX controls the timing of ending exposure.
- the transfer control signal ⁇ TX turns on the transfer unit 301 to transfer the charge accumulated in the photoelectric conversion unit 300 to the FD 303 .
- the end timing of exposure corresponds to the falling timing of the transfer control signal ⁇ TX (for example, time T4).
- the reset control signal ⁇ RST controls the timing of discharge of charges accumulated in the FD 303 .
- the reset control signal ⁇ RST turns on the reset section 304 to discharge the charge of the FD 303 .
- a selection control signal ⁇ SEL is a signal for selecting an arbitrary pixel 201 .
- the selection control signal ⁇ SEL controls on/off of the selection section 352 .
- the selection control signal ⁇ SEL is set high.
- the imaging device 100B can change the exposure start timing for each pixel block 200 and control the exposure time for each pixel block 200 by locally controlling the discharge control signal ⁇ PDRST. Further, the imaging device 100B may control the end timing of exposure for each pixel block 200 by locally controlling the transfer control signal ⁇ TX. The imaging element 100B may control both the start timing and end timing of exposure for each pixel block 200 by locally controlling both the transfer control signal ⁇ TX and the discharge control signal ⁇ PDRST.
- a pixel signal of each pixel 201 corresponds to the charge amount accumulated in the photoelectric conversion unit 300 . Therefore, controlling the timing of exposure of the pixels 201 can be said to control the timing of charge accumulation in the photoelectric conversion unit 300 . More specifically, controlling the timing of exposure of the pixels 201 can be said to control the timing and length of the charge accumulation time from charge discharge to charge transfer.
- FIG. 22 is an explanatory diagram showing an example of exposure timing for each pixel block 200.
- the exposure time is controlled for each of the three pixel blocks 200 arranged in one row.
- the image pickup device 100B changes the exposure amount by shifting the pixel reset time for each pixel block 200 .
- the timing of reading pixel signals is in order from the pixel block 200 on the top. That is, the pixel signal is read from the pixel 201 of "pixel block 1", then the pixel signal is read from the pixel 201 of "pixel block 2", and then the pixel signal is read from the pixel 201 of "pixel block 3".
- the global driving section 600 sets the selection control signal ⁇ SEL to high row by row across the plurality of pixel blocks 200 arranged in one column from the first row to the m ⁇ Mth row.
- a common selection control line 1904 is connected to n ⁇ N pixels arranged in the same row. Therefore, pixel signals are read out in parallel from the n ⁇ N pixels 201 connected to the row in which the selection control signal ⁇ SEL is set to high. Accordingly, pixel signals for one frame can be output.
- pixel signals are digitally converted by ADC units 1820 and 252 as described in FIG.
- the digital-converted pixel signals are output to subsequent image processing to form an image for one frame.
- the readout method of the present embodiment is the so-called rolling shutter method for the entire pixel unit 101. It can also be said that However, even in that case, it is possible to set a different exposure time for each pixel block 200 .
- the imaging device 100B shown in FIGS. 16 to 22 performs exposure in units of pixel blocks 200, but sequentially reads out pixel signals for each pixel row and performs AD conversion for each pixel column. Specifically, the image sensor 100B reads pixel signals from the pixels 201 of the upper pixel block 200 among the plurality of pixel blocks 200 arranged in a row, and then reads the pixel signals from the pixels 201 of the lower pixel block 200. Read out the signal. Therefore, when a moving subject is captured, the distortion of the image due to the readout order is smoothed, and the viewer's discomfort with the image can be reduced.
- the pixel blocks 200 correspond to the vertical direction of the image (that is, the pixel column direction).
- a plurality of saw-toothed steps appear to cause discomfort to the observer.
- the plurality of steps do not appear in the image.
- the image sensor 100B shown in FIGS. 16 to 22 does not include an ADC section for converting analog signals into digital signals in the control block 400B, and the signal processing section 1602 is arranged outside the control circuit section . Therefore, the area of the control block 400B can be reduced, and the size of the pixel block 200 arranged at the position corresponding to the control block 400B can be reduced. can be done. As a result, it is possible to finely control the exposure time within the image, and to make the boundaries of the pixel blocks 200 inconspicuous on the image. Furthermore, since digital conversion is not performed immediately below the pixel 201, the influence of noise on the pixel 201 due to heat generation can be suppressed.
- the signal processing unit 1602 does not have to be provided in a plurality of separate regions, and may be provided in one region for the entire pixel unit 101 .
- the readout method of the image pickup device 100B is also As a whole, it can be said that it is a so-called rolling shutter system.
- different exposure times can be set for each pixel block 200, as in the image sensor 100A.
- the image pickup device 100B similarly to the image pickup device 100A, the image distortion due to the readout order when capturing an image of a moving subject is smoothed, and the viewer's sense of discomfort in the image can be reduced.
- the autonomous exposure processing unit 411 is implemented within the control block 400 as shown in FIGS. Also, the autonomous exposure processing unit 411 can be mounted in the peripheral circuit unit 121 instead of the control block 400, or can be mounted in both the control block 400 and the peripheral circuit unit 121. is. These three patterns will be described below with reference to FIGS. 23 to 25. FIG.
- FIG. 23 is a block diagram showing a configuration example of the autonomous exposure control method 1.
- Autonomous exposure control method 1 is a configuration example in which the autonomous exposure processing unit 411 is implemented in the control block 400 .
- the addition of the autonomous exposure processing unit 411 to the control block 400 increases the circuit scale of the control block 400, but each pixel 201 of the pixel block 200 may increase accordingly, so the light receiving area is increased. Is possible.
- control block 400A will be described as an example (the same applies to FIG. 25).
- the control block 400A has a signal conversion section 422, a signal output section 423, an autonomous exposure processing section 411, an exposure control section 412, and a pixel driving section 413.
- the signal input unit 421 is omitted.
- the signal input section 421, the signal conversion section 422 and the signal output section 423 are not included in the control block 400B, but are arranged on the second semiconductor substrate 120 as the signal processing section 1602 (FIG. 25). as well).
- the signal conversion unit 422 has n ADCs 500 .
- Each of the n ADCs 500 converts analog pixel signals from m pixels 201 connected in the column direction into digital signals.
- the ADC 500 is composed of a comparator 501 and a storage section 502 .
- a column selection circuit 2301 is included in the signal output section 423 .
- the column selection circuit 2301 sequentially selects columns of the pixel block 200 each time a readout column selection signal is input from the external K. Each time a horizontal transfer clock is input from the outside, the column selection circuit 2301 outputs digital pixel signals from the m pixels 201 in the selected column to the peripheral circuit section 121 via the horizontal transfer line 2300. Output to the autonomous exposure processing unit 411 .
- the autonomous exposure processing unit 411 calculates an exposure value indicating the exposure time of the pixel block 200 .
- the autonomous exposure processing section 411 has a preprocessing section 2311 , a controller 2312 , and an exposure value calculation section 2313 .
- a preprocessing unit 2311 acquires a digital pixel signal for each pixel column of the pixel block 200 from the column selection circuit 2301 . Then, the preprocessing unit 2311 calculates a statistical value (for example, average value, median value, maximum value, or minimum value) of the acquired pixel signals. The preprocessing unit 2311 outputs this calculation result to the exposure value calculation unit 2313 .
- a statistical value for example, average value, median value, maximum value, or minimum value
- the controller 2312 inputs a reset signal to the preprocessing unit 2311 to reset preprocessing by the preprocessing unit 2311 .
- the preprocessing unit 2311 calculates the statistic value of the pixel signals from the pixel block 200 each time reset is performed, that is, for each frame.
- the exposure value calculation unit 2313 determines the next exposure value based on the calculation result (statistical value of pixel signals) from the preprocessing unit 2311 . Specifically, for example, the exposure value calculator determines the next exposure value based on the calculation result so as not to cause underexposure or overexposure. For example, exposure value calculator 2313 holds a first threshold value and a second threshold value.
- the first threshold is a threshold for determining whether or not the calculation result is underexposure.
- the second threshold is a threshold larger than the first threshold, and is a threshold for determining whether the calculation result is overexposure.
- the exposure value calculator 2313 determines whether the calculation result is equal to or greater than the first threshold value and equal to or less than the second threshold value. If the calculation result is greater than or equal to the first threshold value and less than or equal to the second threshold value, the exposure value calculation section outputs the calculation result to the latch circuit 2321 of the exposure control section 412 as an exposure value. If the calculation result is less than the first threshold, the exposure value calculator 2313 outputs the first threshold to the latch circuit 2321 of the exposure controller 412 as the exposure value. If the calculation result exceeds the second threshold, the exposure value calculator outputs the second threshold to the latch circuit 2321 of the exposure controller 412 as the exposure value.
- the exposure value calculation unit 2313 may hold a plurality of exposure value ranges. In this case, if the calculation result is greater than or equal to the first threshold value and less than or equal to the second threshold value, the exposure value calculation unit 2313 sets the number of steps in the exposure value range that includes the calculation result as the exposure value, and latches the exposure control unit 412. Output to circuit 2321 .
- the exposure value calculation unit 2313 sets the number of steps that is one or more steps higher than the number of steps in the exposure value range that includes the calculation result as the exposure value of the exposure control unit 412. Output to latch circuit 2321 . Further, if the calculation result exceeds the second threshold, the exposure value calculation unit 2313 sets the number of steps lower than the number of steps of the exposure value range including the calculation result by one step or more as the exposure value. 412 latch circuit 2321.
- the exposure control section 412 has, for example, a latch circuit 2321, a shift register 2322, a pixel block control section, and a level shift section.
- a latch circuit 2321 holds the exposure value from the autonomous exposure processing unit.
- the latch circuit 2321 outputs the held exposure value to the pixel block control section and the shift register 2322 each time a latch pulse is input from the outside.
- the shift register 2322 parallel-serial converts the exposure value from the latch circuit 2321 and outputs it as a serial signal to the data processing section.
- the exposure time is calculated by an external system outside the image pickup device 100 and the calculated result is fed back to the image pickup device 100, it takes time to reflect the exposure time to the image pickup device 100, increasing power consumption.
- the autonomous exposure processing unit 411 in the control block 400 it is possible to improve the reflection speed of the exposure time to the pixel block 200 and reduce the power consumption.
- one pixel block 200 may be sequentially selected from a plurality of pixel blocks 200 in synchronization with , and the exposure value calculated.
- a selector is provided on the output side of the exposure value calculation unit 2313 , and the controller 2312 outputs a selection signal for selecting one pixel block 200 from a plurality of pixel blocks 200 to the selector.
- the exposure control unit 412 has a latch circuit 2321 and a shift register 2322 for each pixel block 200 .
- Each of the latch circuits 2321 is connected to a selector (not shown) in the autonomous exposure processing unit 411, and when an exposure value is input from the selector, the held exposure value is transferred to the pixel block control unit 503 each time a latch pulse is input. and output to the shift register 2322 .
- autonomous exposure can be realized even when exposure control is performed for a plurality of pixel blocks 200 by one control block 400 .
- FIG. 24 is a block diagram showing a configuration example of the autonomous exposure control method 2.
- Autonomous exposure control method 2 is a configuration example in which the autonomous exposure processing unit 411 is implemented in the peripheral circuit unit 121 .
- the autonomous exposure processing section 411 is mounted in the peripheral circuit section 121 instead of within the control block. Therefore, the circuit scale of the control block 400 can be made smaller than in the case of FIG.
- the peripheral circuit section 121 is connected to the pixel section 101 via the horizontal transfer section 2410 .
- the horizontal transfer section 2410 is connected to each pixel block 200 arranged in the row direction (hereinafter referred to as pixel block row), and transfers pixel signals to the peripheral circuit section 121 for each pixel block row. Since the pixel unit 101 is a set of pixel blocks 200 of M rows and N columns, the horizontal transfer unit 2410 transfers pixel signals to the peripheral circuit unit 121 for each M pixel block rows.
- the peripheral circuit section 121 has row-direction autonomous exposure processing section groups 2400-1 to 2400-M for each pixel block row (simply referred to as row-direction autonomous exposure processing section group 2400 when these are not distinguished).
- the data sampling unit 2411 equally divides the pixel signal columns of the pixel block rows from the horizontal transfer unit 2410 into N and samples them.
- the data sampling section 2411 outputs each sampled pixel signal sequence to the corresponding preprocessing section 2311 .
- the preprocessing unit 2311 calculates statistical values of pixel signals from the corresponding pixel block 200 as described above. Further, since the peripheral circuit unit 121 can have a circuit scale larger than that of the control block 400, the preprocessing unit 2311 can execute processing other than the calculation of the statistical value of the pixel signal.
- the preprocessing unit 2311 has a memory for storing the pixel number of the defective pixel in the corresponding pixel block 200 at the time of manufacture, and when the data sampling unit 2411 samples the pixel signal of the pixel number, the preprocessing unit 2311 The unit 2311 is not used for calculating the statistical value of the pixel signal. As a result, it is possible to improve the accuracy of calculating the statistical value of the pixel signal.
- the preprocessing unit 2311 obtains the calculation result from another preprocessing unit 2311 in charge of the pixel block 200 adjacent to the corresponding pixel block 200, and based on the calculation result obtained from the other preprocessing unit 2311, performs the corresponding processing. Statistics of pixel signals from pixel block 200 may be calculated. As a result, the exposure step between adjacent pixel blocks 200 can be smoothed.
- a first threshold value and a second threshold value are set in the exposure value calculation unit 2313, and the first threshold value and the second threshold value are set according to the imaging mode of the imaging apparatus in which the imaging element 100 is mounted. At least one of the second thresholds may be changeable. This makes it possible to calculate the optimum exposure according to the shooting mode.
- the peripheral circuit section 121 has a latch circuit 2321 and a shift register 2322 for each exposure value calculation section 2313 .
- the shift register 2322 parallel-serial converts the exposure value from the latch circuit 2321, outputs the serial signal to the data processing unit 103, Output the exposure value.
- the circuit scale of the control block 400 can be reduced compared to the case of FIG. 23, and the size of the corresponding pixel block 200 can be reduced. Therefore, the number of pixel blocks is increased, and fine autonomous exposure control becomes possible. Also, the exposure control section 412 and the pixel driving section 413 may be mounted in the peripheral circuit section 121 . Thereby, the circuit scale of the control block 400 can be further reduced, and the size of the corresponding pixel block 200 can be reduced.
- FIG. 25 is a block diagram showing a configuration example of the autonomous exposure control method 3.
- Autonomous exposure control method 3 is a configuration example in which the autonomous exposure processing unit 411 is implemented in both the control block 400A and the peripheral circuit unit 121 .
- data transmission such as sending pixel signals from the control block 400A to the peripheral circuit section 121 and sending exposure values from the peripheral circuit section 121 to the pixel block 200 is unnecessary.
- Become. Therefore, the feedback to the corresponding pixel block 200 is faster than when it is executed in the peripheral circuit section 121 .
- the circuit scale of the autonomous exposure processing section 411 is increased by mounting it in the peripheral circuit section 121 rather than mounting it in the control block 400A. can do. For this reason, it is better to implement more advanced functions for autonomous exposure control in the peripheral circuit section 121 (for example, removal of pixel signals of defective pixels described in FIG. 24, exposure step control with the adjacent pixel block 200, Calculation of optimum exposure according to the exposure) can be implemented.
- the imaging device 100 uses the peripheral circuit unit 121 when performing highly functional calculations related to autonomous exposure control, and the control unit 121 when performing feedback of the exposure value at high speed, depending on the situation.
- autonomous exposure control is performed.
- autonomous exposure control is executed by the row direction autonomous exposure processing unit group 2400 in the peripheral circuit unit 121. If given, perform autonomous exposure control for each control block 400A.
- the image pickup device 100 operates in the peripheral circuit unit 121 when high-performance calculation related to autonomous exposure control is selected by user operation, and in the control block 400A when high-speed execution of exposure value feedback is selected. , to perform autonomous exposure control. Further, when the remaining battery level becomes equal to or less than a predetermined amount, the imaging device 100 may select and execute low power consumption processing among high-speed execution of highly functional calculations related to autonomous exposure control and exposure value feedback. good.
- a row-direction autonomous exposure processing unit group 2400 mounted in the peripheral circuit unit 121 has the same configuration as that shown in FIG. 24, so it is omitted in FIG.
- the column selection circuit 2301 outputs n-bit digital pixel signals to n OR circuits 2501 .
- An autonomous exposure processing unit 2500 in the control block 400A has a controller 2312, n OR circuits 2501, an output data latch circuit 2502, and an n-bit AND circuit 2503.
- the controller 2312 inputs a reset signal to the output data latch circuit 2502 when the n-bit signal is output from the output data latch circuit 2502 .
- the OR circuit 2501 is a logic circuit with two inputs and one output. One input of OR circuit 2501 is connected to the column selection circuit and the other input is connected to the output of n-bit AND circuit 2503 .
- the n OR circuits 2501 are connected to the input of the output data latch circuit 2502 .
- Output data latch circuit 2502 holds n-bit signals from n OR circuits 2501 .
- the output data latch circuit 2502 outputs an n-bit signal to the n-bit AND circuit 2503 when the horizontal transfer clock is input. Further, when a reset signal is input from the controller 2312, the output data latch circuit 2502 resets the held n-bit signal, and converts the n-bit signal having at least one bit of 0 out of the n bits to an n-bit AND circuit. 2503 for output.
- the n-bit AND circuit 2503 is an n-input, 1-output AND circuit, and the output of the output data latch circuit 2502 is connected to the input of the n-bit AND circuit 2503 .
- the output of the n-bit AND circuit 2503 is connected to the selector 2512 of the exposure control section 412 and the input of each OR circuit 2501 . If the output from the n-bit AND circuit 2503 is "0", it indicates that the pixel column outputting the n-bit digital pixel signal is not saturated. If the output from the n-bit AND circuit 2503 is "1", it indicates that the pixel column outputting the n-bit digital pixel signal is saturated.
- a 1-bit signal of "1" output from the n-bit AND circuit 2503 is hereinafter referred to as a saturation detection signal.
- each OR circuit 2501 If the value of the digital pixel signal from the pixel 201 in the pixel column is "1", it indicates that the pixel 201 is saturated. If the value of the n-bit signal from the column selection circuit 2301 is all “1”, it indicates that the entire pixel column is saturated. In this case, since "1" is input to one input of each OR circuit 2501, each OR circuit 2501 outputs a 1-bit signal whose value is "1" to the output data latch circuit 2502. FIG.
- the output data latch circuit 2502 holds these n bit signals whose values are all "1", and outputs the held n bit signals to the n bit AND circuit 2503 when the horizontal transfer clock is input. do.
- the n-bit AND circuit 2503 outputs a saturation detection signal with a value of "1" to the selector 2512 and each OR circuit 2501 when an n-bit signal whose value is all "1" is input.
- the output data latch circuit 2502 outputs an n-bit signal whose value is all "1” to the n-bit AND circuit 2503 until the reset signal is input. Therefore, n-bit AND circuit 2503 outputs the saturation detection signal until output data latch circuit 2502 receives a reset signal from controller 2312 .
- the exposure control unit 412 has a shift register 2511 and a selector 2512 in addition to the configuration shown in FIG.
- the shift register 2511 serial-parallel converts the exposure value from the peripheral circuit section 121 and outputs it to the level shift section 504 and the selector 2512 .
- a selector 2512 inputs the exposure value and the set exposure value from the shift register 2511 .
- Selector 2512 selects either the exposure value from shift register 2511 or the set exposure value based on the output signal from n-bit AND circuit 2503 and outputs the selected exposure value to latch circuit 2321 .
- the set exposure value is an exposure value corresponding to an exposure time that does not saturate the pixels 201, for example, an exposure value that is set so that the exposure time is the shortest.
- the set exposure value is calculated and set by an external system outside the control block 400A, for example.
- the set exposure value may be a fixed value or may be selected from an external system.
- the external system is, for example, the peripheral circuit unit 121 in the image pickup device 100, the data processing unit 103 in the third semiconductor substrate 130, or the image processing unit connected to the image pickup device 100 in an image pickup apparatus having the image pickup device 100. be.
- the selector 2512 selects the exposure value from the shift register 2511 and outputs it to the latch circuit 2321 when the output signal from the n-bit AND circuit 2503 is not the saturation detection signal.
- the selector 2512 selects the set exposure value and outputs it to the latch circuit 2321 .
- the autonomous exposure processing unit 2500 and the exposure control unit 412 in the control block 400A perform autonomous exposure control using the exposure value from the peripheral circuit unit 121 until saturation is detected in the control block 400A.
- autonomous exposure control is executed using the set exposure value in the exposure control section 412.
- the autonomous exposure processing section 2500 in the control block 400 may be the autonomous exposure processing section 411 shown in FIG.
- the autonomous exposure processing section 411 in the peripheral circuit section 121 and the autonomous exposure processing section 411 in the control block 400 may be selectable by user setting.
- an imaging device equipped with the imaging device 100 may be made selectable between the autonomous exposure processing unit 411 in the peripheral circuit unit 121 and the autonomous exposure processing unit 411 in the control block 400 based on the remaining battery power.
- the imaging apparatus selects autonomous exposure control by the autonomous exposure processing section 411 in the peripheral circuit section 121 if the remaining battery level is equal to or greater than a predetermined value, and if not equal to or greater than the predetermined value, the autonomous exposure control in the control block 400 is performed. Autonomous exposure control by the exposure processing unit 411 may be selected.
- the user selects the autonomous exposure processing unit 411 in the peripheral circuit unit 121 to perform high-quality imaging, and selects the autonomous exposure processing unit 411 in the control block 400 to reduce power consumption. do it.
- the imaging device 100 can perform exposure control by the control block 400 corresponding to each pixel block 200 .
- the imaging device 100 has a frame skip function that realizes long exposure by skipping control of the transfer control signal ⁇ TX by the transfer selection control signal ⁇ TXSEL.
- the image pickup device 100 is capable of long-time exposure exceeding the exposure time for one frame (1 frame exposure) by the frame skip function, and can also be used for low frame rate operation (60 fps) like live view.
- the control block 400 during frame skipping performs AD conversion for each frame, but does not read the optical signal, and outputs a pseudo signal. By stopping the output operation of the pseudo signal, it is possible to reduce the noise generated by the pseudo signal and to save the power consumption of the control block 400 .
- FIG. 26 is an explanatory diagram showing a circuit configuration example inside the control block 400.
- the control block 400A will be described as an example.
- the signal input section 421, the signal conversion section 422 and the signal output section 423 are not included in the control block 400B, but are arranged on the second semiconductor substrate 120 as the signal processing section 1602 (FIG. 27). to FIG. 29).
- the pixel control unit 401 has a pixel block control unit 503 and a level shift unit 504 within the exposure control unit 412 .
- the level shifter 504 has a level shifter 2601 for each pixel row in the pixel block 200 .
- the pixel driving section 413 has a pixel driver 2602 for each pixel row in the pixel block 200 .
- the pixel block control section 503 outputs the transfer control signal ⁇ TX or the discharge control signal ⁇ PDRST to the level shift section 504 .
- the pixel block control unit 503 outputs the transfer selection control signal ⁇ TXSEL to the level shift unit 504 when the transfer selection control signal ⁇ TXSEL is input from the global drive unit 600 in the peripheral circuit unit 121, that is, when the frame skip operation is performed. do.
- Each level shifter 2601 boosts the transfer control signal ⁇ TX or the discharge control signal ⁇ PDRST to the voltage level of the pixel block 200 and outputs it to the pixel driving section 413 .
- Each level shifter 2601 boosts the transfer selection control signal ⁇ TXSEL to the voltage level of the pixel block 200 and outputs it to the pixel driving section 413 .
- Each pixel driver 2602 shifts the pixels 201 in the pixel column as shown in FIG. 12 based on the transfer control signal ⁇ TX or the discharge control signal ⁇ PDRST from the level shifter 2601 in the same pixel row and the transfer selection control signal ⁇ TXSEL. Drive control.
- Counter latches 502 Digital pixel signals from each of the counter latches (hereinafter referred to as counter latches 502 ), which is an example of the storage unit 502 , are held in the SRAM 2604 for each pixel column in the signal output unit 423 and horizontally transferred by the column selection circuit 2401 . It is output to the peripheral circuit section 121 via the line 2300 and output to the autonomous exposure processing section 411 .
- Any one level shifter 2601 (for example, level shifter 2601A) is connected to the load current source 306 for each pixel column in the pixel block 200 via an inverter 2610 .
- This level shifter 2601A outputs an inverted signal ⁇ TXSEL_N of the boosted transfer selection control signal ⁇ TXSEL to each load current source 306 in order to stop the circuit operation of the load current source 306 for each pixel column in the pixel block 200 (FIG. 27). later.).
- this level shifter 2601A is connected to an ADC current source 2603 for each pixel column in the pixel block 200 via an inverter 2610 .
- the level shifter 2601A outputs an inverted signal ⁇ TXSEL_N of the boosted transfer selection control signal ⁇ TXSEL to each ADC current source 2603 in order to stop the circuit operation of the ADC current source 2603 for each pixel column in the pixel block 200 (FIG. 28). later.).
- the pixel block control unit 503 is connected to each counter latch 502 .
- the pixel block control unit 503 outputs a transfer selection control signal ⁇ TXSEL to each counter latch 502 in order to stop the circuit operation of the counter latch 502 for each pixel column in the pixel block 200 (described later in FIG. 29).
- FIG. 27 is an explanatory diagram showing an example 1 of stopping circuit operation in units of control blocks 400. As shown in FIG. Example 1 of stopping circuit operation in units of control blocks 400 is an example of stopping circuit operation of the load current source 306 for each pixel column.
- the signal input section 421 has a load current source 306 and an adjustment section 2700 for each pixel column of the pixel block 200 .
- the load current source 306 is composed of, for example, an n-type MOS transistor, and supplies the signal line 202 with a bias current input from the gate terminal.
- the adjustment unit 2700 is configured with, for example, an n-type MOS transistor, and adjusts the current supplied from the load current source 306 to the pixel column.
- a gate terminal of the adjustment section 2700 is connected to a level shifter 2601A in the pixel control section 401 via an inverter 2610 .
- Inverter 2610 outputs inverted signal ⁇ TXSEL_N when transfer selection control signal ⁇ TXSEL indicating a frame skip operation is output from level shifter 2601A.
- the peripheral circuit section 121 has a pixel current bias circuit 2701 .
- a pixel current bias circuit 2701 is connected to the gate terminal of the load current source 306 for each pixel column in the pixel block 200 and supplies a bias current.
- the load current source 306 thereby supplies the bias current to the signal line 202 .
- the pixel control unit 401 controls the current supply to the pixel columns by the load current source 306 according to the transfer selection control signal ⁇ TXSEL from the level shifter 2601A. Specifically, the pixel control unit 401 controls connection between the pixel column and the load current source 306 . For example, when the transfer selection control signal ⁇ TXSEL is input to the gate terminal of the adjustment unit 2700, the current value of the adjustment unit 2700 becomes larger than when the inverted signal ⁇ TXSEL_N is input, and the pixel columns and the load current source 306 are connected (ON state), and a current is supplied from the load current source 306 to the pixel column.
- the inversion signal ⁇ TXSEL_N is input to the gate terminal of the adjustment unit 2700
- the current value of the adjustment unit 2700 becomes smaller than when the transfer selection control signal ⁇ TXSEL is input. is disconnected (OFF state), and the current supply from the load current source 306 to the pixel column is stopped.
- the power consumption of the load current source 306 can be reduced for each control block 400 . Further, by stopping the current supply from the load current source 306 to the pixel column during frame skipping, the pseudo signal from the pixel 201 is not output. Therefore, a pseudo signal is not superimposed on the output image data, and noise can be reduced.
- FIG. 28 is an explanatory diagram showing Example 2 of circuit operation stop in units of control blocks 400.
- Example 2 of stopping the circuit operation in units of control blocks 400 is an example of stopping the circuit operation of the comparator 501 for each pixel column.
- the ADC current source 2603 for each pixel column of the pixel block 200 has an ADC current source 2603 and an adjustment section 2800 .
- ADC current source 2603 is composed of, for example, an n-channel MOSFET, and supplies bias current input from the gate terminal to comparator 501 .
- the adjustment unit 2800 is configured with, for example, an n-channel MOSFET and adjusts the current supplied from the ADC current source 2603 to the comparator 501 .
- a gate terminal of the adjustment section 2800 is connected to a level shifter 2601A in the pixel control section 401 via an inverter 2610 .
- the peripheral circuit section 121 has an ADC current bias circuit 2801 .
- ADC current bias circuit 2801 is connected to the gate terminal of ADC current source 2603 and provides a bias current. This causes ADC current source 2603 to supply a bias current to comparator 501 .
- the pixel control unit 401 controls current supply from the ADC current source 2603 to the comparator 501 by the transfer selection control signal ⁇ TXSEL from the level shifter 2601A. Specifically, the pixel control unit 401 controls connection between the comparator 501 and the ADC current source 2603 . For example, when the transfer selection control signal ⁇ TXSEL is input to the gate terminal of the adjustment unit 2800, the current value of the adjustment unit 2800 becomes larger than when the inverted signal ⁇ TXSEL_N is input, and the comparator 501 and the ADC current source 2603 are connected (ON state), and a current is supplied from the ADC current source 2603 to the comparator 501 .
- the power consumption of the load current source 306 can be reduced for each control block 400 . Further, by stopping current supply from the ADC current source 2603 to the comparator 501 during frame skipping, no pseudo signal is output from the pixel 201 . Therefore, a pseudo signal is not superimposed on the output image data, and noise can be reduced.
- FIG. 29 is an explanatory diagram showing Example 3 of circuit operation stop in units of control blocks 400.
- Example 3 of stopping the circuit operation for each control block 400 is an example of stopping the circuit operation of the counter latch 502 for each pixel column.
- the control block 400A has a NAND circuit 2901, an inverter 2902 and a transfer circuit 2903 between the comparator 501 and the counter latch 502 in the ADC 500 of the signal line 202 for each pixel column.
- a NAND circuit 2901 receives the output signal from the comparator 501 .
- the NAND circuit 2901 receives an inverted signal ⁇ TXSEL_N obtained by inverting the transfer selection control signal ⁇ TXSEL from the pixel block control unit 503 by the inverter 2900 .
- Transfer selection control signal ⁇ TXSEL serves as an enable signal for controlling the output of NAND circuit 2901 .
- Inverter 2902 inverts the output signal from NAND circuit 2901 and outputs an inverted signal.
- the transfer circuit 2903 has a circuit configuration in which an n-type MOS transistor and a p-type MOS transistor are connected in parallel. Also, the transfer circuit 2903 connects between the ADC counter signal generation section 2904 of the peripheral circuit section 121 and the counter latch 502 .
- the ADC counter signal generation section 2904 outputs the ADC counter signal 2905 to the counter latch 502 .
- the counter latch 502 holds the digital pixel signal according to the ADC counter signal 2905 and outputs it to the SRAM 2604 .
- Transfer circuit 2903 supplies or stops supplying ADC counter signal 2905 to counter latch 502 based on the output value of inverter 2902 .
- FIG. 30 is a truth table of the NAND circuit 2901.
- FIG. 30 When the output value of NAND circuit 2901 is "0", the output value of inverter 2902 becomes “1", and transfer circuit 2903 keeps the output of counter latch 502 until the output value of inverter 2902 is inverted to "0". It feeds the ADC counter signal 2905 .
- the counter latch 502 operates (transfers to the SRAM 2404 ) or stops (holds in the counter latch 502 ) depending on the output of the comparator 501 .
- the enable signal transfer selection control signal ⁇ TXSEL
- the counter latch 502 stops operating (holds in the counter latch 502) regardless of the output of the comparator 501 .
- power consumption can be reduced by stopping the circuit operation when pixel signals are not read.
- power consumption can be reduced by stopping the current of the control block 400 during the exposure time exceeding one frame exposure.
- the exposure time is within one frame exposure, in the case of so-called “window readout" in which only the target pixel block 200 is read out, by stopping the current of the control block 400 that controls the non-target pixel block 200, Low power consumption can be achieved.
- each control block 400 executes a frame skip operation and circuit operation stop for the corresponding pixel block 200 when the transfer selection control signal ⁇ TXSEL is input.
- the transfer selection control signal ⁇ TXSEL is input to the plurality of control blocks 400 in the same block row at the same timing. Therefore, for a plurality of pixel blocks 200 in the same corresponding block row, the frame skip operation and circuit operation stop are performed collectively.
- FIG. 31 is a block diagram showing a configuration example of an imaging device 3100 according to the embodiment.
- the image capturing apparatus 3100 includes an image sensor 100, a system control unit 3101, a driving unit 3102, a photometry unit 3103, a work memory 3104, a recording unit 3105, a display unit 3106, an operation unit 3108, and a driving unit 3114. , and a photographing lens 3120 .
- the photographing lens 3120 guides the subject light flux incident along the optical axis OA to the image sensor 100 .
- the photographing lens 3120 is composed of a plurality of optical lens groups, and forms an image of subject light flux from a scene in the vicinity of its focal plane.
- the imaging lens 3120 may be an interchangeable lens that can be attached to and detached from the imaging device 3100 .
- one virtual lens arranged near the pupil represents the photographing lens 3120 .
- a driving unit 3114 drives a photographing lens 3120 .
- the driving section 3114 moves the optical lens group of the photographing lens 3120 to change the focus position.
- the driving section 3114 may drive the iris diaphragm in the photographing lens 3120 to control the light amount of the subject light flux incident on the imaging device 100 .
- the drive unit 3102 has a control circuit that executes charge accumulation control such as timing control and area control of the image sensor 100 according to instructions from the system control unit 3101 .
- the operation unit 3108 also receives instructions from the photographer using a release button or the like.
- the imaging device 100 delivers the pixel signal to the image processing section 3111 of the system control section 3101 .
- the image processing unit 3111 generates image data by performing various image processing using the work memory 3104 as a work space. For example, when generating image data in the JPEG file format, compression processing is performed after generating a color video signal from the signal obtained in the Bayer array.
- the generated image data is recorded in the recording unit 3105, converted into a display signal, and displayed on the display unit 3106 for a preset time.
- the photometry unit 3103 detects the luminance distribution of the scene prior to a series of shooting sequences for generating image data.
- a photometry unit 3103 includes an AE sensor of about one million pixels, for example.
- a calculation unit 3112 of the system control unit 3101 receives the output of the photometry unit 3103 and calculates the brightness for each area of the scene.
- the calculation unit 3112 determines the shutter speed, aperture value, and ISO sensitivity according to the calculated luminance distribution.
- the photometry unit 3103 may also be used by the image sensor 100 . Note that the calculation unit 3112 also executes various calculations for operating the imaging device 3100 .
- the drive unit 3102 may be partially or wholly mounted on the image sensor 100 . A part of the system control unit 3101 may be mounted on the imaging device 100 .
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Abstract
Description
まず、図1~図22を用いて、撮像素子の構成について説明する。撮像素子の構造は、裏面照射型であっても、表面照射型であってもよい。
つぎに、上述した自律露光処理部411の詳細について説明する。なお、以降の説明において、撮像素子100A、100Bを区別しない場合は、撮像素子100と表記し、制御ブロック400A、400Bを区別しない場合は、制御ブロック400と表記する。
つぎに、制御ブロック400単位での回路動作停止について説明する。以降の説明において、撮像素子100A、100Bを区別しない場合は、撮像素子100と表記し、制御ブロック400A、400Bを区別しない場合は、制御ブロック400と表記する。
図27は、制御ブロック400単位での回路動作停止例1を示す説明図である。制御ブロック400単位での回路動作停止例1は、画素列ごとの負荷電流源306の回路動作停止例である。
図28は、制御ブロック400単位での回路動作停止例2を示す説明図である。制御ブロック400単位での回路動作停止例2は、画素列ごとのコンパレータ501の回路動作停止例である。
図29は、制御ブロック400単位での回路動作停止例3を示す説明図である。制御ブロック400単位での回路動作停止例3は、画素列ごとのカウンタラッチ502の回路動作停止例である。
Claims (29)
- 行方向に並んで配置される複数の画素を有する第1半導体基板と、
前記複数の画素のうち第1画素に電流を供給する第1負荷電流源と、前記複数の画素のうち第2画素に電流を供給する第2負荷電流源と、前記第1負荷電流源による前記第1画素への電流供給を制御する第1画素制御部と、前記第2負荷電流源による前記第2画素への電流供給を制御する第2画素制御部とを有する第2半導体基板と、
を備える撮像素子。 - 請求項1に記載の撮像素子において、
前記第1画素制御部は、前記第1画素と前記第1負荷電流源との間の接続を制御し、
前記第2画素制御部は、前記第2画素と前記第2負荷電流源との間の接続を制御する、
撮像素子。 - 請求項1に記載の撮像素子において、
前記第1負荷電流源により前記第1画素に供給される電流を調整する第1調整部と、
前記第2負荷電流源により前記第2画素に供給される電流を調整する第2調整部と、を備え、
前記第1画素制御部は、前記第1調整部を制御し、
前記第2画素制御部は、前記第2調整部を制御する、
撮像素子。 - 請求項3に記載の撮像素子において、
前記第1調整部は、前記第1画素制御部からの信号に基づいて、前記第1負荷電流源により前記第1画素に供給される電流を調整し、
前記第2調整部は、前記第2画素制御部からの信号に基づいて、前記第2負荷電流源により前記第2画素に供給される電流を調整する、
撮像素子。 - 請求項3または請求項4に記載の撮像素子において、
前記第1調整部は、前記第1画素と前記第1負荷電流源とに接続され、
前記第2調整部は、前記第2画素と前記第2負荷電流源とに接続される、
撮像素子。 - 請求項1から請求項5のいずれか一項に記載の撮像素子において、
前記第1画素から読み出された第1信号をデジタル信号に変換するための第1変換部と、
前記第2画素から読み出された第2信号をデジタル信号に変換するための第2変換部と、
を備える撮像素子。 - 請求項6に記載の撮像素子において、
前記第1画素制御部は、前記第1変換部への電流供給を制御し、
前記第2画素制御部は、前記第2変換部への電流供給を制御する、
撮像素子。 - 請求項6または請求項7に記載の撮像素子において、
前記第1変換部は、前記第1信号が入力される第1比較器を有し、
前記第2変換部は、前記第2信号が入力される第2比較器を有し、
前記第1画素制御部は、前記第1比較器への電流供給を制御し、
前記第2画素制御部は、前記第2比較器への電流供給を制御する、
撮像素子。 - 請求項6から請求項8のいずれか一項に記載の撮像素子において、
前記第1変換部は、第1クロック信号が入力される第1ラッチ回路を有し、
前記第2変換部は、第2クロック信号が入力される第2ラッチ回路を有し、
前記第1画素制御部は、前記第1ラッチ回路への前記第1クロック信号の入力を制御し、
前記第2画素制御部は、前記第2ラッチ回路への前記第2クロック信号の入力を制御する、
撮像素子。 - 請求項1から請求項9のいずれか一項に記載の撮像素子において、
前記第1画素は、光を電荷に変換する第1光電変換部を有し、
前記第2画素は、光を電荷に変換する第2光電変換部を有し、
前記第1画素制御部は、前記第1光電変換部で変換された電荷を蓄積する蓄積時間を制御する制御信号に基づいて、前記第1画素への電流供給を制御し、
前記第2画素制御部は、前記第2光電変換部で変換された電荷を蓄積する蓄積時間を制御する制御信号に基づいて、前記第2画素への電流供給を制御する、
撮像素子。 - 請求項10に記載の撮像素子において、
前記第1画素は、前記第1光電変換部で変換された電荷を転送する第1転送部を有し、
前記第2画素は、前記第2光電変換部で変換された電荷を転送する第2転送部を有し、
前記第1画素制御部は、前記第1転送部を制御する制御信号に基づいて、前記第1画素への電流供給を制御し、
前記第2画素制御部は、前記第2転送部を制御する制御信号に基づいて、前記第2画素への電流供給を制御する、
撮像素子。 - 請求項11に記載の撮像素子において、
前記第1転送部は、前記第1光電変換部で変換された電荷を転送するための第1転送制御信号が出力される第1転送制御線に接続され、
前記第2転送部は、前記第2光電変換部で変換された電荷を転送するための第2転送制御信号が出力される第2転送制御線に接続される、
撮像素子。 - 請求項12に記載の撮像素子において、
前記第1転送制御信号は、前記第1画素制御部から出力され、
前記第2転送制御信号は、前記第2画素制御部から出力される、
撮像素子。 - 請求項10から請求項13のいずれか一項に記載の撮像素子において、
前記第1画素は、前記第1光電変換部の電荷を排出する第1排出部を有し、
前記第2画素は、前記第2光電変換部の電荷を排出する第2排出部を有し、
前記第1画素制御部は、前記第1排出部を制御する制御信号に基づいて、前記第1画素への電流供給を制御し、
前記第2画素制御部は、前記第2排出部を制御する制御信号に基づいて、前記第2画素への電流供給を制御する、
撮像素子。 - 請求項14に記載の撮像素子において、
前記第1排出部は、前記第1光電変換部の電荷を排出するための第1排出制御信号が出力される第1排出制御線に接続され、
前記第2排出部は、前記第2光電変換部の電荷を排出するための第2排出制御信号が出力される第2排出制御線に接続される、
撮像素子。 - 請求項15に記載の撮像素子において、
前記第1排出制御信号は、前記第1画素制御部から出力され、
前記第2排出制御信号は、前記第2画素制御部から出力される、
撮像素子。 - 請求項1から請求項16のいずれか一項に記載の撮像素子において、
前記第1画素は、前記第1半導体基板において第1画素ブロックに配置され、
前記第2画素は、前記第1半導体基板において第2画素ブロックに配置され、
前記第1画素制御部は、前記第2半導体基板において第1制御ブロックに配置され、
前記第2画素制御部は、前記第2半導体基板において第2制御ブロックに配置され、
前記第1画素ブロックと前記第1制御ブロックとは、互いに対向し、
前記第2画素ブロックと前記第2制御ブロックとは、互いに対向する、
撮像素子。 - 請求項1から請求項17のいずれか一項に記載の撮像素子を備える撮像装置。
- 少なくとも1つの画素を含む複数の画素ブロックを有する第1半導体基板と、
前記画素ブロック毎に配置される制御ブロックを有する第2半導体基板と、を備え、
前記制御ブロックは、前記複数の画素ブロックのうち対応する画素ブロックに含まれる前記画素に電流を供給する負荷電流源を制御する画素制御部を有する、
撮像素子。 - 請求項19に記載の撮像素子において、
前記制御ブロックは、前記複数の画素ブロックのうち、対応する画素ブロックに含まれる前記画素から読み出された信号をデジタル信号に変換する変換部を有する、
撮像素子。 - 請求項19に記載の撮像素子において、
前記第2半導体基板は、前記画素から読み出された信号をデジタル信号に変換する変換部を有し、
前記変換部は、前記第2半導体基板において前記複数の制御ブロックが配置される制御回路部の外側に配置される撮像素子。 - 請求項19から請求項21のいずれか一項に記載の撮像素子において、
前記画素制御部は、前記複数の画素ブロックのうち対応する画素ブロックに含まれる前記画素と、前記複数の画素ブロックのうち対応する画素ブロックに含まれる前記画素に電流を供給する負荷電流源との間の接続を制御する、
撮像素子。 - 請求項19から請求項22のいずれか一項に記載の撮像素子において、
前記画素は、光を電荷に変換する光電変換部を有し、
前記画素制御部は、前記光電変換部で変換された電荷を蓄積する蓄積時間を制御する制御信号に基づいて、前記画素への電流供給を制御する、
撮像素子。 - 請求項23に記載の撮像素子において、
前記画素は、前記光電変換部で変換された電荷を転送する転送部を有し、
前記画素制御部は、前記転送部を制御する制御信号に基づいて、前記画素への電流供給を制御する、
撮像素子。 - 請求項24に記載の撮像素子において、
前記転送部は、前記光電変換部で変換された電荷を転送するための転送制御信号が出力される転送制御線に接続され、
前記転送制御信号は、前記画素制御部から出力される、
撮像素子。 - 請求項23から請求項25のいずれか一項に記載の撮像素子において、
前記画素は、前記光電変換部の電荷を排出する排出部を有し、
前記画素制御部は、前記排出部を制御する制御信号に基づいて、前記画素への電流供給を制御する、
撮像素子。 - 請求項26に記載の撮像素子において、
前記排出部は、前記光電変換部の電荷を排出するための排出制御信号が出力される排出制御線に接続される、
撮像素子。 - 請求項27に記載の撮像素子において、
前記排出制御信号は、前記画素制御部から出力される、
撮像素子。 - 請求項19から請求項28のいずれか一項に記載の撮像素子を備える撮像装置。
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JP2013162148A (ja) | 2012-02-01 | 2013-08-19 | Sony Corp | 個体撮像装置および駆動方法、並びに電子機器 |
JP2015126043A (ja) * | 2013-12-26 | 2015-07-06 | ソニー株式会社 | 電子デバイス |
JP2020053782A (ja) * | 2018-09-26 | 2020-04-02 | ソニーセミコンダクタソリューションズ株式会社 | 固体撮像素子、および、撮像装置 |
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