JP2012235193A - Image sensor, imaging device, control method therefor, and control program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a stable black level reference value by reducing the influence of light emission of an amplifier in an OB area while suppressing an increase in a circuit scale.SOLUTION: An OB pixel area and an effective pixel area are specified in a pixel area. A pixel has a charge holding unit 202 in at least part of the OB pixel area. In an accumulation period in which an electric charge is accumulated in an image sensor, an electric charge is transferred from a PD 201 to the charge holding unit in the OB pixel area.

Description

  The present invention relates to an imaging device used in an imaging device such as a digital camera, and more particularly to an imaging device using a solid-state imaging device such as a CMOS image sensor or a CCD, a control method thereof, and a control program.

  In general, in an imaging apparatus such as a digital camera or a video camera, a solid-state imaging element such as a CMOS image sensor is used. In a general CMOS solid-state imaging device, each pixel (unit pixel) includes a photodiode, a floating diffusion (FD) region, a transfer transistor, and an amplifying unit. Then, charges are transferred from the photodiode to the FD region by the transfer transistor, and the charge transferred to the FD region is amplified by the amplifying unit.

  Conventionally, in a solid-state imaging device, a signal in a shaded pixel (optical black or OB) region is output as a reference (reference signal) of an output signal. In the imaging device, a processing circuit that processes the output signal (pixel signal) generates a predetermined black level reference value according to the output of the OB pixel and clamps the output of the effective pixel with the black level reference value. Do.

  Incidentally, in recent years, as the number of pixels of a solid-state image sensor has increased, it has been required to increase the readout speed of pixel signals. For this purpose, it is necessary to increase the speed of the read amplifier. Usually, when the speed of the read amplifier is increased, the power consumption increases as the bias current increases. When the power consumption in the read amplifier increases, the read amplifier may emit light.

  When the readout amplifier emits light, light inevitably leaks into the pixels arranged near the readout amplifier. If light leaks into the OB pixel, the black level reference value shifts, and the output of the effective pixel region is clamped at the wrong black level reference value, thereby degrading the image.

  On the other hand, in order to expand the dynamic range in a solid-state imaging device, there is a device that includes a charge holding unit in a pixel and holds a signal charge output from a photodiode by the charge holding unit (for example, Patent Documents). 1 and 2). If the signal charge is held in the charge holding portion, it is possible to prevent the charge generated in the photodiode due to the light emission of the read amplifier from being added to the signal charge.

JP 2006-217410 A JP 2006-262387 A

  However, Patent Documents 1 and 2 have a problem in that each pixel of the individual imaging device has the same structure and a charge holding unit is provided in each pixel, so that the circuit scale increases.

  Accordingly, an object of the present invention is to provide an imaging device, an imaging apparatus, a control method thereof, and a control capable of obtaining a stable black level reference value by suppressing an increase in circuit scale and reducing the influence of amplifier light emission in the OB region. To provide a program.

  In order to achieve the above object, an image pickup device according to the present invention has a pixel region in which a plurality of pixels are arranged in a two-dimensional matrix, and the pixel region includes a light-shielded pixel region in which the pixel is shielded from light and the pixel Is an image sensor in which an effective pixel region that is not shielded is defined, and a first photoelectric conversion unit that generates a charge corresponding to light, and a charge that is accumulated in the first photoelectric conversion unit And a first floating diffusion part to which the charge accumulated in the charge holding part is transferred, and amplifies the charge accumulated in the first floating diffusion part to thereby form a first pixel A first pixel that outputs a signal; a second photoelectric conversion unit that generates a charge according to light; a second floating diffusion unit to which the charge accumulated in the second photoelectric conversion unit is transferred; And a second pixel that amplifies the charge accumulated in the second floating diffusion portion and outputs it as a second pixel signal, and the first pixel is used as the pixel in at least a part of the light-shielding pixel region. In the effective pixel region, the second pixel is used as the pixel, and the first photoelectric conversion is performed during the accumulation period in which charges are accumulated in the second photoelectric conversion unit. The charge is transferred from the portion to the charge holding portion.

  According to the imaging device of the present invention, the black level of the pixel signal output from the effective pixel region is set according to a difference between the image sensor and the pixel signal output from the first pixel and a black level reference value. And correction means for adjusting to the black level reference value.

  According to the control method of the present invention, when reading out a pixel signal from the image sensor, a first step of storing charges in the first and second photoelectric conversion units, and the first step during the charge storage period. A second step of transferring the charge from the photoelectric conversion unit to the charge holding unit, and when the accumulation of the charge is completed in the second photoelectric conversion unit, the charge accumulated in the second photoelectric conversion unit is And a third step of transferring the charge held in the charge holding portion to the first floating diffusion portion while transferring to the second floating diffusion portion.

  A control program according to the present invention is a control program for reading out a pixel signal from the above-described image sensor, wherein the first step of storing charges in the computer by the first and second photoelectric conversion units; A second step of transferring the charge from the first photoelectric conversion unit to the charge holding unit during a charge accumulation period; and when the accumulation of the charge is completed in the second photoelectric conversion unit, A third step of transferring the charge accumulated in the photoelectric conversion unit to the second floating diffusion unit and transferring the charge held in the charge holding unit to the first floating diffusion unit. It is characterized by.

  According to the present invention, since the pixel signal in the light-shielded pixel region is held by the charge holding unit during the readout period, the influence of the amplifier light emission is reduced, and the black level reference value can be obtained stably. Furthermore, since the charge holding portion is provided only in the pixel in at least a part of the light-shielding pixel region, there is an effect that an increase in circuit scale can be suppressed.

It is a figure which shows roughly the structure of the CMOS image sensor which is an example of the solid-state image sensor by 1st Embodiment by this invention. 2A and 2B are diagrams for explaining a circuit configuration of the image pickup device illustrated in FIG. 1, in which FIG. 1A is a diagram illustrating a circuit configuration of a unit pixel in a right HOB region, and FIG. 2B is a left HOB region, a VOB region, and an effective portion; It is a figure which shows the circuit structure of each unit pixel. FIG. 3 is a plan view schematically showing an example of the layout of the solid-state imaging device described in FIG. 2, (a) showing a first pixel, and (b) showing a second pixel. 3 is a timing chart for explaining an example of the operation of the solid-state imaging device shown in FIG. 1. It is a figure for demonstrating the operation | movement concept of the solid-state image sensor shown in FIG. FIG. 4 is a plan view schematically showing another example of the layout of the solid-state imaging device described in FIG. 2, (a) showing the first pixel, and (b) showing the second pixel. is there. It is a block diagram which shows an example of the imaging device using the solid-state image sensor demonstrated in FIG. It is a block diagram which shows the structure of the analog front end (AFE) shown in FIG. It is a block diagram for demonstrating the pattern noise correction | amendment performed by the image process part shown in FIG.

  Hereinafter, an example of a solid-state imaging device according to an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is a diagram schematically showing a configuration of a CMOS image sensor which is an example of a solid-state image sensor according to the first embodiment of the present invention.

  In FIG. 1, a CMOS image sensor (hereinafter simply referred to as an image sensor) has a pixel region in which a plurality of pixels are arranged in a two-dimensional matrix. In the pixel area, a light-shielded pixel area where the pixels are shielded from light and an effective pixel area (effective portion) where the pixels are not shielded from light are defined.

  As shown, the light-shielding pixel region has horizontal optical black regions 11 and 12 and a vertical optical black (VOB) region 13. Hereinafter, in FIG. 1, the horizontal optical black area 11 located on the left side is called a left HOB area 11, and the horizontal optical black area 12 located on the right side is called a right HOB area 12. In each of the left HOB area 11 and the right HOB area 12, pixels are shielded from light.

  Further, the pixels are also shielded from light in the VOB region 13. The effective portion (effective pixel area) 14 is a pixel area where the pixels are not shielded as described above. A readout amplifier 15 is arranged in the vicinity of the right HOB region 12 outside these pixel regions.

  FIG. 2 is a diagram for explaining a circuit configuration of the image sensor shown in FIG. 1. 2A is a diagram showing a circuit configuration of a unit pixel in the right HOB area 12, and FIG. 2B is a circuit of a unit pixel in each of the left HOB area 11, the VOB area 13, and the effective portion 14. It is a figure which shows a structure.

  In FIG. 2A, a unit pixel (hereinafter referred to as a first pixel) in the right HOB region 12 includes a photodiode (PD) 201 (first photoelectric conversion unit), and the PD 201 receives light. Convert light into electric charge. The charge holding unit 202 temporarily accumulates charges generated in the photodiode 201.

  The illustrated first pixel has a floating diffusion portion (FD) 203 (first floating diffusion portion), and the charge holding portion 202 is connected to PD 201 and FD 203 via transfer switches (Tx) 204 and 205, respectively. Yes. Each of Tx 204 and 205 is formed of a MOS transistor.

  Further, the first pixel includes reset switches (Tres) 206 and 207 configured by MOS transistors and a source follower MOS transistor (Tsf) 208, and Tsf 208 amplifies the voltage (output voltage) of the FD 203. The first pixels are arranged in a matrix (two-dimensional matrix) in the right HOB region, and the first pixels in the same column are connected to a common vertical output line 210 via a selection switch (Tsel) 209. Connected to.

  In the first pixel, when Tres 206 is turned on, the PD 201 is connected to the common power supply VDD 211 to reset the accumulated charge. When Tres 207 is turned ON, the FD 203 is short-circuited with the common power supply VDD 211 and reset to a predetermined potential.

  In FIG. 2B, each unit pixel (hereinafter referred to as a second pixel) of the left HOB 11, VOB 13, and effective unit 14 includes the charge holding unit 202, Tx 204, and Tres 206 included in the first pixel. Not done. Other components are the same as those of the first pixel. That is, in the example shown in FIG. 2, only the right HOB region 12 located in the vicinity of the read amplifier 15 shown in FIG.

  FIG. 3 is a plan view schematically showing an example of the layout of the solid-state imaging device described in FIG. FIG. 3A shows the first pixel, and FIG. 3B shows the second pixel.

  In FIG. 3A, in the first pixel, a Tx 204 is arranged between the PD 201 and the charge holding unit 202, a Tx 205 is arranged on the right side of the charge holding unit 202, and an FD 203 is arranged on the right side thereof. Further, Tres 206 is arranged on the left side of the PD 201. In addition, the area | region shown with the code | symbol 301 in Fig.3 (a) is an area | region where Tres207, Tsf208, and Tsel209 are arrange | positioned. The upper portion of the charge holding unit 202 is shielded from light so that light does not leak from the outside.

  In FIG. 3B, in the second pixel, the Tx 205 and the region 301 are arranged on the right side of the PD 201 (second photoelectric conversion unit), and the FD 203 (second floating diffusion unit) is arranged on the right side of the Tx 205. Yes. Since the second pixel does not include the charge holding unit 202, Tx 204, and Tres 206, the size of the pixel can be made smaller than that of the first pixel.

  Here, the operation of the solid-state imaging device shown in FIG. 1 will be described.

  FIG. 4 is a timing chart for explaining an example of the operation of the solid-state imaging device shown in FIG.

  1, 2, and 4, here, Tsel 209, Tres 206, Tres 207, Tx 204, and Tx 205 are controlled, and the photoelectric conversion result obtained by the photodiode 201 is obtained from the first and second pixels. The charged charges are output as a first pixel signal and a second pixel signal, respectively.

  First, Tres206, Tres207, Tx204, and Tx205 are turned ON in a period T41. As a result, in the first pixel, the potentials of the FD 203 and the charge holding unit 202 are reset to the potential of the common power supply VDD. On the other hand, in the second pixel, by turning on Tres 207 and Tx 205, the potential of the FD 203 is reset to the potential of the common power supply VDD. Thereafter, Tres 206, Tx 204, and Tx 205 are turned off, and the reset operation in the first and second pixels is completed.

  Subsequently, in the period T42, charges are accumulated in the PD 201 in the first and second pixels. In a period T43, Tx204 is turned on, and the charge generated in the PD 201 in the first pixel is transferred to the charge holding unit 202. In order to transfer all charges of the PD 201 to the charge holding unit 202, the channel potential of the charge holding unit 202 is designed to be higher than the channel potential of the PD 201. Here, the charge is an electron.

  Thereafter, Tx204 is turned off again in period T43, and the transfer operation in the first pixel is completed. Then, Tres206 is turned ON in period T43, and PD201 is reset. In the period T43, the charge accumulation state of the PD 201 is maintained in the second pixel.

  Next, in a period T44, pixel signal reading processing is performed. First, Tres 207 is turned off and Tsel 209 is turned on. As a result, the output signal of Tsf 208 is output as a pixel signal. Thereafter, the signal TN is turned ON for a predetermined period. The signal TN is a signal that defines the timing for holding the pixel signal (N reading signal) corresponding to the noise charge accumulated in the FD 203 after the FD 203 is reset.

  When the signal TN is turned ON, a signal corresponding to the noise charge of the FD 203 after reset is read and output as a pixel signal. Then, the signal level of the pixel signal is held in a first holding circuit (not shown).

  Subsequently, in a period T44, Tx205 is turned on. As a result, in the first pixel, the charge held in the charge holding unit 202 is transferred to the FD 203. On the other hand, in the second pixel, the charge accumulated in the PD 201 is transferred to the FD 203.

  As described above, in the first pixel, the channel potential of the charge holding unit 202 is set higher than the channel potential of the PD 201. Further, when the charge held in the charge holding unit 202 is read out to the FD 203, the channel potential of the charge holding unit 202 is set lower than the channel potential of the FD 203 so that all the charges are read out to the FD 203.

  In the second pixel, the channel potential of the FD 201 is made lower than the channel potential of the FD 203 in order to read all the charges of the PD 201 to the FD 203.

  Thereby, in the first and second pixels, the output signal of Tsf 208 is output as a pixel signal in accordance with the charge transferred to the FD 203. The signal level of the pixel signal is held in a second holding circuit (not shown) at the timing when the signal TS is turned on.

  Here, in the first pixel, the accumulation period is a period from when the PD 201 is reset in the period T 41 to when Tx 204 is turned on in the period T 43 and the charge of the PD 201 is read out to the charge holding unit 202.

  On the other hand, in the second pixel, the period from the reset of the PD 201 in the period T41 to the ON of the Tx 205 in the period T44 until the charge of the PD 201 is read out to the FD 203 is an accumulation period.

  As described above, the signal TN is a signal for holding a pixel signal (N reading signal) corresponding to the noise charge accumulated in the FD 203 after the FD 203 is reset. On the other hand, the signal TS is a signal for holding a pixel signal (S reading signal) corresponding to the charge obtained by adding the signal charge accumulated in the PD to the noise charge. Although not shown in FIG. 2, the solid-state imaging device includes first and second holding circuits that hold the signal levels of the N reading signal and the S reading signal output by the pixel selected by Tsel 209 at a predetermined timing. Is provided.

  Then, by subtracting the signal level of the N reading signal held when the signal TN is turned on from the signal level of the S reading signal held when the signal TS is turned on, the noise component specific to the FD 203 can be removed.

  FIG. 5 is a diagram for explaining an operation concept of the solid-state imaging device shown in FIG.

  Referring to FIGS. 1, 2, and 5, all the first pixels and the second pixels are collectively reset in a period T41. Next, in a period T42, charges are accumulated in the PD 201 in all the first pixels and the second pixels.

  Subsequently, in a period T43, charges accumulated in the PD 201 in all the first pixels are collectively transferred to the charge holding unit 202. On the other hand, in the period T43, the charge accumulation state of the PD 301 is maintained in the second pixel. In other words, during the charge accumulation period in the second pixel, the charge accumulated in the PD 201 in the first pixel is transferred to the charge holding unit 202.

  In a period T44, signals are sequentially read from the first row for each row. That is, when the accumulation period in the second pixel ends, signal reading is performed. Here, in the first pixel, until the signal is read, the charge holding unit 202 holds the charge and waits for reading. On the other hand, in the second pixel, a standby for reading is performed in a state where charges are accumulated in the PD 201.

  Accordingly, even if the read amplifier 15 is driven during the read period and amplifier light emission occurs, the first pixel is in a state where the charge holding unit 202 holds the charge and waits for reading. It is possible to reduce the influence of amplifier light emission.

  Furthermore, in the solid-state imaging device shown in FIG. 1, since the first pixel having the charge holding unit 202 is arranged only in the right HOB region, it is possible to suppress an increase in circuit scale.

  FIG. 6 is a plan view schematically showing another example of the layout of the solid-state imaging device described in FIG. 2, (a) is a diagram showing the first pixel, and (b) is the second pixel. FIG.

  In the example shown in FIGS. 3A and 3B, the pixel size of the first pixel is larger than the pixel size of the second pixel. On the other hand, as shown in FIGS. 6A and 6B, the pixel size of the first pixel can be made equal to the pixel size of the second pixel.

  The first pixel formed in the light-shielded right HOB region 12 (FIG. 1) may have a smaller dynamic range than the second pixel formed in the non-light-shielding effective portion 14. Accordingly, as shown in FIG. 6A, the area of the PD 601 of the first pixel can be made smaller than the area of the PD 602 of the second pixel shown in FIG. 6B. If the charge holding units 202, Tx204, and Tres206 are arranged in the vacant space in the first pixel, the pixel size of the first pixel is made equal to the pixel size of the second pixel, Furthermore, the circuit scale can be reduced.

  Subsequently, an example of an imaging apparatus using the above-described solid-state imaging device will be described.

  FIG. 7 is a block diagram illustrating an example of an imaging apparatus in which the solid-state imaging device described in FIG. 1 is used.

  Referring to FIG. 7, the illustrated imaging device is, for example, a digital camera, and obtains image data by imaging a subject or the like. This imaging apparatus includes a CMOS solid-state imaging device 701 described with reference to FIG. An optical image is formed on the solid-state image sensor 701 through a photographing lens (not shown).

  The solid-state image sensor 701 outputs an electrical signal (analog signal: image signal) corresponding to the optical image. This analog signal is sent to an analog front end (AFE) 702. The AFE 702 performs horizontal OB clamping on the analog signal and performs analog-digital conversion (AD) processing to output image data.

  A digital front end (DFE) 703 performs digital processing such as correction of image data and rearrangement of pixel data, and outputs the image data to an image processing unit 703 (correction value calculation means and correction means). The image processing unit 704 performs various image processing such as predetermined pixel interpolation processing, color conversion processing, and pattern noise correction processing described later on the image data (output from the DFE 703), and then displays the image on the display circuit 708 as an image. To do. Further, the output of the DFE 703 is given to the control circuit 706, and the control circuit 703 records the image data in the recording circuit 709.

  A memory circuit 705 is a working memory of the image processing unit 704, and is also used as a buffer memory in continuous shooting or the like. The control circuit 706 includes, for example, a CPU and comprehensively controls the entire imaging apparatus. The operation circuit 707 is provided in the imaging apparatus and receives an instruction from an operation unit (not shown) operated by the user.

  The display circuit 708 displays an image and the like as described above, and is, for example, a TFT (Thin Film Transistor) type LCD (Liquid Crystal Display). The recording circuit 709 is a recording medium such as a memory card or a hard disk.

  Note that the timing generation circuit (TG) 710 generates various timing signals (various signals described in FIG. 4) for driving the image sensor 701 under the control of the control circuit 706.

  FIG. 8 is a block diagram showing a configuration of the analog front end (AFE) 702 shown in FIG.

  In FIG. 8, the AFE 702 (correction means) has a gain control amplifier (AMP) 81, a horizontal OB clamp circuit 82, and an analog-digital conversion circuit (AD) 83. The AMP 81 receives the image signal and the output of the horizontal OB clamp circuit 82 from the solid-state image sensor 701 and performs sensitivity adjustment.

  The AD 83 receives the output of the AMP 81, converts it into, for example, a 14-bit digital signal, and outputs it. This digital signal is applied to the horizontal OB clamp circuit 82, and the horizontal OB clamp circuit 82 corrects the gentle dark shading in the row direction of the digital signal to match the black level reference value. Further, the horizontal OB clamp circuit 82 performs offset correction so that the difference (difference) between the output of the HOB area of each row and the black level reference value decreases.

  In the correction in the horizontal OB clamp circuit 82, the correction amount is integrated as the line advances, so that it follows only a gradual change and is not affected by noise in the HOB region. Note that the processing in the horizontal OB clamp circuit 82 may be performed in the DFE 703.

  As described above, the output of the horizontal OB clamp circuit 82 is given to the AMP 81, and the AMP 81 performs gain adjustment (sensitivity adjustment) so that the pixel output in the HOB area matches the black level reference value, and outputs an analog signal (image signal). Output.

  Next, a pattern noise correction process performed by the image processing unit 705 shown in FIG. 7 will be described.

  The pattern noise correction process is a process for correcting horizontal line noise generated in the entire selected row due to power supply fluctuation during reading of the selected row. While the component that changes gently in the row direction is corrected by the horizontal OB clamp processing, the noise of the high-frequency component that occurs in the row direction is corrected in the pattern noise correction processing.

  Since the horizontal noise occurs in both the pixels of the effective portion 14 (FIG. 1) and the pixels in the OB area, the average value for each row is calculated from the pixel output in the HOB area, and the black level reference value is calculated from the average value. The amount of noise for each row is calculated by subtracting. Then, the noise amount for each row is subtracted from the pixel output of the effective unit 14 to correct the horizontal line noise.

  Here, in the solid-state imaging device illustrated in FIG. 1, the pixels in the right HOB region 12 are first pixels having the charge holding unit 202 illustrated in FIG. 3A, and each of the left HOB region 11 and the effective unit 14. Is a second pixel that does not have the charge holding portion shown in FIG. That is, the right HOB area 12, the left HOB area 11, and the effective portion 14 have different pixel structures and pixel sizes. For this reason, the influence on the pixel output caused by fluctuations in the power supply and the like is different between the right HOB area 12, the left HOB area 11, and the effective portion. Therefore, in consideration of the difference in pixel structure, the correction noise amount obtained by multiplying the noise amount obtained from the pixel output of the right HOB region 12 by the correction coefficient is used for correction.

  FIG. 9 is a block diagram for explaining pattern noise correction performed by the image processing unit 704 shown in FIG.

  In FIG. 9, in blocks 91 and 92, the average value of the pixel output for each row of the right HOB region 12 and the left HOB region 11 is calculated. In block 93, the black level reference value is subtracted from the average value of the pixel output for each row of the right HOB area 12 calculated in block 91, and further multiplied by a correction coefficient A determined by the pixel structure of the right HOB area 12.

  In block 94, the black level reference value is subtracted from the average value of the pixel output for each row in the left HOB region 11 calculated in block 92, and further multiplied by a correction coefficient B determined by the pixel structure of the left HOB region 11. Here, since the left HOB region 11 has the same pixel structure as that of the effective portion 14, the correction coefficient B = 1.

  In block 95, the average value of the values calculated in blocks 93 and 94 is calculated for each row, and this average value is used as the correction value for each row. In block 96, the correction value calculated in block 95 is subtracted for each row from the pixel output of the valid section 14, and output.

  By such pattern noise correction processing, even if the pixel structure is different from that of the effective portion 14 in a part of the horizontal OB area, it is possible to effectively correct horizontal line noise.

  As mentioned above, although this invention was demonstrated based on embodiment, this invention is not limited to these embodiment, Various forms of the range which does not deviate from the summary of this invention are also contained in this invention. .

  For example, the function of the above embodiment may be used as a control method, and this control method may be executed by the imaging apparatus. In addition, a control program having the functions of the above-described embodiments may be executed by a computer included in the imaging apparatus.

  At this time, each of the control method and the control program has at least a first step, a second step, and a third step. The control program is recorded on a computer-readable recording medium, for example.

  The present invention is also realized by executing the following processing. That is, software (program) that realizes the functions of the above-described embodiments is supplied to a system or apparatus via a network or various storage media, and a computer (or CPU, MPU, etc.) of the system or apparatus reads the program code. It is a process to be executed. In this case, the program and the storage medium storing the program constitute the present invention.

11 Left horizontal OB area 12 Right horizontal OB area 13 Vertical OB area (VOB)
14 Valid portion 15 Read amplifier 201, 601, 602 Photodiode (PD)
202 Charge holding part 203 Floating diffusion (FD)
204, 205 Transfer MOS transistor 206, 207 Reset MOS transistor 208 Source follower MOS transistor 209 Select MOS transistor

Claims (8)

An image pickup device having a pixel region in which a plurality of pixels are arranged in a two-dimensional matrix, wherein the pixel region includes a light-shielded pixel region where the pixel is shielded from light and an effective pixel region where the pixel is not shielded from light Because
A first photoelectric conversion unit that generates a charge according to light, a charge holding unit that temporarily stores the charge accumulated in the first photoelectric conversion unit, and a charge that is accumulated in the charge holding unit is transferred A first pixel having a first floating diffusion section, amplifying the charge accumulated in the first floating diffusion section and outputting the first pixel signal;
A second photoelectric conversion unit that generates a charge corresponding to light; and a second floating diffusion unit to which the charge accumulated in the second photoelectric conversion unit is transferred, the second floating diffusion unit And a second pixel that amplifies the charge accumulated in the pixel and outputs it as a second pixel signal,
The first pixel is used as the pixel in at least a part of the light-shielding pixel region, and the second pixel is used as the pixel in the effective pixel region,
An image pickup device, wherein charge is transferred from the first photoelectric conversion unit to the charge holding unit during a storage period in which charge is stored in the second photoelectric conversion unit. The light-shielding pixel region is disposed so as to surround the effective pixel region;
A read amplifier disposed outside the pixel region and amplifying the first and second pixel signals;
The image sensor according to claim 1, wherein a part of the light-shielding pixel region is a light-shielding pixel region located in the vicinity of the readout amplifier.   The image sensor according to claim 1, wherein a dynamic range of the first pixel is the same as a dynamic range of the second pixel.   The dynamic range of the first pixel is made smaller than the dynamic range of the second pixel, and the area of the first photoelectric conversion unit is made smaller than the area of the second photoelectric conversion unit. The imaging device according to claim 1 or 2. In an imaging device that captures an image of a subject and obtains image data,
The imaging device according to any one of claims 1 to 4,
Correction means for adjusting a black level of the pixel signal output from the effective pixel region to the black level reference value according to a difference between the pixel signal output from the first pixel and a black level reference value; An imaging apparatus characterized by the above. In an imaging device that captures an image of a subject and obtains image data,
The imaging device according to any one of claims 1 to 4,
Correction value calculation means for obtaining a correction value by multiplying a difference between a pixel signal output from the first pixel and a black level reference value by a correction coefficient defined by the structure of the first pixel;
An image pickup apparatus comprising: a correction unit that corrects a pixel signal output from the effective pixel region with the correction value. An image pickup device having a pixel region in which a plurality of pixels are arranged in a two-dimensional matrix, wherein the pixel region includes a light-shielded pixel region where the pixel is shielded from light and an effective pixel region where the pixel is not shielded from light Control method,
In the pixel region, a first photoelectric conversion unit that generates charges according to light, a charge holding unit that temporarily stores charges accumulated in the first photoelectric conversion unit, and a charge holding unit that stores the charges. A first pixel for amplifying the charge accumulated in the first floating diffusion unit and outputting it as a first pixel signal;
A second photoelectric conversion unit that generates a charge corresponding to light; and a second floating diffusion unit to which the charge accumulated in the second photoelectric conversion unit is transferred, the second floating diffusion unit And a second pixel that amplifies the charge accumulated in the pixel and outputs it as a second pixel signal,
The first pixel is used as the pixel in at least a part of the light-shielding pixel region, and the second pixel is used as the pixel in the effective pixel region,
A first step of accumulating charges in the first and second photoelectric conversion units;
A second step of transferring the charge from the first photoelectric conversion unit to the charge holding unit during the charge accumulation period;
When the accumulation of the electric charge is completed in the second photoelectric conversion unit, the electric charge accumulated in the second photoelectric conversion unit is transferred to the second floating diffusion unit, and the electric charge held in the electric charge holding unit And a third step of transferring to the first floating diffusion section. An image pickup device having a pixel region in which a plurality of pixels are arranged in a two-dimensional matrix, wherein the pixel region includes a light-shielded pixel region where the pixel is shielded from light and an effective pixel region where the pixel is not shielded from light A control program for performing read control of
In the pixel region, a first photoelectric conversion unit that generates charges according to light, a charge holding unit that temporarily stores charges accumulated in the first photoelectric conversion unit, and a charge holding unit that stores the charges. A first pixel for amplifying the charge accumulated in the first floating diffusion unit and outputting it as a first pixel signal;
A second photoelectric conversion unit that generates a charge corresponding to light; and a second floating diffusion unit to which the charge accumulated in the second photoelectric conversion unit is transferred, the second floating diffusion unit And a second pixel that amplifies the charge accumulated in the pixel and outputs it as a second pixel signal,
The first pixel is used as the pixel in at least a part of the light-shielding pixel region, and the second pixel is used as the pixel in the effective pixel region,
On the computer,
A first step of accumulating charges in the first and second photoelectric conversion units;
A second step of transferring the charge from the first photoelectric conversion unit to the charge holding unit during the charge accumulation period;
When the accumulation of the electric charge is completed in the second photoelectric conversion unit, the electric charge accumulated in the second photoelectric conversion unit is transferred to the second floating diffusion unit, and the electric charge held in the electric charge holding unit And a third step of transferring the program to the first floating diffusion section.

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