JP2020039176A - Imaging element - Google Patents

Abstract

To suppress a reduction in an area of a light receiving areas of a plurality of photoelectric conversion units to prevent deterioration of imaging characteristics.SOLUTION: The imaging element includes: four photoelectric conversion units arranged two by two in a first direction and a second direction intersecting the first direction; and first and second charge holding units to which charges of the photoelectric conversion units are transferred. The four photoelectric conversion units include: a first photoelectric conversion unit and a second photoelectric conversion unit sequentially arranged in the first direction; the first photoelectric conversion unit and a third photoelectric conversion unit sequentially arranged in the second direction; and the second photoelectric conversion unit and a fourth photoelectric conversion unit arranged in the second direction in order. Charges generated by the first photoelectric conversion unit and the fourth photoelectric conversion unit are transferred to the first charge holding unit. Charges generated by the second photoelectric conversion unit and the third photoelectric conversion unit are transferred to the second charge holding unit.SELECTED DRAWING: Figure 2

Description

  The present invention relates to an image sensor.

2. Description of the Related Art There is known an imaging device in which a plurality of pixels provided with a plurality of pairs of photoelectric conversion units are arranged and capable of performing focus detection by a phase difference method using outputs from the pixels (for example, Patent Document 1). Such an image sensor has a problem that the light receiving area of the photoelectric conversion unit is reduced.

JP 2012-215785 A

According to the first aspect of the present invention, the image pickup device includes: four photoelectric conversion units disposed two by two in a second direction intersecting the first direction and the first direction; and the photoelectric conversion unit A first and a second charge holding unit to which charges are transferred, wherein the four photoelectric conversion units are a first photoelectric conversion unit and a second photoelectric conversion unit which are sequentially arranged in the first direction. A first photoelectric conversion unit and a third photoelectric conversion unit sequentially arranged in the second direction, the second photoelectric conversion unit and a fourth photoelectric conversion unit sequentially arranged in the second direction, The charge generated by the first photoelectric conversion unit and the fourth photoelectric conversion unit is transferred to the first charge holding unit, and the charge generated by the second photoelectric conversion unit and the third photoelectric conversion unit is The data is transferred to the second charge holding unit.
According to a second aspect of the present invention, the image pickup device comprises: four photoelectric conversion units disposed two by two in a second direction intersecting the first direction and the first direction; First and second signal lines for outputting a signal based on the electric charges of the first and second photoelectric conversion units, wherein the four photoelectric conversion units are a first photoelectric conversion unit and a second photoelectric conversion unit that are sequentially arranged in the first direction; The first photoelectric conversion unit and the third photoelectric conversion unit sequentially arranged in the second direction, the second photoelectric conversion unit and the fourth photoelectric conversion unit sequentially arranged in the second direction, The signal based on the charge generated by the first photoelectric conversion unit and the fourth photoelectric conversion unit is output to the first signal line, and the charge generated by the second photoelectric conversion unit and the third photoelectric conversion unit Is output to the second signal line.
According to a third aspect of the present invention, a focus detection device comprises: an image sensor according to the first or second aspect;
A control unit that controls the transfer of charges from the four photoelectric conversion units; and the photoelectric conversion units, which are sequentially arranged in the first direction, among the four photoelectric conversion units, or the second direction. And a focus detection unit that performs phase-difference focus detection based on signals generated by the photoelectric conversion units, which are arranged in this order.
According to a fourth aspect of the present invention, there is provided an imaging apparatus comprising: a focus detection device according to a third aspect; a charge of the first and second photoelectric conversion units; and a charge of the third and fourth photoelectric conversion units. And an image generation unit that generates image data based on the image data.

FIG. 1 is a diagram illustrating a configuration example of a digital camera according to an embodiment of the present invention. The figure which shows the schematic structure of an imaging element FIG. 2 is a diagram schematically showing a first region and a second region on an image sensor. FIG. 2 is a diagram schematically illustrating a circuit configuration of an image sensor according to the first embodiment. FIG. 4 is a diagram illustrating drive timing for reading an output signal from a pixel according to the first embodiment. FIG. 2 is a diagram schematically illustrating a circuit configuration of an image sensor according to the first embodiment. FIG. 4 is a diagram illustrating drive timing for reading an output signal from a pixel according to the first embodiment. The figure which shows the schematic structure of the imaging element in a comparative example FIG. 2 is a diagram schematically illustrating a circuit configuration of an image sensor in a comparative example. The figure which shows the schematic structure of the imaging element in a comparative example FIG. 2 is a diagram schematically illustrating a circuit configuration of an image sensor in a comparative example. FIG. 4 is a diagram schematically illustrating a circuit configuration of an image sensor according to a second embodiment. FIG. 13 is a diagram illustrating drive timing for reading output signals from pixels according to the second embodiment. FIG. 13 is a diagram illustrating drive timing for reading output signals from pixels according to the second embodiment.

-1st Embodiment-
Hereinafter, an embodiment will be described with reference to the drawings. FIG. 1 is a block diagram illustrating a configuration of an interchangeable lens digital camera 1 including an image sensor according to the present embodiment. 1 includes an interchangeable lens 110 and a camera body 100, and the interchangeable lens 110 is mounted on the camera body 100 via a lens mounting portion 105.

The interchangeable lens 110 includes a lens control device 111, a zoom lens 112, a focus lens 113, an anti-vibration lens 114, an aperture 115, a lens operation unit 116, and the like. The lens control device 111 includes a CPU and peripheral components such as a memory, and controls the driving of the focus lens 113 and the aperture 115, detects the positions of the zoom lens 112 and the focus lens 113,
Transmission of lens information to the camera body 100 and reception of camera information from the camera body 100 are performed.

The camera body 100 includes an imaging device 101, a body control device 102, a body operation unit 103
, And a display unit 104. The imaging element 101 is arranged on a planned imaging plane (planned focal plane) of the interchangeable lens 110, and photoelectrically converts a subject image formed by the interchangeable lens 110. The body operation unit 103 includes a shutter button, a focus detection area setting member, and the like. The display unit 104 is a liquid crystal monitor (rear monitor) mounted on the back of the camera body 100
It is.

Body control device 102 includes a CPU and peripheral components such as a memory. Body control device 1
An arithmetic device 02 controls each component of the digital camera 1 and executes various data processing based on a control program. The body control device 102 includes a drive control unit 102a
And a focus detection unit 102b and an image processing unit 102c as functions. The drive control unit 102a controls the drive control of the image sensor 101 to read out an image signal and a focus detection signal from the image sensor 101. The focus detection unit 102b performs focus detection calculation based on a focus detection signal from the image sensor 101 and adjusts the focus of the interchangeable lens 110. The image processing unit 102c processes and records an image signal from the image sensor 101. The body control device 102 communicates with the lens control device 111 via an electrical contact 106 provided on the lens mounting unit 105, and receives lens information and transmits camera information (defocus amount, aperture value, etc.).

An image of a subject is formed on the light receiving surface of the image sensor 101 by the light beam that has passed through the interchangeable lens 110. This subject image is photoelectrically converted by the image sensor 101, and an image signal and a focus detection signal are sent to the body control device 102.

The focus detection unit 102b of the body control device 102 performs a focus detection calculation by a known image plane phase difference method based on a focus detection signal from the image pickup device 101, so that the interchangeable lens 110
Is detected (the defocus amount). The body control device 102 sends this defocus amount to the lens control device 111. The lens controller 111 calculates a drive amount of the focus lens 113 based on the received defocus amount, and drives the focus lens 113 by a motor or the like (not shown) based on the drive amount to move the focus lens 113 to a focus position. In other words, the imaging device 101, the drive control unit 102a, and the focus detection unit 102b constitute the focus detection device 2 in the present embodiment.

The image processing unit 102c of the body control device 102 processes the image signal from the image sensor 101 to generate captured image data, and stores the data in a memory card (not shown). Image processing unit 10
2c causes the display unit 104 to display a through image (live view image) based on a through image (live view image) signal from the image sensor 101.

(Configuration of imaging device)
FIG. 2 is a diagram illustrating a schematic configuration of the image sensor 101. Note that in FIG.
In order to make the connection between 00 and the vertical signal line 300 easy to understand, transistors and the like used for reading are omitted. In the image sensor 101, a plurality of pixels 200 are provided two-dimensionally in a horizontal direction (row direction) and a vertical direction (column direction). Hereinafter, the plurality of pixels 200 arranged in the horizontal direction are also referred to as a pixel row, and the plurality of pixels 200 arranged in the vertical direction are also referred to as a pixel column.

Each pixel 200 has four photoelectric conversion units (photodiodes) PD_1, PD_2, PD_3, and PD_4 provided below one microlens (not shown). Each photoelectric conversion unit PD
_1, PD_2, PD_3, and PD_4 respectively receive the four light beams that have passed through different regions of the exit pupil of the interchangeable lens 110. In the following description, the photoelectric conversion units PD_1 to PD_
4 is generally referred to as a photoelectric conversion unit PD. The photoelectric conversion unit PD is a charge storage type photoelectric conversion unit. In the case of a 4PD configuration having four photoelectric conversion units PD per pixel, if two photoelectric conversion units PD are arranged in a horizontal direction (referred to as horizontal division), two photoelectric conversion units PD are arranged in a vertical direction (vertical division and Call). In the example illustrated in FIG. 2, the photoelectric conversion units PD_1 and PD_3 are arranged in the horizontal direction, and the photoelectric conversion units PD_2 and PD_4 are arranged in the horizontal direction. Photoelectric conversion unit PD_1
And PD_4 are arranged in the vertical direction, and the photoelectric conversion units PD_2 and PD_3 are arranged in the vertical direction.
That is, the four photoelectric conversion units PD are arranged in two rows and two columns.

In addition, a color filter (R: red filter,
G: green filter, B: blue filter). That is, as the pixel 200, an R pixel having a spectral sensitivity of a red component (that is, a red filter is disposed), a G pixel having a spectral sensitivity of a green component (that is, a green filter is disposed), and a spectral sensitivity of a blue component are B pixels (ie, a blue filter is disposed). Pixel 200
Has both a photographing pixel and a focus detection pixel, and a pixel 200 is arranged on the entire surface of the image sensor 101. Therefore, it is possible to perform focus detection at an arbitrary position on the shooting screen. At the time of shooting, the photoelectric conversion units PD_1, PD_2, PD_3 and P
It is possible to generate captured image data by adding the output signals from D_4.

The image sensor 101 includes a vertical signal line 300 for reading an output signal from the photoelectric conversion unit PD.
Having. While the image sensor 101, each pixel column every two vertical signal lines 300 ₍₃₀₀ 1-3
_002n ) is provided. For example, the pixel 200 in the first column has a vertical signal line 300 ₁
And the vertical signal line 300 ₂ is provided. The vertical signal lines 300 _1, and the left of the photoelectric conversion unit PD_4 and right of the photoelectric conversion unit PD_3 of the pixels of the first column 200 is connected. Vertical signal line 300
₂ , the left photoelectric conversion unit PD_1 and the right photoelectric conversion unit PD_2 of the pixel 200 in the first column are connected. That is, the vertical signal lines 300 _1, is placed diagonally photoelectric conversion unit PD
_3 and PD_4 and are connected to the vertical signal line 300 ₂ above and the photoelectric conversion unit PD_1 disposed in different diagonal directions and PD_2 are connected.

The two photoelectric conversion units PD arranged in the row direction in one pixel 200 are read out to different vertical signal lines 300, respectively. For example, in the pixel 200 in the first column, the left photoelectric conversion unit P
D_1 is read out to the vertical signal line 300 _2, the right of the photoelectric conversion unit PD_3 vertical signal line 300
Read to ₁ . The photoelectric conversion unit PD_4 the left is read out to the vertical signal line 300 _1, the right of the photoelectric conversion unit PD_2 is read to the vertical signal line 300 _2. In the above configuration, the pixel 200
Are arranged in n columns, whereas 2n vertical signal lines 300 are required, but the influence on the entire area is small.

The drive control unit 102a controls the pixel 200 having the above configuration to read output signals from the photoelectric conversion units PD arranged in the vertical direction at the same timing (first control), and to control the pixels 200 arranged in the horizontal direction. Control (second control) of reading output signals from the conversion unit PD at the same timing is performed.
FIG. 3 shows a plurality of pixels 200 as a pixel group controlled by the first control on the image sensor 101.
(A first region) R1 in which a plurality of pixels 200 are arranged as a pixel group controlled by the second control. The first region R1 and the second region R2 include a plurality of pixel rows in the vertical direction, and the first region R1 and the second region R2 are provided alternately along the vertical direction. Note that the arrangement of the first region R1 and the second region R2 shown in FIG. 3 is an example, and is not limited to this arrangement example. Hereinafter, the pixels 20 arranged in the first region R1
0 and the pixel 200 arranged in the second region R2 will be separately described. In the following description, terms such as the same timing and synchronization are used, but are not limited to the same timing and the same timing in a strict sense, and include a time width that does not reduce the accuracy of the focus detection calculation.

-Pixels arranged in first region R1-
FIG. 4 is a diagram showing details of FIG. 2 and shows connection at the transistor level. FIG. 4 shows a circuit configuration of one pixel 200 included in the first region R1 among the plurality of pixels 200 shown in FIG. Each pixel 200 of the image sensor 101 has a reading unit 400 for reading an output signal from the photoelectric conversion unit PD. Each pixel 200 is provided with _two read-out units 400 ₁ and 400 _2, and two photoelectric conversion units P each arranged diagonally.
D is provided in common. For example, in a photoelectric conversion unit PD_3 and PD_4 are read unit 400 ₁ are commonly provided, read the photoelectric conversion unit PD_1 and PD_2 is 400
₂ are provided in common. That is, the reading unit 400 ₁ reads the output signal from the photoelectric conversion unit Pd_3, the output signal from the photoelectric conversion unit PD_4. Reading unit 400 ₂ reads the output signal from the photoelectric conversion unit PD_1, the output signal from the photoelectric conversion unit PD_2. The output signal read from each reading unit 400 is output via the corresponding vertical signal line 300. For example, the output signal read from the read unit 400 _1, the vertical signal line 3
00 is ₁ through an output, the output signal read from the read unit 400 ₂ is outputted through the vertical signal line 300 _2.

Each read unit 400 includes a reset transistor RST (RST ₁ , RST ₂ ), an amplification transistor SF (SF ₁ , SF ₂ ), a selection transistor SEL (SEL ₁ , SEL ₂ ),
Floating diffusion FD (FD ₁ , FD ₂ ), transfer transistor TX 1 (T
X1 ₁ , TX1 ₂ ) and TX2 (TX2 ₁ , TX2 ₂ ). The floating diffusion FD accumulates signal charges obtained by photoelectric conversion in the photoelectric conversion unit PD (
It operates as a charge accumulating portion or a charge holding portion for holding. The amplification transistor SF operates as an amplification unit that amplifies a signal corresponding to the potential of the floating diffusion FD.
Each of the transfer transistors TX1 and TX2 operates as a transfer unit that transfers charges from the photoelectric conversion unit to the floating diffusion FD. The reset transistor RST operates as a reset unit that resets the potential of the floating diffusion FD and the charge of the photoelectric conversion unit. The selection transistor SEL operates as a selection unit for selecting the pixel 200. These components are connected as shown in FIG. In FIG. 4, VDD is a power supply voltage.

The photoelectric conversion units PD arranged in the row direction of each pixel 200 are provided with separate readout units 400, respectively.
Are connected to the transfer transistors TX1 and TX2. For example, in the pixel 200, the photoelectric conversion unit PD_1 on the left is connected to the transfer transistor TX1 ₂ read unit 400 _2, the right side of the photoelectric conversion unit PD_2 is connected to the transfer transistor TX2 ₂ read unit 400 _2. Right of the photoelectric conversion unit PD_3 is connected to the transfer transistor TX1 ₁ read unit 400 _1, the photoelectric conversion unit PD_4 the left is connected to the transfer transistor TX2 ₁ read unit 400 _1.

The photoelectric conversion unit PD_1 pixel 200, the transfer transistor connected to PD_4 _TX1 2, T
X2 ₁ gate is connected to the control line 210 to control pulse Vtx_1 by the local control line 211 is supplied. On the other hand, the photoelectric conversion unit PD_3 pixel 200, the transfer transistor _TX1 1 which are respectively connected to PD_2, TX2 ₂ gate is connected to the control line 220 to control pulse Vtx_2 by the local control line 221 is supplied. That is, the pixel 200
Of the photoelectric conversion unit PD on the left of the transfer transistor TX1 by the control pulse Vtx_1.
, TX2 is controlled, and for the right photoelectric conversion unit PD, the control of the transfer transistors TX1, TX2 is performed by the control pulse Vtx_2.

(Reading of output signal)
Referring to the timing chart shown in FIG. 5, the pixel 2 of the image sensor 101 of the present embodiment is described.
Control for reading an output signal from 00 will be described. In FIG. 5, Vsel indicates a control pulse of the selection transistor SEL. Vrst indicates a control pulse of the reset transistor RST. Vtx_1 shows transfer transistor _TX1 2, TX2 ₁ control pulse corresponding to the left side of the photoelectric conversion unit PD_1, PD_4 pixel 200. Vtx_2 is the pixel 20
0 on the right of the photoelectric conversion unit Pd_3, the transfer transistor _TX1 1 corresponding to PD_2, TX2 ₂
3 shows the control pulse of FIG. These points are the same in FIGS. 7, 13, and 14 described later.

As illustrated in FIG. 5, the drive control unit 102 a controls a drive timing for reading an output signal from the pixel 200 by outputting various control pulses to the read unit 400.
The drive control unit 102a selects a pixel row from which an output signal is read. The drive control unit 102a switches Vsel from a low level to a high level, and turns on the selection transistor SEL. Thereby, the connection from the floating diffusion FD to the vertical signal line 300 is connected. FIG. 5 shows an example in which selection is performed line by line.

The drive control unit 102a switches Vrst from the Low level to the High level, turns on the reset transistor RST, and resets the potential of the floating diffusion FD. This is the first reset of the floating diffusion FD. After that, the drive control unit 102a switches Vrst to Low level to turn off the reset transistor RST. After the reset transistor RST is turned off, the potential level of the floating diffusion FD is settled for a predetermined settling time. This settled level is a dark level by the first reset, and is a dark signal corresponding to the photoelectric conversion units PD_1 and PD_4 on the left side of the pixel 200. Here, each vertical signal lines ₃₀₀ 1 to 300 _2n, 1 st left photoelectric conversion unit PD_1 pixels 200 in each column by resetting, the dark signal "Dark_4 ₁ for _{PD_4, 1 2, 4 3,} 1 ₄ , 4, ₅ , ₁₆ , ..., 4 _(2n-1)
, _1n ”are output simultaneously.

After settling of the dark level, the drive control unit 102a turns on the transfer transistor _TX1 2, TX2 ₁ connected to the photoelectric conversion unit PD_1 and PD_4 the left pixel 200 switches the Vtx_1 to High level. In the High level period of Vtx_1, the pixel 2
00 is stored in the floating diffusion FD
Is transferred to _2, the signal charge accumulated in the photoelectric conversion unit PD_4 is transferred to the floating diffusion FD _1. Drive control unit 102a, the photoelectric conversion unit PD_1 pixel 200 switches the Vtx_1 to Low level, the transfer transistor connected to PD_4 _TX1 2, T
To turn off the X2 _1.

After the transfer transistors _TX1 2, TX2 ₁ is turned off, the floating diffusion _FD 1, FD ₂ potential level is settled between a predetermined settling time. This settled potential level is a signal level obtained by reading at Vtx_1, and the photoelectric conversion unit PD_1,
The signal signals respectively correspond to PD_4. Here, each of the vertical signal lines 300 ₁ to 300 30
0 _2n , the photoelectric conversion unit PD_ on the left side in the pixel 200 of each column by charge transfer at Vtx_1.
1, the signal signal "Sig_4 ₁ for _{PD_4, 1 2, 4 3,} 1 4, 4 5, 1 6, ···,
4 _(2n-1) , 1 _2n "are simultaneously output.

The difference between the dark signal and the signal signal output from each vertical signal line 300 in this manner becomes the readout signal amount of each of the photoelectric conversion units PD_1 and PD_4 in the pixel 200, that is, the output signal. Therefore, in the plurality of pixels 200 arranged in the same pixel row, the output signals of the photoelectric conversion units PD_1 and PD_4 arranged in the vertical direction have temporal synchronization.
Note that the correlated double sampling (CD) for calculating the difference between the dark signal and the signal signal is performed.
S) The operation may be performed by a subsequent circuit in the sensor chip of the image sensor 101 or may be performed by a subsequent circuit outside the sensor chip.

After the signal level is settled, the drive control unit 102a changes Vrst from the Low level to the H level.
By switching to the high level, the reset transistor RST is turned on to reset the potential of the floating diffusion FD. This is floating diffusion FD
Is the second reset. After that, the drive control unit 102a switches Vrst to Low level to turn off the reset transistor RST. After the reset transistor RST is turned off, the potential level of the floating diffusion FD is settled for a predetermined settling time. This settled level is a dark level due to the second reset, and is a dark signal corresponding to the photoelectric conversion units PD_2 and PD_3 on the right side of the pixel 200. Here, each vertical signal line 3
00 ₁ The to 300 _2n, 2 nd photoelectric conversion portion of the right in the pixel 200 in each column by a reset PD_2, dark signal "Dark_3 ₁ for _{PD_3, 2 2, 3 3,} 2 4, 3 5, 2 6 ,
.., 3 _(2n-1) , 2 _2n "are simultaneously output.

After settling of the dark level, the drive control unit 102a, the right side of the photoelectric conversion unit PD_3 pixel 200 switches the Vtx_2 the High level to turn on the connected transfer transistor _TX1 1, TX2 ₂ to PD_2. In the High level period of Vtx_2, the pixel 200
The signal charges accumulated in the photoelectric conversion unit PD_3 of is transferred to the floating diffusion FD _1, signal charges accumulated in the photoelectric conversion unit PD_2 are transferred to the floating diffusion FD _2. Drive control unit 102a, the photoelectric conversion unit PD_3 pixel 200 switches the Vtx_2 to Low level, the transfer transistor _TX1 1 connected to PD_2, TX2
Turn ₂ off.

After the transfer transistors _TX1 1, TX2 ₂ is turned off, the potential level of the floating diffusion FD between predetermined settling time is settled. This settled potential level is Vtx_2
And the signal level corresponding to the photoelectric conversion units PD_3 and PD_2 of the pixel 200. Each vertical signal lines ₃₀₀ 1 to 300 _2n, the photoelectric conversion portion of the right in the pixel 200 in each column by charge transfer in Vtx_2 PD_3, signaling signal "Sig_3 ₁ for _{PD_2, 2 2, 3 3,} 2 4, 3 ₅ , 2 ₆ ,..., 3 _(2n−1) , 2 _2n ”are output.

The difference between the dark signal and the signal signal output from each vertical signal line 300 in this manner becomes the readout signal amount of each of the photoelectric conversion units PD_2 and PD_3 in the pixel 200, that is, the output signal. Therefore, in the plurality of pixels 200 arranged in the same pixel row, the output signals of the photoelectric conversion units PD_2 and PD_3 arranged in the vertical direction have temporal synchronization.
Note that the correlated double sampling (CD) for calculating the difference between the dark signal and the signal signal is performed.
S) The operation may be performed by a subsequent circuit in the sensor chip of the image sensor 101 or may be performed by a subsequent circuit outside the sensor chip.

As described above, in the pixel 200, the drive control unit 102a causes the photoelectric conversion units PD_1 and PD_4 arranged in the vertical direction to output output signals at the same timing. The drive control unit 102a causes the photoelectric conversion units PD_2 and PD_3 arranged in the vertical direction to output output signals at the same timing. That is, the drive control unit 102a, identical to the transfer transistor TX1 ₂ and TX2 ₁ photoelectric conversion unit at the same timing with respect to the PD_1, to allow charge transfer from PD_4, transfer transistor TX1 ₁ and TX2 ₂ and At this timing, charge transfer from the photoelectric conversion units PD_3 and PD_2 is permitted. Therefore, the drive control unit 10
2a, relative to the transfer transistor TX1 ₂ connected to each of the photoelectric conversion unit PD_1 and PD_2 arranged in a diagonal direction of the pixel 200 TX2 ₂ and are alternatively permit charge transfer. The drive control unit 102a includes a photoelectric conversion unit PD_3 arranged in a diagonal direction of the pixel 200.
Against the PD_4 a transfer transistor TX1 ₁ connected to each of the TX2 ₁ and,
Alternatively, charge transfer is allowed.
Accordingly, charge transfer can be performed without providing a floating diffusion for each of the photoelectric conversion units PD_1 to PD_4, so that the number of components can be reduced and the area of the light receiving surfaces of the photoelectric conversion units PD_1 to PD_4 can be increased. it can.

Note that, in the above description, the drive control unit 102a determines that the pixels 200 in the first region R1
After the output signals are output from the photoelectric conversion units PD_1 and PD_4, the photoelectric conversion units PD_2 and PD_3 are output.
Although the drive timing is controlled so that an output signal is output from the controller, the present invention is not limited to this example.
The drive control unit 102a performs the photoelectric conversion units PD_2 and PD_ for the pixels 200 in the first region R1.
After the output signal is output from the control signal 3, the drive timing may be controlled so that the output signal is output from the photoelectric conversion units PD_1 and PD_4.

The drive control unit 102a performs the above control for each pixel row included in the first region R1 of the image sensor 101, and reads out an output signal.
(Focus detection)
When performing focus adjustment according to the half-press operation of the shutter button by the user, the focus detection unit 102b uses the output signal read as described above as a focus detection signal,
A focus detection calculation is performed by a known image plane phase difference method. In this case, the focus detection unit 102b generates a signal sequence using a plurality of output signals having temporal synchronization. For example, the focus detection unit 102b generates a first signal sequence {an} using the output signal from the photoelectric conversion unit PD_1 in each row, and generates the second signal sequence {an} using the output signal from the photoelectric conversion unit PD_4 in each row. bn}. The focus detection unit 102b detects a focus adjustment state of the interchangeable lens 110, that is, a defocus amount, by detecting a relative image shift amount between the generated first signal sequence {an} and the second signal sequence {bn}. I do.

The focus detection unit 102b generates the first signal sequence {cn} using the output signal from the photoelectric conversion unit PD_3 in each row, and generates the second signal sequence {dn} using the output signal from the photoelectric conversion unit PD_2 in each row.
｝ May be generated. In particular, the luminous flux from the subject is more susceptible to vignetting and the like in the peripheral portion of the image sensor 101 than in the central portion of the image sensor 101. The focus detection unit 102b outputs the output signals from the pair of photoelectric conversion units PD_1 and PD_4 or the photoelectric conversion units PD_2 and PD_3, which are less affected by vignetting, among the output signals from the pixels 200 arranged around the imaging element 101. May be selected and used as the focus detection signal. For the pixel 200 disposed in the center of the image sensor 101, the focus detection unit 102b uses an output signal from one of the photoelectric conversion units PD_1 and PD_4 or one of the photoelectric conversion units PD_2 and PD_3 as a focus detection signal. Can be used.

As described above, a color filter is arranged at each pixel position of the image sensor 101 according to the Bayer arrangement rule. Therefore, the focus detection unit 102b outputs a pair of signal trains ｛an
When generating {}, {bn} or a pair of signal strings {cn}, {dn}, an output signal from the pixel 200 in which the same color filter is arranged is used. For example, when the focus detection calculation is performed using the output signals from the pixels 200 arranged in the first column as illustrated in FIG. 2, the focus detection unit 102b includes, as an example, a G color filter. Output signals from the pixels 200 in the first row, the third row,...

-Pixels arranged in second region R2-
FIG. 6 is a circuit diagram showing connection at the transistor level of each pixel 200 arranged in the second region R2, and is a diagram showing FIG. 2 in detail. FIG. 6 also shows a circuit configuration of one pixel 200 included in the second region R2 among the plurality of pixels 200 shown in FIG.
The photoelectric conversion unit PD_1 pixel 200, the transfer transistor connected to Pd_3 _TX1 2, T
X1 ₁ of gate control pulses Vt, respectively, by local control lines 251 and 252
x_1 is connected to the control line 210 to be supplied. The photoelectric conversion units PD_4 and PD_ of the pixel 200
Connected transfer transistor 2 _TX2 1, TX2 ₂ gates are respectively connected to the control line 220 to control pulse Vtx_2 by local control lines 253 and 254 are supplied. That is, the transfer transistors TX1 and TX2 are controlled by the control pulse Vtx_1 for the upper photoelectric conversion unit PD of the pixel 200, and the transfer transistors TX1 and TX2 are controlled by the control pulse Vtx_2 for the lower photoelectric conversion unit PD. Done. The other configuration, that is, the signal circuit for reading out the charges accumulated in the photoelectric conversion unit PD to the vertical signal line 300 is the same as the pixel 200 arranged in the first region R1.

(Reading of output signal)
Referring to the timing chart shown in FIG. 7, the pixel 200 arranged in the second region R2
The control at the time of reading the output signal from is described. In the following description, the first
The difference from the drive timing at the time of reading the output signal from the pixel 200 arranged in the region R1 is mainly described.
In FIG. 7, Vtx_1 shows a control pulse of the transfer transistor _TX1 2, TX1 ₁ corresponding to the upper side of the photoelectric conversion unit PD_1, Pd_3 pixel 200. Vtx_2 is the pixel 20
The photoelectric conversion unit PD_4 the lower 0, the transfer transistor corresponding to PD_2 _TX2 1, TX2 ₂
3 shows the control pulse of FIG.

As illustrated in FIG. 7, the drive control unit 102a selects a pixel row from which an output signal is read by turning on the selection transistor SEL in the same manner as in the case of the pixel 200 in the first region R1. FIG. 7 also shows an example in which selection is performed line by line. The drive control unit 102a resets the potential of the first floating diffusion FD in the same manner as in the case of the pixel 200 in the first region R1. After a predetermined settling time has elapsed, the dark signals “Dark — 31, 1” for the upper photoelectric conversion units PD — ₁ and PD — ₃ in the pixels 200 in each column by the first reset are applied to the vertical signal lines 300 _{1 to} 300 _{2 n. 2, 3 3,} 1 4, _{3 5
, 1 6, ···, 3 (} 2n-1), 1 2n "is output at the same time.

The drive control unit 102a switches Vtx_1 to a high level to switch the transfer transistor T
To turn on the X1 _2, TX1 _1. In the High level period of the Vtx_1, the signal charges accumulated in the photoelectric conversion unit PD_1 pixels 200 are transferred to the floating diffusion FD _2, the signal charge accumulated in the photoelectric conversion unit PD_3 floating diffusion F
It is transferred to the D _1. Drive control unit 102a to turn off the transfer transistor _TX1 2, TX1 ₁ switches the Vtx_1 to Low level. Thereafter, the potential levels of the floating diffusions FD ₁ and FD ₂ are settled in a predetermined settling time, and become the signal level by reading with Vtx_1. Each vertical signal lines ₃₀₀ 1 to 300 _2n, the upper photoelectric conversion section PD_1 in the pixel 200 in each column by charge transfer in Vtx_1, signaling signal "Sig_3 ₁ corresponding to the signal level for PD_3, ₁ 2, 3 _{3, 1 4,} 3 _5, 1 6,..., _{3 (2
n-1)} , _12n "are simultaneously output.

The difference between the dark signal and the signal signal output from each vertical signal line 300 as described above becomes the output signal of each of the photoelectric conversion units PD_1 and PD_3 in the pixel 200. Therefore, in the plurality of pixels 200 arranged in the same pixel row, the photoelectric conversion units PD arranged in the horizontal direction
_1 and PD_3 have temporal synchronism.
Note that the correlated double sampling (CD) for calculating the difference between the dark signal and the signal signal is performed.
S) The operation may be performed by a subsequent circuit in the sensor chip of the image sensor 101 or may be performed by a subsequent circuit outside the sensor chip.

After the signal level is settled, the drive control unit 102a resets the potential of the floating diffusion FD for the second time in the same manner as in the case of the pixel 200 in the first region R1. After the predetermined settling time has elapsed, the dark signal “D” for the lower photoelectric conversion units PD_2 and PD_4 in the pixels 200 in each column by the second reset is applied to each of the vertical signal lines 300 _{1 to} 300 _{2n.
ark_4 1, 2 2, 4 3} , 2 4, 4 5, 2 6, ···, 4 (2n-1), 2 2n "is output at the same time.

After settling of the dark level, the drive control unit 102a turns on the transfer transistors _TX2 1, TX2 ₂ switches the Vtx_2 to High level. In the High level period of the Vtx_2, the signal charges accumulated in the photoelectric conversion unit PD_4 pixels 200 are transferred to the floating diffusion FD _1, signal charges accumulated in the photoelectric conversion unit PD_2 are transferred to the floating diffusion FD _2. The drive control unit 102a sets Vtx_2 to L
turning off the transfer transistor _TX2 1, TX2 ₂ switch to ow level. After that, the potential level of the floating diffusion FD is settled in a predetermined settling time, and becomes a signal level by reading Vtx_2. Vtx is applied to each of the vertical signal lines 300 _{1 to} 300 _2n.
The photoelectric conversion unit PD_2 the lower the pixel 200 in each column by charge transfer in _2, signaling signal "Sig_4 ₁ for _{PD_4, 2 2, 4 3,} 2 4, 4 5, 2 6, ···, 4 _(2n-1) ,
2 _2n "is output.

The difference between the dark signal and the signal signal output from each vertical signal line 300 is
Are the output signals of the respective photoelectric conversion units PD_2 and PD_4. Therefore, in the plurality of pixels 200 arranged in the same pixel row, the output signals of the photoelectric conversion units PD_2 and PD_4 arranged in the horizontal direction have temporal synchronization.
Note that the correlated double sampling (CD) for calculating the difference between the dark signal and the signal signal is performed.
S) The operation may be performed by a subsequent circuit in the sensor chip of the image sensor 101 or may be performed by a subsequent circuit outside the sensor chip.

Note that the drive control unit 102a sets the photoelectric conversion unit PD for the pixel 200 in the second region R2.
_1 and PD_3, the drive timing is controlled such that the output signals are output from the photoelectric conversion units PD_2 and PD_4. However, the present invention is not limited to this example. Drive control unit 10
The drive timing may be controlled so that the pixel 2a outputs the output signal from the photoelectric conversion units PD_2 and PD_4 and then outputs the output signal from the photoelectric conversion units PD_1 and PD_3 for the pixels 200 in the second region R2.

(Focus detection)
The focus detection unit 102b performs a focus detection calculation by a known image plane phase difference method using the output signal read as described above as a focus detection signal. In this case, the focus detection unit 102
b generates a signal sequence using a plurality of output signals having temporal synchronism. For example, the focus detection unit 102b uses the output signal from the photoelectric conversion unit PD_1 in each column to generate a first signal sequence #a
n}, and a second signal sequence {bn} is generated using output signals from the photoelectric conversion unit PD_3 in each column. The focus detection unit 102b generates the first signal sequence {an} and the second signal sequence {bn
By detecting the relative image shift amount with respect to｝, the focus adjustment state of the interchangeable lens 110, that is, the defocus amount is detected. Note that the focus detection unit 102b is configured to control the photoelectric conversion units PD_
4 may be used to generate the first signal sequence {cn}, and the output signal from the photoelectric conversion unit PD_2 of each column may be used to generate the second signal sequence {dn}.

Note that the focus detection unit 102b outputs a signal from a pair of the photoelectric conversion units PD_1 and PD_3 or the photoelectric conversion units PD_2 and PD_4, which are less affected by vignetting, in the output signals from the pixels 200 arranged around the imaging element 101. An output signal may be selected and used as a focus detection signal. Also, the focus detection unit 102b outputs a pair of signal trains {an}, {bn} or a pair of signal trains {cn}.
, {Dn}, the output from the pixel 200 in which the same color filter is arranged is used. For example, when the focus detection calculation is performed using the output signal from the pixel 200 arranged in the first row as illustrated in FIG. 2, the focus detection unit 102b includes, as an example, a G color filter. The output signals from the pixels 200 in the first, third,... Columns are used.

As described above, for the output signals from the plurality of pixels 200 provided in the first region R1, the focus detection unit 102b generates a pair of signal trains along the vertical direction, and shifts the image between the signal trains. The amount of defocus is calculated by detecting the amount. For output signals from the plurality of pixels 200 provided in the second region R2, the focus detection unit 102b generates a pair of signal trains along the horizontal direction and detects an image shift amount between the signal trains. To calculate the defocus amount. Therefore, the imaging device 101 constituted by the pixels 200 having the same circuit configuration
In, detection of a vertical image shift of a subject image and detection of a horizontal image shift can be performed using output signals of the same frame.

−Image generation for shooting−
When performing a shooting operation in response to a full-press operation of the shutter button by the user, the image processing unit 102c uses the output signal read as described above as an image signal. In this case, the image processing unit 102c calculates the photoelectric conversion units PD_1 and PD_
2, output signals output from PD_3 and PD_4 are added to generate an image signal. The image processing unit 102c performs various image processing on the image signal to generate image data for photographing.

(Comparative example)
8 and 9 show the configuration of the pixel 500 in the comparative example, and FIGS. 10 and 11 show the pixel 5 in the comparative example.
No. 01 shows the configuration. FIGS. 8 and 10 are diagrams illustrating a schematic configuration of the pixels 500 and 501 in the comparative example. 8 and 10, the pixels 500 and 501 and the vertical signal line 600
In order to make the connection with (600 ₁ , 600 ₂ ) easy to understand, transistors and the like used for reading are omitted. 8 and 10 show some of the pixels 500 and 501 in the first column among the plurality of pixel columns. 9 and 11 are diagrams showing details of FIGS. 8 and 10, respectively, showing connections at the transistor level. Each of the pixels 500 and 501 has four photoelectric conversion units P
D ′ (PD′_1, PD′_2, PD′_3, PD′_4) are arranged in two rows and two columns.

In the pixel 500, the photoelectric conversion unit PD'_1 arranged vertically, the output signal from the PD'_4 is read out to the vertical signal lines 600 ₁ pixel 500, arranged in the vertical direction has been the photoelectric conversion unit PD
'_2, the output signal from the PD'_3 is read to the vertical signal line 600 _2. That is, from the photoelectric conversion units PD′_1 and PD′_4, the reset transistors RST provided in common to both are provided.
An output signal is read out via the ' ₁ , the amplification transistor SF' ₁ , the selection transistor SEL ' ₁ , and the floating diffusion FD' ₁ . Photoelectric conversion unit PD'_2, PD'_
From 3, an output signal is read through a reset transistor RST ′ ₂ , an amplification transistor SF ′ ₂ , a selection transistor SEL ′ ₂ , and a floating diffusion FD ′ ₂ which are provided in common to both. Therefore, in the pixel 500, the photoelectric conversion unit PD'_
1, the output signals from PD′_3 have temporal synchronization, and the photoelectric conversion units PD′_2, PD′_
The output signals from 4 have temporal synchrony.

In the pixel 501, the photoelectric conversion unit PD'_1 arranged horizontally, the output signal from the PD'_3 is read out to the vertical signal lines 600 ₁ pixel 501, the photoelectric conversion unit PD arranged horizontally
'_2, the output signal from the PD'_4 is read to the vertical signal line 600 _2. That is, the photoelectric conversion units PD′_1 and PD′_3 output the reset transistors RST provided in common to both.
An output signal is read out via the ' ₁ , the amplification transistor SF' ₁ , the selection transistor SEL ' ₁ , and the floating diffusion FD' ₁ . Photoelectric conversion unit PD'_2, PD'_
4, an output signal is read through a reset transistor RST ′ ₂ , an amplification transistor SF ′ ₂ , a selection transistor SEL ′ ₂ , and a floating diffusion FD ′ ₂ which are provided in common to both. Therefore, in the pixel 501, the photoelectric conversion unit PD'_
1, the output signals from PD′_4 have temporal synchronism, and the photoelectric conversion units PD′_2, PD′_
The output signals from 3 have temporal synchrony.

As described above, an output signal having temporal synchronization in the horizontal direction is obtained from the pixel 500, and an output signal having temporal synchronization in the vertical direction is obtained from the pixel 501. However, the circuit configurations of the pixel 500 and the pixel 501 are different from each other.

According to the first embodiment, the following operation and effect can be obtained.
(1) The pixel 200 includes two photoelectric conversion units PD arranged in the row direction and the column direction, and two floating diffusions FD. In the four photoelectric conversion units PD, the photoelectric conversion units PD_1 and PD_3 are sequentially arranged in the row direction, the photoelectric conversion units PD_1 and PD_4 are sequentially arranged in the column direction, and the photoelectric conversion units PD_3 and PD_2 are sequentially arranged in the column direction. You. Photoelectric conversion unit PD_1
And charge generated by the photoelectric conversion unit PD_2 is transferred to the floating diffusion FD _2, charge generated by the photoelectric conversion unit PD_3 and the photoelectric conversion unit PD_4 is floating diffusion FD ₁ transfer. Therefore, the number of transistors required for one pixel can be reduced from 16 to 10 as compared with the conventional technology in which a floating diffusion is provided for each of the four photoelectric conversion units. For this reason, the area of each light receiving surface of the photoelectric conversion unit PD of the present embodiment can be made larger than the area of the light receiving surface of the above-described conventional photoelectric conversion unit. That is, in the present embodiment, it is possible to suppress a decrease in the number of saturated electrons due to a decrease in the area of the light receiving surface and an adverse effect on imaging characteristics due to a decrease in the saturation output due to the decrease. Thus, for example, when the output from the pixel 200 is used for focus detection, it is possible to prevent a decrease in focus detection accuracy.

(2) The pixel 200 includes two photoelectric conversion units PD arranged in each of the row direction and the column direction, and a vertical signal line 300 to which a signal based on charges of the photoelectric conversion unit PD is output. In the four photoelectric conversion units PD, the photoelectric conversion units PD_1 and PD_3 are sequentially arranged in the row direction, the photoelectric conversion units PD_1 and PD_4 are sequentially arranged in the column direction, and the photoelectric conversion units PD_3 and PD_2 are sequentially arranged in the column direction. You.
The signal based on the charges generated by the photoelectric conversion units PD_1 and PD_2 is connected to the vertical signal line 3.
00 ₂ is output to the signal by the charge generated by the photoelectric conversion unit PD_3 and the photoelectric conversion unit PD_4 is output to the vertical signal line 300 _1. Therefore, since the number of components required for one pixel can be reduced, the area of each light receiving surface of the photoelectric conversion unit PD is made larger than the area of the light receiving surface of the photoelectric conversion unit of the related art described above. be able to. That is, similarly to the above-described operation and effect (1), it is possible to suppress the decrease in the number of saturated electrons due to the decrease in the area of the light receiving surface and the adverse effect on the imaging characteristics due to the decrease in the saturation output accompanying the decrease.

(3) The transfer of the charge from the photoelectric conversion unit PD_1 and the transfer of the charge from the photoelectric conversion unit PD_2 are alternatively performed, and the transfer of the charge from the photoelectric conversion unit PD_3 and the charge from the photoelectric conversion unit PD_4. Is performed alternatively. Further, it is possible to output an output signal having temporal synchronization in the horizontal direction or an output signal having temporal synchronization in the vertical direction from the pixels 200 having the same circuit configuration. Therefore, unlike the case where the pixels 500 and 501 are used as in the comparative example, the circuit configuration is different between the output signal having the temporal synchronization in the horizontal direction and the output signal having the temporal synchronization in the vertical direction. Can be prevented from being output signals corresponding to different capacitances.

(4) for the pixel 200 in the first region R1, via the control line 210 to control pulse Vtx_1 is supplied, the transfer of charges in the photoelectric conversion unit PD_1 by the transfer transistor TX1 _2,
And the transfer of charges in the photoelectric conversion unit PD_4 by the transfer transistor TX2 ₁ are carried out simultaneously.
Via control line 220 to control pulse Vtx_2 is supplied, the transfer of charges in the photoelectric conversion unit PD_3 by the transfer transistor TX1 _1, the transfer transistor TX2 ₂ by the photoelectric conversion unit P
The transfer of the charge of D_2 is performed simultaneously.
The control line 21 to which the control pulse Vtx_1 is supplied is supplied to the pixels 200 in the second region R2.
Through 0, and the transfer of charges in the photoelectric conversion unit PD_1 by the transfer transistor TX1 _2, and the transfer of charges in the photoelectric conversion unit PD_3 by the transfer transistor TX1 ₁ are carried out simultaneously. Via control line 220 to control pulse Vtx_2 is supplied, the transfer of charges in the photoelectric conversion unit PD_4 by the transfer transistor TX2 _1, the transfer transistor TX2 ₂ by the photoelectric conversion unit PD_2
Is simultaneously performed. Therefore, unlike the case of the comparative example, from the pixel 200 having the same circuit configuration for reading out the signal, the photoelectric conversion units PD arranged in the vertical direction or the photoelectric conversion units PD arranged in the horizontal direction at the same timing. The output signal can be read.

(5) control lines 210 and 220 are provided in common to the pixel column including a plurality of pixels 200, for pixels 200 in the first region R1, the control lines 210 transfer transistor TX1 ₂
Is connected to TX2 _1, control line 220 is connected to the transfer transistor _TX1 1, TX2 _2. For pixel 200 of the second region R2, the control lines 210 transfer transistor _TX1 2,
Connected to TX1 _1, control line 220 is connected to the transfer transistor _TX2 1, _{TX2 2.} Therefore, the local control lines 211, 221 and 251-2 from the control lines 210 and 220
By making the transfer transistors TX1 and TX2 connected to the
May be included in either the first region R1 or the second region R2. That is, the degree of freedom in the arrangement of the first region R1 and the second region R2 can be improved.

-2nd Embodiment-
A second embodiment of the present invention will be described with reference to the drawings. In the following description, the first
The same components as those of the embodiment are denoted by the same reference numerals, and differences will be mainly described. The points that are not particularly described are the same as in the first embodiment. In the present embodiment, the connection of the local control line connecting the control line and the transfer transistor of the pixel is different from that of the first embodiment.

FIG. 12 is a circuit diagram showing connection at the transistor level of each pixel 200 of the image sensor 101 according to the second embodiment, and is a diagram showing FIG. 2 in detail.
The gate of the transfer transistor TX1 ₂ connected to the photoelectric conversion unit PD_1 of pixel 200,
The local control line 261 is connected to the control line 210 to which the control pulse Vtx_1 is supplied. The gate of the transfer transistor TX1 ₁ connected to the photoelectric conversion unit PD_3 is connected to the control line 220 to control pulse Vtx_2 by the local control line 262 is supplied. The gate of the transfer transistor TX2 ₁ connected to the photoelectric conversion unit PD_4 the local control line 2
63 is connected to the control line 230 to which the control pulse Vtx_3 is supplied. The gate of the transfer transistor TX2 ₂ connected to the photoelectric conversion unit PD_2 is connected to the control line 240 to control pulse Vtx_4 by the local control line 264 is supplied. That is, the pixel 20
0, control pulses Vtx_1, Vtx_2, Vt
The transfer transistors TX1 and TX2 are controlled by x_3 and Vtx_4, respectively.
Other configurations are the same as those of the pixel 200 according to the first embodiment.

(Reading of output signal)
Referring to timing charts shown in FIGS.
The control at the time of reading the output signal from the pixel 200 will be described. FIG. 13 shows a case where an output signal having a temporal synchronization in the vertical direction is read from the photoelectric conversion unit PD (first control). FIG. 5 shows a case where the output signal is read out (second control). In Figure 13, 14, Vtx_1 shows a control pulse of the transfer transistor TX1 ₂ corresponding to the photoelectric conversion unit PD_1 of pixels 200. Vtx_2 shows a control pulse of the transfer transistor TX1 ₁ corresponding to the photoelectric conversion unit Pd_3. Vtx_3 is
Shows the control pulses of the transfer transistors TX2 ₁ corresponding to the photoelectric conversion unit PD_4. Vtx_4
Shows a control pulse of the transfer transistor TX2 ₂ corresponding to the photoelectric conversion unit PD_2.

First, a first method of reading an output signal having temporal temporal synchronization from the photoelectric conversion unit PD is described.
The control will be described. In the following description, differences from the drive timing at the time of reading output signals from the pixels 200 arranged in the first region R1 in the first embodiment will be mainly described.
As shown in FIG. 13, the drive control unit 102a performs the first reset of the potential of the floating diffusion FD in the same manner as in the first embodiment. After a predetermined settling time has elapsed, the vertical signal lines 300 _{1 to} 300 _2n are provided with the pixels 2 of each column by the first reset.
Left photoelectric converter PD_1 in 00, the dark signal for PD_4 "Dark_4 _{1, 1} 2, 4
_{3, 1 4, 4 5,} 1 6, ···, 4 (2n-1), 1 2n "is output at the same time.

Drive control unit 102a turns on the left side of the transfer transistor _TX1 2, TX2 ₁ connected to the photoelectric conversion unit PD_1 and PD_4 pixel 200 switches the Vtx_1 and Vtx_3 to High level at the same timing. In the High level period of Vtx_1,
The signal charges accumulated in the photoelectric conversion unit PD_1 pixels 200 are transferred to the floating diffusion FD _2, the High level period of Vtx_3, the signal charge accumulated in the photoelectric conversion unit PD_4 is transferred to the floating diffusion FD _1. Drive control unit 1
02a turns off the transfer transistor _TX1 2, TX2 ₁ switches the Vtx_1 and Vtx_3 to Low level at the same timing. Thereafter, the potential level of the floating diffusion FD is settled in a predetermined settling time, and becomes a signal level by reading out Vtx_1 and Vtx_3. Each vertical signal lines ₃₀₀ 1 to 300 _2n, the photoelectric conversion unit PD_1 the left in the pixel 200 in each column, signal signals "Sig_4 ₁ for _{PD_4, 1 2, 4 3,} 1 4
, 4 ₅ , ₁₆ ,..., 4 _(2n−1) , _12n ”are output.

The difference between the dark signal and the signal signal output from each vertical signal line 300 is
Are the output signals of the respective photoelectric conversion units PD_1 and PD_4. Therefore, in the plurality of pixels 200 arranged in the same pixel row, the output signals of the photoelectric conversion units PD_1 and PD_4 arranged in the vertical direction have temporal synchronization.

After the signal level is settled, the drive control unit 102a resets the potential of the floating diffusion FD for the second time in the same manner as in the first embodiment. If between predetermined settling time has elapsed, each vertical signal lines ₃₀₀ 1 to 300 _2n, right of the photoelectric conversion unit of the second in the pixel 200 in each column by a reset PD_2, dark signal "Dark_3 ₁ for Pd_3,
_{2 2, 3 3, 2 4} , 3 5, 2 6, ···, 3 (2n-1), 2 2n "is output at the same time.

After settling of the dark level, the drive control unit 102a turns on the transfer transistor _TX1 1, TX2 ₂ switches the Vtx_2 and Vtx_4 to High level at the same timing. In the High level period of the Vtx_2, the signal charges accumulated in the photoelectric conversion unit PD_3 pixels 200 are transferred to the floating diffusion FD _1, the Vtx_4 Hi
In gh level period, the signal charges accumulated in the photoelectric conversion unit PD_2 is transferred to the floating diffusion FD _2. The drive control unit 102a outputs Vtx_2 and Vtx_4
Switch to Low level at the same timing to turn off the transfer transistor _TX1 1, TX2 _2. Thereafter, the potential level of the floating diffusion FD is settled in a predetermined settling time, and becomes a signal level by reading out Vtx_2 and Vtx_4. Each of the vertical signal lines 300 _{1 to} 300 _2n has a photoelectric conversion unit PD_2, PD_
Signal signal for 3 _{'Sig_3 1, 2 2, 3 3} , 2 4, 3 5, 2 6, ···, 3 (2n
_-1) , 2 _2n "is output.

The difference between the dark signal and the signal signal output from each vertical signal line 300 in this manner becomes the output signal of each of the photoelectric conversion units PD_2 and PD_3 in the pixel 200. Therefore,
In the plurality of pixels 200 arranged in the same pixel row, the photoelectric conversion units PD_ arranged in the vertical direction
2. The output signal of PD_3 has temporal synchronization.

Next, a second output signal is read from the photoelectric conversion unit PD, which has an output signal having temporal synchronization in the horizontal direction.
The control will be described. In the following description, differences from the drive timing at the time of reading output signals from the pixels 200 disposed in the second region R2 in the first embodiment will be mainly described.
As shown in FIG. 14, the drive control unit 102a performs a first reset of the potential of the floating diffusion FD in the same manner as in the first embodiment. After a predetermined settling time has elapsed, the vertical signal lines 300 _{1 to} 300 _2n are provided with the pixels 2 of each column by the first reset.
00 upper photoelectric conversion section in PD_1, dark signal "Dark_3 ₁ for PD_3, ₁ 2, 3
_{3, 1 4, 3 5,} 1 6, ···, 3 (2n-1), 1 2n "is output at the same time.

Drive control unit 102a turns on the transfer transistor _TX1 2, TX1 ₁ switches the Vtx_1 and Vtx_2 to High level at the same timing. High of Vtx_1
In level period, the signal charges accumulated in the photoelectric conversion unit PD_1 pixels 200 are transferred to the floating diffusion FD _2, the High level period of Vtx_2,
The signal charges accumulated in the photoelectric conversion unit PD_3 is transferred to the floating diffusion FD _1. The drive control unit 102a sets Vtx_1 and Vtx_2 to Lo at the same timing.
to turn off the transfer transistor _TX1 2, _{TX1 1} switch to w level. Thereafter, the potential level of the floating diffusion FD is settled for a predetermined settling time, and Vtx_1 and Vtx_1
It becomes a signal level by reading out tx_2. Each of the vertical signal lines 300 _{1 to} 300 _2n has a signal signal “Sig” for the upper photoelectric conversion units PD_1 and PD_3 in the pixels 200 in each column.
_{_3 1, 1 2, 3 3} , 1 4, 3 5, 1 6, ···, 3 (2n-1), 1 2n "is output.

The difference between the dark signal and the signal signal output from each vertical signal line 300 in this manner becomes an output signal of each of the photoelectric conversion units PD_1 and PD_3 in the pixel 200. Therefore,
In the plurality of pixels 200 arranged in the same pixel row, the photoelectric conversion units PD_ arranged in the horizontal direction
1. The output signal of PD_3 has temporal synchronization.

After the signal level is settled, the drive control unit 102a resets the potential of the floating diffusion FD for the second time in the same manner as in the first embodiment. If between predetermined settling time has elapsed, each vertical signal lines ₃₀₀ 1 to 300 _2n, the photoelectric conversion portion of the second lower side of the pixel 200 in each column by a reset PD_2, dark signal "Dark_4 ₁ for PD_4,
_{2 2, 4 3, 2 4} , 4 5, 2 6, ···, 4 (2n-1), 2 2n "is output at the same time.

After settling of the dark level, the drive control unit 102a turns on the transfer transistors _TX2 1, TX2 ₂ switches the Vtx_3 and Vtx_4 to High level at the same timing. In the High level period of the Vtx_3, the signal charges accumulated in the photoelectric conversion unit PD_4 pixels 200 are transferred to the floating diffusion FD _1, the Vtx_4 Hi
In gh level period, the signal charges accumulated in the photoelectric conversion unit PD_2 is transferred to the floating diffusion FD _2. The drive control unit 102a outputs Vtx_3 and Vtx_4
Switch to Low level at the same timing to turn off the transfer transistor _TX2 1, _{TX2 2.} Thereafter, the potential level of the floating diffusion FD is settled in a predetermined settling time, and becomes a signal level by reading out Vtx_3 and Vtx_4. Each of the vertical signal lines 300 _{1 to} 300 _2n has a lower photoelectric conversion unit PD_2, PD_ within the pixel 200 of each column.
Signal signal for 4 _{"Sig_4 1, 2 2, 4 3} , 2 4, 4 5, 2 6, ···, 4 (2n
_-1) , 2 _2n "is output.

The difference between the dark signal and the signal signal output from each of the vertical signal lines 300 in this manner becomes an output signal of each of the photoelectric conversion units PD_2 and PD_4 in the pixel 200. Therefore,
In the plurality of pixels 200 arranged in the same pixel row, the photoelectric conversion units PD_ arranged in the horizontal direction
2. The output signal of PD_4 has temporal synchronization.

According to the second embodiment described above, the following operation and effect can be obtained in addition to the operation and effect (1) obtained in the first embodiment.
The control lines 210, 220, 230, and 240 are provided in common for a pixel column including a plurality of pixels 200 arranged in a row direction. Transfer transistors TX1 ₁ , TX1 ₂ , TX2 ₁ , T
X2 ₂ respectively via the local control line 262,261,263,264 control line 220
, 210, 230, 240. The drive control unit 102a controls the control lines 210 and 230
While simultaneously turned on the transfer transistor _TX1 2, TX2 ₁ through the door, the control line 22
0 and simultaneously on to the first control transfer transistor _TX1 1, TX2 ₂ via the 240. The drive control unit 102a controls the transfer transistor TX1 via the control lines 210 and 220.
_2, TX1 ₁ with turning on at the same time, simultaneously on to the second control transfer transistor _TX2 1, TX2 ₂ via the control line 230 and 240. Local control lines 261-26
4, the output signal having the temporal synchronization in the horizontal direction can be output to the pixels 200 having the same circuit configuration including only the connection of the control pulse, or the output having the synchronization in the vertical direction. It is also possible to output a signal.

The following modifications are also within the scope of the present invention, and one or more of the modifications can be combined with the above-described embodiment.
(1) The invention is not limited to one in which four photoelectric conversion units PD are arranged in one pixel 200. For example, two sets of two rows and two columns of photoelectric conversion units PD are arranged as one set, and two sets of photoelectric conversion units PD are arranged in the vertical direction to provide four rows and two columns of photoelectric conversion units PD in one pixel 200; A set of photoelectric conversion units P
D may be arranged in the horizontal direction, and the photoelectric conversion units PD in two rows and four columns may be provided in one pixel 200.

(2) The pixel 200 in which the plurality of photoelectric conversion units PD are arranged is not limited to one in which the pixel 200 is provided in the entire region of the image sensor 101. The pixel 200 may be provided in a partial region of the imaging element 101, and a pixel in which one photoelectric conversion unit is disposed may be disposed in another region. In this case, for example, pixel 2
00 can be provided at the position where the G color filter is provided. When the pixel 200 is provided in a partial area of the image sensor 101, the pixel 200 may not be provided with a color filter. In this case, when the image data for photographing is generated, the image signal at the position of the pixel 200 may be generated by interpolating the image signal with the image signal from the pixels arranged around the pixel 200.

The present invention is not limited to the above embodiments, as long as the features of the present invention are not impaired.
Other modes that can be considered within the scope of the technical idea of the present invention are also included in the scope of the present invention.

DESCRIPTION OF SYMBOLS 1 ... Digital camera, 2 ... Focus detection device, 101 ... Image sensor,
102: body control device, 102a: drive control unit, 102b: focus detection unit,
102c: image processing unit, 200: pixel, 300: vertical signal line,
210, 220, 230, 240 ... control lines,
211, 221, 251, 252, 253, 254, 261, 262, 263, 264 ...
Local control lines,
FD: floating diffusion, TX1, TX2: transfer transistor,
PD: photoelectric conversion unit, RST: reset transistor

Claims (1)

Four photoelectric conversion units disposed two each in a first direction and a second direction intersecting the first direction;
A first and a second charge holding unit to which the charge of the photoelectric conversion unit is transferred,
The four photoelectric conversion units are a first photoelectric conversion unit and a second photoelectric conversion unit sequentially arranged in the first direction, and the first photoelectric conversion unit and a third photoelectric conversion unit arranged sequentially in the second direction. A photoelectric conversion unit, comprising the second photoelectric conversion unit and a fourth photoelectric conversion unit arranged in order in the second direction;
The charge generated by the first photoelectric conversion unit and the fourth photoelectric conversion unit is transferred to the first charge holding unit, and the charge generated by the second photoelectric conversion unit and the third photoelectric conversion unit is An image sensor that is transferred to the second charge holding unit;

Images