KR20200129022A - Image sensor comprising pixel comprising photo diodes - Google Patents

Abstract

Disclosed is an image sensor. The image sensor comprises: a pixel array including a plurality of first pixel groups which include a plurality of pixels placed in a first direction and a second direction; and a row driver providing control signals to the pixel array based on an operation mode. Each of the plurality of pixels includes: a first sub pixel including a first photo diode; a second sub pixel including a second photo diode; and a single micro lens. The first sub pixel and the second sub pixel are placed to be adjacent to each other in a first direction and share a floating diffusion area. The row driver provides control signals for performing an auto focus (AF) function by the unit of pixel in a high-resolution operation mode, and provides the control signals for performing the AF function by the unit of pixel group in a low-resolution mode. The image sensor is able to perform the AF function in various environments.

Description

An image sensor including a pixel including a plurality of photodiodes TECHNICAL FIELD

The technical idea of the present invention relates to an image sensor, and more particularly, to an image sensor including a plurality of pixels including a plurality of photodiodes.

The image sensor includes a pixel array, and each pixel included in the pixel array may include a photodiode. The image sensor is required to perform an auto focus (AF) function so that image capturing can be performed quickly and accurately.

A problem to be solved by the technical idea of the present disclosure is to provide an image sensor capable of performing an AF function in various environments.

An image sensor according to the inventive concept for achieving the above technical problem is a pixel array including a plurality of first pixel groups including a plurality of pixels disposed in a first direction and a second direction, and an operation mode. A row driver that provides control signals to the pixel array based on the pixel array, and each of the plurality of pixels includes a first sub-pixel including a first photodiode, a second sub-pixel including a second photodiode, and one Including a microlens of, the first sub-pixel and the second sub-pixel are disposed adjacent in a first direction and share a floating diffusion region, and the row driver, in the high-resolution operation mode, is a pixel unit of AF (Auto Focus) Control signals are provided to perform a function, and in a low resolution mode, the control signals may be provided to perform an AF function in units of a pixel group, and the resolution in the low resolution mode is less than 1/4 times the resolution in the high resolution mode or Can be the same

An image sensor according to the present invention for achieving the above technical problem includes a pixel array including a plurality of pixel groups including a plurality of pixels arranged in a row direction and a column direction, and first to third modes. A row driver that provides control signals to the pixel array based on the included operation mode, and each of the plurality of pixels includes a first sub-pixel including a first photodiode and a second sub-pixel including a second photodiode And one micro lens, wherein the first sub-pixel and the second sub-pixel are disposed adjacent to each other and share a floating diffusion region, and in the first mode, the row driver performs the AF function on a pixel-by-pixel basis. And, in the second mode, control signals are provided to perform the AF function in units of pixel groups, and in the third mode, control signals are provided to perform the AF function in units of pixels arranged in the same row in one pixel group. can do.

An image sensor according to the present invention for achieving the above technical problem is a pixel array including a plurality of pixel groups including a plurality of pixels disposed in a first direction and a second direction, and a high-resolution mode and a low-resolution mode. And a row driver that provides control signals to the pixel array based on each, and each of the plurality of pixels includes a first subpixel including a first photodiode, a second subpixel including a second photodiode, and one Including a microlens of, the first sub-pixel and the second sub-pixel are disposed adjacent to each other and share a floating diffusion region, and the row driver provides the control signals to perform an AF function in units of pixels in the high-resolution mode. In the low-resolution mode, control signals are provided to perform the AF function for each pixel group, and in the high-resolution mode, all of the plurality of pixels included in the pixel array can perform the AF function.

The image sensor according to the technical idea of the present invention may provide AF functions in various modes by performing an AF function in units of pixels in a high resolution mode and in units of a pixel group in a low resolution mode. In addition, the image sensor can perform high-speed operation by continuously accumulating electric charges generated by a plurality of photodiodes in the floating diffusion region.

1 is a diagram illustrating a structure of a digital imaging device according to an exemplary embodiment of the present disclosure.
Fig. 2 is a block diagram showing a configuration of an image sensor according to an exemplary embodiment of the present disclosure.
3A and 3B are diagrams of a pixel array of an image sensor according to an exemplary embodiment of the present disclosure.
4A to 4C are diagrams of a pixel array of an image sensor according to an exemplary embodiment of the present disclosure.
5 is an exemplary circuit diagram of subpixels sharing a floating diffusion region in an exemplary embodiment according to the present disclosure.
6A to 6E are views for explaining subpixels sharing a floating diffusion region among subpixels included in the first subpixel array of FIG. 3A according to an exemplary embodiment of the present disclosure.
7 is an exemplary circuit diagram of subpixels sharing a floating diffusion region in an exemplary embodiment according to the present disclosure.
8 to 11 are timing diagrams for describing an operation of an image sensor according to an exemplary embodiment of the present disclosure.
12 is a diagram illustrating a pixel array of an image sensor according to an exemplary embodiment of the present disclosure.

1 is a diagram illustrating a structure of a digital imaging device according to an exemplary embodiment of the present disclosure.

Referring to FIG. 1, the digital imaging apparatus 1000 may include an imaging unit 1100, an image sensor 100, and a processor 1200. The digital imaging apparatus 1000 may have a focus detection function.

Operations of the digital imaging apparatus 1000 may be controlled by the processor 1200. The processor 1200 may provide a control signal for the operation of each component to the lens driver 1120, the aperture driver 1140, and the controller 120.

The imaging unit 1100 is a component that receives light, and may include a lens 1110, a lens driving unit 1120, an aperture 1130, and an aperture driving unit 1140. The lens 1110 may include a plurality of lenses.

The lens driver 1120 may communicate information about focus detection with the processor 1200 and may adjust the position of the lens 1110 according to a control signal provided from the processor 1200. The lens driver 1120 may move the lens 1110 in a direction in which the distance from the object 2000 increases or decreases, and the distance between the lens 1110 and the object 2000 may be adjusted. Depending on the position of the lens 1110, the object 2000 may be focused or blurred.

The image sensor 100 may convert incident light into an image signal. The image sensor 100 may include a pixel array 110, a control unit 120, and a signal processing unit 130. The optical signal transmitted through the lens 1110 and the diaphragm 1130 reaches the light-receiving surface of the pixel array 110 to form an image of a subject.

The pixel array 110 may be a Complementary Metal Oxide Semiconductor Image Sensor (CIS) that converts an optical signal into an electrical signal. The sensitivity of the pixel array 110 may be adjusted by the controller 120. The pixel array 110 may include shared pixels for performing an AF function or a distance measurement function.

The processor 1200 may receive a first image signal and a second image signal from the signal processor 130 and perform a phase difference operation using the first image signal and the second image signal. The processor 1200 may obtain a position of a focus, a direction of a focus, or a distance between the object 2000 and the image sensor 100 as a result of the phase difference calculation. The processor 1200 may output a control signal to the lens driving unit 1120 to move the position of the lens 1110 based on the result of the phase difference calculation.

Fig. 2 is a block diagram showing a configuration of an image sensor according to an exemplary embodiment of the present disclosure.

Referring to FIG. 2, the image sensor 100 may include a pixel array 110, a control unit 120, a signal processing unit 130, a row driver 140, and a signal reading unit 150. The signal readout unit 150 may include a Correlated-Double Sampling Circuit (CDS) 151, an analog-digital converter (ADC) 153, and a buffer 155.

The pixel array 110 may include a first sub-pixel array 110_1 and a second sub-pixel array 110_2. In an exemplary embodiment, the first sub-pixel array 110_1 may include a plurality of pixels PX_X capable of performing an AF function in a first direction (eg, a row direction), and a second sub-pixel array 110_1 The pixel array 110_2 may include a plurality of pixels PX_Y capable of performing an AF function in a second direction (eg, a color direction).

The plurality of pixels PX_X of the first sub-pixel array 110_1 may each include two photodiodes disposed in parallel in the first direction and one microlens disposed on the two photodiodes, respectively. . The plurality of pixels PX_Y of the second sub-pixel array 110_2 may each include two photodiodes disposed in parallel in a second direction and one microlens disposed on the two photodiodes, respectively. . Accordingly, each of the plurality of pixels PX_X of the first sub-pixel array 110_1 may perform an AF function in the first direction, and each of the plurality of pixels PX_Y of the second sub-pixel array 110_2 is The AF function in the second direction can be performed. Since each of the plurality of pixels PX_X and PX_Y included in the pixel array 110 includes two photodiodes and one micro lens, each of the plurality of pixels PX_X and PX_Y is a pixel for performing an AF function. Can generate signals. Accordingly, the image sensor according to the present disclosure may provide an improved AF function.

In an exemplary embodiment, a width of each of the plurality of pixels PX_X of the first sub-pixel array 110_1 and the plurality of pixels PX_Y of the second sub-pixel array 110_2 may be 0.5 μm or more and 1.8 μm or less. have. Alternatively, in an exemplary embodiment, the width of each of the plurality of pixels PX_X and PX_Y may be 0.64 μm or more and 1.4 μm or less.

The plurality of pixels PX_X of the first sub-pixel array 110_1 and the plurality of pixels PX_Y of the second sub-pixel array 110_2 may be grouped into pixel groups, and the image sensor 100 is By performing the AF function in a pixel group unit instead of a pixel unit in an environment of, it is possible to operate in a low-resolution mode. A detailed configuration of each of the first sub-pixel array 110_1 and the second sub-pixel array 110_2 will be described in detail with reference to FIGS. 3A and 3B.

The pixel array 110 may output a pixel signal (eg, VOUT of FIG. 5) to the CDS 151 through the first to n-1th column output lines CLO_0 to CLO_n-1. Pixel signals output from the plurality of pixels PX_X of the first sub-pixel array 110_1 and the plurality of pixels PX_Y of the second sub-pixel array 110_2 are phase signals used to calculate a phase difference. I can. The phase signals may include information about positions of images formed on the image sensor 100, and a focus position of the lens 1110 (FIG. 1) may be calculated based on the calculated phase differences. For example, the position of the lens 1110 (FIG. 1) that makes the phase difference to 0 may be the focus position. In an exemplary embodiment, in the high-resolution mode, a plurality of pixels (eg, PX_X, PX_Y) constituting the pixel array 110 may all perform an AF function.

The plurality of pixels PX_X of the first sub-pixel array 110_1 and the plurality of pixels PX_Y of the second sub-pixel array 110_2 not only focus on the object, but also the object 2000 and the image sensor ( 100) can also be used to measure the distance between. In order to measure the distance between the object 2000 and the image sensor 100, phase differences between the images formed on the image sensor 100, the distance between the lens 1110 and the image sensor 100, the lens 1110 Additional information such as the size of and the focal position of the lens 1110 may be referred to.

The control unit 120 causes the pixel array 110 to absorb light to accumulate electric charge, temporarily stores the accumulated electric charge, and outputs an electrical signal according to the stored electric charge to the outside of the pixel array 110, The row driver 140 can be controlled. In addition, the controller 120 may control the signal reader 150 to measure the level of a pixel signal provided by the pixel array 110.

The row driver 140 may generate control signals RSs, TSs, and SELSs for controlling the pixel array 110 and provide them to the pixel array 110. In an exemplary embodiment, based on whether to perform an AF function or a distance measurement function, the row driver 140 is configured to display a plurality of pixels PX_X and a second sub-pixel array 110_2 of the first sub-pixel array 110_1. Activation and deactivation timing of reset control signals RSs, transmission control signals TSs, and selection signals SELSs provided to each of the plurality of pixels PX_Y of) may be determined.

The CDS 151 may sample and hold a pixel signal provided by the pixel array 110. The CDS 151 may double sample a specific noise level and a level according to a pixel signal, and output a level corresponding to the difference. In addition, the CDS 151 may receive a ramp signal generated by the ramp signal generator 157 and compare with each other to output a comparison result. The analog-to-digital converter 153 may convert an analog signal corresponding to a level received from the CDS 151 into a digital signal. The buffer 155 may latch a digital signal, and the latched signals may be sequentially output to the outside of the signal processing unit 130 or the image sensor 100.

The signal processing unit 130 may perform signal processing based on the digital signal received from the buffer 155. For example, the signal processing unit 130 may perform noise reduction processing, gain adjustment, waveform shaping processing, interpolation processing, white balance processing, gamma processing, edge enhancement processing, and the like. Also, the signal processing unit 130 may output signal-processed information to the processor 1200 during the AF operation to perform a phase difference operation for the AF operation. In an exemplary embodiment, the signal processing unit 130 may be provided in the processor 1200 (FIG. 1) outside the image sensor 100.

3A and 3B are diagrams of a pixel array of an image sensor according to an exemplary embodiment of the present disclosure. FIG. 3A is a diagram illustrating an exemplary embodiment of a first sub-pixel array included in the pixel array of FIG. 2, and FIG. 3B is a diagram illustrating an exemplary embodiment of a second sub-pixel array included in the pixel array of FIG. 2 to be.

Referring to FIG. 3A, a first sub-pixel array 110_1 is arranged in a row direction (eg, a first direction (X)) and a column direction (eg, a second direction (Y)). It may include pixels PX_X. Each of the plurality of pixels PX_X may include one micro lens ML.

The first sub-pixel array 110_1 may include first to fourth pixel groups PG1 to PG4. The first pixel group PG1 and the second pixel group PG2 may be disposed in parallel in the first direction X, and the third pixel group PG3 and the fourth pixel group PG4 are in the first direction ( X) can be arranged side by side. The first pixel group PG1 and the third pixel group PG3 may be arranged side by side in the second direction Y, and the second pixel group PG2 and the fourth pixel group PG4 are in the second direction ( Y) can be arranged side by side.

In an exemplary embodiment, each of the first to fourth pixel groups PG1 to PG4 may include four pixels PX_X, but the present disclosure is not limited thereto. For example, each of the first to fourth pixel groups PG1 to PG4 may include 8 subpixels arranged in 2 rows and 4 columns. For example, the first pixel group PG1 may include first to eighth subpixels SPX11 to SPX18, and the first subpixel SPX11 and the second subpixel SPX12 are one pixel ( PX_X), and the third sub-pixel SPX13 and the fourth sub-pixel SPX14 may constitute one pixel PX_X, and the fifth sub-pixel SPX15 and the sixth sub-pixel SPX16 ) May constitute one pixel PX_X, and the seventh sub-pixel SPX17 and the eighth sub-pixel SPX18 may constitute one pixel PX_X. In addition, for example, the second pixel group PG2 may include first to eighth subpixels SPX21 to SPX28, and the third pixel group PG3 is the first to eighth subpixels SPX31 to SPX38), and the fourth pixel group PG4 may include first to eighth subpixels SPX41 to SPX48. That is, one pixel PX_X may include two subpixels disposed adjacent to each other in the first direction X.

The first sub-pixel array 110_1 may include a color filter so that the plurality of pixels PX_X can sense various colors. In an exemplary embodiment, the color filter may include filters for sensing red (R), green (G), and blue (B), and each of the first to fourth pixel groups PG1 to PG4 is the same color filter. It may include pixels PX_X including.

In an exemplary embodiment, the first to fourth pixel groups PG1 to PG4 may be disposed on the first sub-pixel array 110_1 to correspond to a Bayer pattern. For example, the first pixel group PG1 and the fourth pixel group PG4 may include a green (G) color filter, and the second pixel group PX2 may include a red (R) color filter. In addition, the third pixel group PG3 may include a blue (B) color filter.

However, this is only an embodiment, and the first sub-pixel array 110_1 according to the embodiment of the present invention may include various types of color filters. For example, the color filter may include filters for sensing yellow, cyan, and magenta colors. Alternatively, the color filter may include filters that sense white color.

Each of the plurality of subpixels SPX11 to SPX18, SPX21 to SPX28, SPX31 to SPX38, and SPX41 to SPX48 included in the first subpixel array 110_1 may include a corresponding photodiode. Accordingly, each of the plurality of pixels PX_X may include photodiodes disposed adjacent to each other in the first direction X and microlenses ML disposed on the photodiodes. Depending on the shape and refractive index of the micro lens ML, the amount of photocharge generated by the photodiodes included in one pixel PX_X may vary. The AF function in the first direction X may be performed based on a pixel signal corresponding to an amount of photocharge generated by each of the photodiodes included in one pixel PX_X. For example, using a pixel signal output by the first sub-pixel SPX11 of the first pixel group PG1 and a pixel signal output by the second sub-pixel SPX12 of the first pixel group PG1 AF function can be performed. Accordingly, the image sensor according to the present disclosure may perform an AF function in units of pixels in a first mode, that is, a high resolution mode. In an exemplary embodiment, in the high-resolution mode, all of the plurality of pixels PX_X included in the first sub-pixel array 110_1 may perform the AF function.

On the other hand, the image sensor according to the present disclosure may perform an AF function in pixel group units in the second mode, that is, a low resolution mode. For example, generated by photodiodes of each of the first sub-pixel SPX11, the third sub-pixel SPX13, the fifth sub-pixel SPX15, and the seventh sub-pixel SPX17 of the first pixel group PG1. The pixel signal corresponding to the amount of photocharge, and each of the second sub-pixel SPX12, the fourth sub-pixel SPX14, the sixth sub-pixel SPX16, and the eighth sub-pixel SPX18 of the first pixel group PG1 The AF function may be performed by processing a pixel signal corresponding to the amount of photocharge generated by the photodiode. Therefore, even if the amount of light irradiated by the image sensor is small and the amount of charge generated by one photodiode is insufficient, as in a low-light situation, the AF function in the first direction (X) can be performed using the amount of charge generated by the plurality of photodiodes I can. In an exemplary embodiment, the resolution in the low resolution mode may be less than or equal to 1/4 times the resolution in the high resolution mode.

Alternatively, the image sensor according to the present disclosure may perform an AF function in units of a plurality of pixels PX_X included in one pixel group and disposed in the same row in a third mode, that is, a medium resolution mode. For example, a pixel signal corresponding to an amount of photocharge generated by the photodiodes of each of the first sub-pixel SPX11 and the third sub-pixel SPX13 of the first pixel group PG1, and the first pixel group PG1 The AF function may be performed by processing a pixel signal corresponding to an amount of photocharge generated by the photodiodes of each of the second subpixel SPX12 and the fourth subpixel SPX14 of. In an exemplary embodiment, the resolution in the medium resolution mode may be greater than 1/4 times the resolution in the high resolution mode and less than or equal to 1/2 times the resolution in the high resolution mode.

Alternatively, the image sensor according to the present disclosure may perform an AF function in units of a plurality of pixels PX_X included in one pixel group and disposed in the same column in a third mode, that is, a medium resolution mode. For example, a pixel signal corresponding to an amount of photocharge generated by the photodiodes of each of the first sub-pixel SPX11 and the fifth sub-pixel SPX15 of the first pixel group PG1, and the first pixel group PG1 The AF function may be performed by calculating a pixel signal corresponding to the amount of photocharge generated by the photodiodes of each of the second and sixth subpixels SPX12 and SPX16 of.

Referring to FIG. 3B, the second sub-pixel array 110_2 may include a plurality of pixels PX_Y arranged along a first direction X and a second direction Y. Each of the plurality of pixels PX_Y may include one micro lens ML.

The second sub-pixel array 110_2 may include first to fourth pixel groups PG1Y to PG4Y. In an exemplary embodiment, each of the first to fourth pixel groups PG1Y to PG4Y may include four pixels PX_Y, but the present disclosure is not limited thereto. For example, the first pixel group PG1Y may include first to eighth sub-pixels SPX11Y to SPX18Y, and the first sub-pixel SPX11Y and the second sub-pixel SPX12Y are one pixel ( PX_Y) can be configured, and the third sub-pixel SPX13Y and the fourth sub-pixel SPX14Y can constitute one pixel PX_Y, and the fifth sub-pixel SPX15Y and the sixth sub-pixel SPX16Y ) May constitute one pixel PX_Y, and the seventh sub-pixel SPX17Y and the eighth sub-pixel SPX18Y may constitute one pixel PX_Y. Also, for example, the second pixel group PG2Y may include first to eighth subpixels SPX21Y to SPX28Y, and the third pixel group PG3Y may include first to eighth subpixels SPX31Y to SPX38Y), and the fourth pixel group PG4Y may include first to eighth subpixels SPX41Y to SPX48Y. That is, one pixel PX_X may include two sub-pixels disposed adjacent to each other in the second direction Y.

The second sub-pixel array 110_2 may include a color filter so that the plurality of pixels PX_Y can sense various colors. In an exemplary embodiment, the color filter may include filters that sense red (R), green (G), and blue (B), and each of the first to fourth pixel groups PG1Y to PG4Y is the same color filter. It may include pixels PX_Y including.

In an exemplary embodiment, the first to fourth pixel groups PG1Y to PG4Y may be disposed in the second sub-pixel array 110_2 to correspond to the Bayer pattern. For example, the first pixel group PG1Y and the fourth pixel group PG4Y may include a green (G) color filter, and the second pixel group PX2Y may include a red (R) color filter. In addition, the third pixel group PG3Y may include a blue (B) color filter.

However, this is only an exemplary embodiment, and the second sub-pixel array 110_2 according to an exemplary embodiment of the present invention may include various types of color filters. For example, the color filter may include filters for sensing yellow, cyan, and magenta colors. Alternatively, the color filter may include filters that sense white color.

Each of the plurality of sub-pixels SPX11Y to SPX18Y, SPX21Y to SPX28Y, SPX31Y to SPX38Y, and SPX41Y to SPX48Y included in the second sub-pixel array 110_2 may include one photodiode. Accordingly, each of the plurality of pixels PX_Y may include photodiodes disposed adjacent to each other in the second direction Y and microlenses ML disposed on the photodiodes. Depending on the shape and refractive index of the micro lens ML, the amount of photocharge generated by the photodiodes included in one pixel PX_Y may vary. The AF function in the second direction Y may be performed based on a pixel signal corresponding to an amount of photocharge generated by each of the photodiodes included in one pixel PX_Y. For example, using the pixel signal output by the first sub-pixel SPX11Y of the first pixel group PG1Y and the pixel signal output by the second sub-pixel SPX12Y of the first pixel group PG1Y AF function can be performed. Accordingly, the image sensor according to the present disclosure may perform an AF function in the second direction Y in pixel units in a high resolution mode.

On the other hand, the image sensor according to the present disclosure may perform an AF function in a pixel group unit in a low resolution mode. For example, generated by photodiodes of each of the first sub-pixel SPX11Y, the third sub-pixel SPX13Y, the fifth sub-pixel SPX15Y, and the seventh sub-pixel SPX17Y of the first pixel group PG1Y. The pixel signal corresponding to the amount of photocharge, and each of the second sub-pixel SPX12Y, the fourth sub-pixel SPX14Y, the sixth sub-pixel SPX16Y, and the eighth sub-pixel SPX18Y of the first pixel group PG1Y The AF function in the second direction Y may be performed by processing a pixel signal corresponding to the amount of photocharge generated by the photodiode. In an exemplary embodiment, the resolution in the low resolution mode may be less than or equal to 1/4 times the resolution in the high resolution mode.

Alternatively, the image sensor according to the present disclosure may be included in one pixel group in the medium resolution mode and may perform an AF function in units of a plurality of pixels PX_Y arranged in the same row. For example, a pixel signal corresponding to the amount of photocharge generated by the photodiodes of each of the first sub-pixel SPX11Y and the third sub-pixel SPX13Y of the first pixel group PG1Y, and the first pixel group PG1Y The AF function may be performed by processing a pixel signal corresponding to an amount of photocharge generated by each photodiode of the second sub-pixel SPX12Y and the fourth sub-pixel SPX14Y of. In an exemplary embodiment, the resolution in the medium resolution mode may be greater than 1/4 times the resolution in the high resolution mode and less than or equal to 1/2 times the resolution in the high resolution mode.

Alternatively, the image sensor according to the present disclosure may be included in one pixel group in the medium resolution mode and may perform the AF function in units of a plurality of pixels PX_Y arranged in the same column. For example, a pixel signal corresponding to the amount of photocharge generated by the photodiodes of each of the first sub-pixel SPX11Y and the fifth sub-pixel SPX15Y of the first pixel group PG1Y, and the first pixel group PG1Y The AF function may be performed by processing a pixel signal corresponding to an amount of photocharge generated by each photodiode of the second sub-pixel SPX12Y and the sixth sub-pixel SPX16Y of.

4A to 4C are diagrams of a pixel array of an image sensor according to an exemplary embodiment of the present disclosure, and are diagrams illustrating an exemplary embodiment of a first subpixel array included in the pixel array. For the same reference numerals as in FIG. 3A, redundant descriptions will be omitted in FIGS.

Referring to FIG. 4A, the first sub-pixel array 110_1a may include a color filter so that a plurality of pixels PX_X sense various colors. In an exemplary embodiment, the color filter may include filters that sense red (R), green (G), blue (B), white (W), and yellow (Y). In an exemplary embodiment, each of the first to fourth pixel groups PG1a to PG4a may include color filters having different colors therein.

The first pixel group PG1a and the fourth pixel group PG4a may include a green (G) color filter and a white (W) color filter. For example, the seventh sub-pixel SPX17 and the eighth sub-pixel SPX18 of the first pixel group PG1a may include a white (W) color filter, and the first pixel group of the fourth pixel group PG4a The sub-pixel SPX41 and the second sub-pixel SPX42 may include a white (W) color filter. Alternatively, the first pixel group PG1a and the fourth pixel group PG4a may include a green (G) color filter and a yellow (Y) color filter.

The second pixel group PG2a may include a red (R) color filter and a white (W) color filter. For example, the fifth sub-pixel SPX25 and the sixth sub-pixel SPX26 of the second pixel group PG2a may include a white (W) color filter. Alternatively, the second pixel group PG2a may include a red (R) color filter and a yellow (Y) color filter.

The third pixel group PG3a may include a blue (B) color filter and a white (W) color filter. For example, the third sub-pixel SPX33 and the fourth sub-pixel SPX34 of the third pixel group PG3a may include a white (W) color filter. Alternatively, the second pixel group PG2a may include a red (R) color filter and a yellow (Y) color filter.

In an exemplary embodiment, pixels PX_X including a white (W) color filter may be disposed adjacent to each other in the first to fourth pixel groups PG1a to PG4a. Alternatively, pixels PX_X including a yellow (Y) color filter in the first to fourth pixel groups PG1a to PG4a may be disposed adjacent to each other.

Referring to FIG. 4B, each of the first to fourth pixel groups PG1 to PG4b may include pixels PX_X including the same color filter. For example, the first pixel group PG1 includes a green (G) color filter, the second pixel group PG2 includes a red (R) color filter, and the third pixel group PG3 is blue ( B) A color filter is included, and the fourth pixel group PG4 may include a white (W) color filter or a yellow (Y) color filter.

Referring to FIG. 4C, each of the first to fourth pixel groups PG1c to PG4c may include color filters having different colors therein. The first pixel group PG1c and the fourth pixel group PG4c may include a green (G) color filter and a white (W) color filter, or may include a green (G) color filter and a yellow (Y) color filter. have. For example, the first, second, seventh, and eighth subpixels (SPX11, SPX12, SPX17, SPX18, SPX41, SPX42, SPX47, SPX48) of the first pixel group PG1c and the fourth pixel group PG4c May include a white (W) color filter or a yellow (Y) color filter. Further, for example, the third, fourth, fifth and sixth subpixels SPX13, SPX14, SPX15, SPX16, SPX43, SPX44, SPX45 of the first pixel group PG1c and the fourth pixel group PG4c, SPX46) may include a green (G) color filter.

The second pixel group PG2c may include a red (R) color filter and a white (W) color filter, or may include a red (R) color filter and a yellow (Y) color filter. For example, the first, second, seventh and eighth subpixels SPX21, SPX22, SPX27, SPX28 of the second pixel group PG2c include a white (W) color filter or a yellow (Y) color filter. The third, fourth, fifth and sixth subpixels SPX23, SPX24, SPX25, and SPX26 may include a red (R) color filter.

The third pixel group PG3c may include a blue (B) color filter and a white (W) color filter, or may include a blue (B) color filter and a yellow (Y) color filter. For example, the first, second, seventh and eighth sub-pixels SPX31, SPX32, SPX37, SPX38 of the third pixel group PG3c include a white (W) color filter or a yellow (Y) color filter. The third, fourth, fifth and sixth sub-pixels SPX33, SPX34, SPX35, and SPX36 may include a blue (B) color filter.

FIG. 5 is an exemplary circuit diagram of sub-pixels sharing a floating diffusion region in an exemplary embodiment according to the present disclosure. In FIG. 5, exemplary embodiments of forming a shared pixel structure in which a first sub-pixel and a second sub-pixel included in the first pixel group share a floating diffusion region are described, but the same description is applied to other sub-pixels. Can be applied.

Referring to FIG. 5, a first sub-pixel may include a first photodiode PD11, a first transfer transistor TX11, a selection transistor SX, a drive transistor SF, and a reset transistor RX. . The second sub-pixel may include a second photodiode PD12, a second transfer transistor TX12, a selection transistor SX, a drive transistor SF, and a reset transistor RX. The first sub-pixel and the second sub-pixel share a floating diffusion region FD1 with each other, and share a selection transistor SX, a drive transistor SF, and a reset transistor RX. Can be formed. In an exemplary embodiment, at least one of the selection transistor SX, the drive transistor SF, and the reset transistor RX may be omitted.

Each of the first photodiode PD11 and the second photodiode PD12 may generate photocharges that vary according to the intensity of light. For example, each of the first photodiode PD11 and the second photodiode PD12 is a PN junction diode, which generates electric charges, that is, electrons that are negative charges and holes that are positive charges, in proportion to the amount of incident light. I can. Each of the first photodiode PD11 and the second photodiode PD12 is an example of a photoelectric conversion device, such as a photo transistor, a photo gate, a pinned photo diode (PPD), and It may be at least one of these combinations.

The first transfer transistor TX11 may transfer the photo charge generated by the first photodiode PD11 to the floating diffusion region FD1 according to the first transfer control signal TS11. When the first transfer transistor TX11 is turned on, photo charges generated by the first photodiode PD11 may be transferred to the floating diffusion region FD1, and the floating diffusion region FD1 ) Can be accumulated and stored. The second transfer transistor TX12 may transfer the photo charge generated by the first photodiode PD12 to the floating diffusion region FD1 according to the second transfer control signal TS12.

The floating diffusion region FD1 may operate as a capacitor. Accordingly, as the number of photodiodes connected to the floating diffusion region FD1 increases, the floating diffusion region FD1 may require a large capacitance.

The reset transistor RX may periodically reset charges accumulated in the floating diffusion region FD1. The source electrode of the reset transistor RX may be connected to the floating diffusion region FD1, and the drain electrode may be connected to the power voltage VPIX. When the reset transistor RX is turned on according to the reset control signal RS1, the power voltage VPIX connected to the drain electrode of the reset transistor RX is transferred to the floating diffusion region FD1. When the reset transistor RX is turned on, charges accumulated in the floating diffusion region FD1 are discharged, so that the floating diffusion region FD1 may be reset.

The drive transistor SF may be controlled according to the amount of photo charges accumulated in the floating diffusion region FD1. The drive transistor SF is a buffer amplifier and may buffer a signal according to charges charged in the floating diffusion region FD1. The drive transistor SF amplifies the potential change in the floating diffusion region FD1 and converts it to a column output line (eg, among the first to n-1th column output lines CLO_0 to CLO_n-1 in FIG. 2 ). One column output line) may be output as a pixel signal VOUT.

The selection transistor SX has a drain terminal connected to the source terminal of the drive transistor SF, and in response to the selection signal SELS1, the pixel signal (for example, 151 in FIG. 2) through the column output line VOUT) can be output.

The first transmission control signal TS11, the second transmission control signal TS12, the reset control signal RS1, and the selection signal Sels1 shown in FIG. 5 are a row driver (for example, 140 in FIG. 2). These may be control signals provided to the pixel array 110 to control the array (eg, 110 in FIG. 2 ).

6A to 6E are views for explaining subpixels sharing a floating diffusion region among subpixels included in the first subpixel array of FIG. 3A according to an exemplary embodiment of the present disclosure. 6A to 6E illustrate the first sub-pixel array of FIG. 3A, but the second sub-pixel array of FIG. 3B and the first sub-pixel array of FIGS. 4A to 4C are also Description may apply.

Referring to FIG. 6A, the first sub-pixel array 100_1e may include first to fourth pixel groups PG1e to PG4e, and each of the first to fourth pixel groups PG1e to PG4e is a plurality of pixels. They may include (PX_X). A shared pixel structure SHPX1 in which subpixels included in each of the plurality of pixels PX_X share a floating diffusion region with each other may be formed. That is, the shared pixel structure SHPX1 may be a 2-Shared structure including two sub-pixels, and one floating diffusion region may be shared for every two sub-pixels.

For example, the first sub-pixel SPX11 and the second sub-pixel SPX12 of the first pixel group PG1e form one shared pixel structure SHPX1 that shares a floating diffusion region, and the first pixel The third sub-pixel SPX13 and the fourth sub-pixel SPX14 of the group PG1e may form one shared pixel structure SHPX1 that shares a floating diffusion region. In this case, the first sub-pixel SPX11 and the third sub-pixel SPX13 may include different floating diffusion regions. The description of the first pixel group PG1e may also be applied to the second to fourth pixel groups PG2e to PG4e.

In an exemplary embodiment, the first sub-pixel array 100_1e may accumulate all photo charges generated from two different photodiodes in one floating diffusion region in a high resolution mode. For example, the first sub-pixel array 100_1e outputs the reset voltage as a pixel signal (for example, VOUT in FIG. 5), and then outputs the pixel signal VOUT by the first sub-pixel SPX11. , A pixel signal VOUT by the first sub-pixel SPX11 and the second sub-pixel SPX12 may be output. That is, the subpixels constituting one pixel (eg, the first subpixel SPX11 and the second subpixel SPX12) share a floating diffusion region (eg, FD1 in FIG. 5). , Photo charges generated by the first photodiode (eg, PD11 of FIG. 5) of the first subpixel SPX11 and the second photodiode of the second subpixel SPX12 (eg, PD12 of FIG. 5) The pixel signal VOUT according to the photo charge generated in) may be output. Such a lead-out method may be a RSSRSSRSSRSS (reset-signal-signal-reset-signal-signal-reset-signal-signal-reset-signal-signal) lead-out method.

However, the operation of the image sensor including the first sub-pixel array 100_1e in the high resolution mode according to the present disclosure is not limited thereto. Even if the first sub-pixel SPX11 and the second sub-pixel SPX12 share the floating diffusion region FD1, the first sub-pixel array 100_1e is a pixel signal VOUT from the first sub-pixel SPX11. After is output, the floating diffusion region FD1 is reset to output the reset voltage as a pixel signal VOUT, and thereafter, the pixel signal VOUT by the second sub-pixel SPX12 may be output. Such a read-out method may be a RSRSRSRSRSRSRS (reset-signal-reset-signal-reset-signal-reset-signal-reset-signal-reset-signal-reset-signal-reset-signal) lead-out method. The image sensor according to the present disclosure resets the floating diffusion region in acquiring a pixel signal VOUT output from each of the subpixels included in one shared pixel structure SHPX1 that shares one floating diffusion region. You can configure the number of times. As the number of resets of the floating diffusion region increases, the time it takes to acquire all of the pixel signals VOUT output from each of the sub-pixels included in one shared pixel structure (SHPX1) increases, but has a relatively small capacitance. A floating diffusion region of can be formed, and a conversion gain can be increased. On the other hand, as the number of resets of the floating diffusion area decreases, a floating diffusion area having a large capacitance may be required, but the pixel signal VOUT output from each of the subpixels included in one shared pixel structure SHPX1 is The time it takes to acquire all can be reduced.

In an exemplary embodiment, each of the first to fourth pixel groups PG1e to PG4e included in the first subpixel array 100_1e is a different column output line (for example, the first to n-1th column outputs) Each of the lines CLO_0 to CLO_n-1 may be connected to a corresponding column output line. For example, a plurality of pixels PX_X included in the first pixel group PG1e are connected to the first column output line CLO_0, and a plurality of pixels PX_X included in the second pixel group PG2e ) Is connected to the second column output line CLO_1, and the plurality of pixels PX_X included in the third pixel group PG3e are connected to the third column output line CLO_2, and are connected to the fourth pixel group PG4e. A plurality of pixels PX_X included in) may be connected to the fourth column output line CLO_3.

In this case, the image sensor including the first sub-pixel array 100_1e may perform an analog pixel binning operation in a low resolution mode. For example, in the low-resolution mode, the first sub-pixel array 100_1e outputs the reset voltage as a pixel signal VOUT through the first column output line CLO_0, and then outputs the first, third, fifth, and The pixel signal VOUT by the 7 sub-pixels SPX11, SPX13, SPX15, SPX17 can be output to the first column output line CLO_0, and thereafter, the first to eighth sub-pixels SPX11 to SPX18 The pixel signal VOUT may be output to the first column output line CLO_0. Such a lead-out method may be a reset-signal-signal (RSS) lead-out method.

Alternatively, the first sub-pixel array 100_1e outputs the reset voltage as a pixel signal VOUT through the first column output line CLO_0 in a low resolution mode, and then outputs the first, third, fifth, and seventh sub-pixels. The pixel signal VOUT by the pixels SPX11, SPX13, SPX15, and SPX17 can be output to the first column output line CLO_0, and after that, the reset voltage is again applied to the pixel signal through the first column output line CLO_0. After outputting to (VOUT), the pixel signal VOUT by the second, fourth, sixth and eighth sub-pixels (SPX12, SPX14, SPX16, SPX18) can be output to the first column output line (CLO_0). have. Such a read-out method may be a reset-signal-reset-signal (RS-RS) read-out method.

However, image sensors according to the present disclosure are not limited thereto, and each of the plurality of pixels PX_X included in the first sub-pixel array 100_1e may be connected to different column output lines. In this case, the image sensor including the first sub-pixel array 100_1e may perform a digital pixel binning operation in a low resolution mode. For example, the first sub-pixel array 100_1e receives different pixel signals VOUT by each of the first, third, fifth and seventh sub-pixels SPX11, SPX13, SPX15, and SPX17 in a low resolution mode. Each pixel signal VOUT can be output through different column output lines, and each pixel signal VOUT is converted into a digital signal by CDS (e.g., 151 in Fig. 2) and ADC (e.g., 153 in Fig. 2). And stored in a buffer (eg, 155 of FIG. 2 ). The buffer 155 receives data corresponding to the pixel signals output from each of the first, third, fifth and seventh subpixels SPX11, SPX13, SPX15, and SPX17 as one signal, and a signal processing unit (e.g., FIG. 2 of 130) or to the outside of the image sensor. After that, the buffer 155 uses the data corresponding to the pixel signals output from each of the second, fourth, sixth, and eighth subpixels SPX12, SPX14, SPX16, and SPX18 as one signal, and the signal processing unit 130 or It can be output to the outside of the image sensor. Accordingly, the image sensor including the first sub-pixel array 100_1e may perform an AF function in units of pixels in a high resolution mode, and may perform an AF function in units of pixel groups in a low resolution mode.

In an exemplary embodiment, in the medium resolution mode, the image sensor including the first sub-pixel array 100_1e may perform an analog pixel binning operation or a digital pixel binning operation. Accordingly, the image sensor including the first sub-pixel array 100_1e can perform an AF function in units of pixels in a high resolution mode, and can perform an AF function in units of a pixel group in a low resolution mode, depending on the illumination environment. A high-resolution mode, a low-resolution mode, and a medium-resolution mode can be provided.

Referring to FIG. 6B, the first sub-pixel array 100_1f may include first to fourth pixel groups PG1f to PG4f, and each of the first to fourth pixel groups PG1f to PG4f is a plurality of pixels. They may include (PX_X). Among the plurality of pixels PX_X, pixels PX_X disposed adjacent to each other in the first direction X may form a shared pixel structure SHPX2X sharing a floating diffusion region. That is, the shared pixel structure SHPX2X may be a 4-Shared structure including four sub-pixels, and a shared pixel structure SHPX2X sharing a floating diffusion region for every four sub-pixels may be formed.

The image sensor including the first sub-pixel array 100_1f may perform an AF function in a unit of each of the plurality of pixels PX_X, that is, a pixel unit in a high resolution mode, and the first to fourth pixels in a low resolution mode. The AF function may be performed in units of each of the pixel groups PG1f to PG4f, that is, in units of pixel groups. For example, in the high resolution mode, the first sub-pixel array 100_1f may output the pixel signal VOUT using the aforementioned RSSRSSRSSRSS readout method. Alternatively, the pixel signal VOUT may be output in the RSRSRSRSRSRS readout method.

Alternatively, the first sub-pixel array 100_1f may accumulate all photo charges generated from four different photodiodes in one floating diffusion region in a high resolution mode. For example, the first sub-pixel array 100_1f outputs a reset voltage as a pixel signal VOUT, and then outputs a pixel signal VOUT by the first sub-pixel SPX11, and the first sub-pixel SPX11 ) And the pixel signal VOUT by the second sub-pixel SPX12, outputting the pixel signal VOUT by the first to third sub-pixels SPX11 to SPX13, and the first to fourth sub-pixels The pixel signal VOUT by (SPX11 to SPX14) can be output. Such a lead-out method may be a RSSSSRSSSS (reset-signal-signal-signal-signal-reset-signal-signal-signal-signal) lead-out method.

Alternatively, for example, in the high resolution mode, the first sub-pixel array 100_1f outputs a reset voltage as a pixel signal VOUT, and then outputs a pixel signal VOUT by the first sub-pixel SPX11, The pixel signal VOUT by the first sub-pixel SPX11 and the second sub-pixel SPX12 may be output, and the pixel signal VOUT by the first to fourth sub-pixels SPX11 to SPX14 may be output. . That is, the first sub-pixel array 100_1f may simultaneously accumulate photo charges generated by the photodiode of the third sub-pixel SPX13 and the photodiode of the fourth sub-pixel SPX14 in one floating diffusion region. . Such a lead-out method may be a reset-signal-signal-signal-reset-signal-signal-signal (RSSSS) lead-out method. In this case, the third sub-pixel SPX13 and the fourth sub-pixel SPX14 are not used for the AF function, but the read-out speed of the entire first sub-pixel array 100_1f may be increased.

On the other hand, the first sub-pixel array 100_1f may perform an analog pixel binning operation in a low resolution mode. For example, the first sub-pixel array 100_1f transmits the pixel signal VOUT of the first, third, fifth, and seventh sub-pixels SPX11, SPX13, SPX15, and SPX17 to the first column output line CLO_0 ), and then, the pixel signal VOUT by the first to eighth subpixels SPX11 to SPX18 may be output to the first column output line CLO_0. Alternatively, for example, the pixel signal VOUT by the first, third, fifth and seventh sub-pixels SPX11, SPX13, SPX15, and SPX17 is output to the first column output line CLO_0, and reset again. The voltage is output as a pixel signal VOUT to the first column output line CLO_0, followed by a pixel signal VOUT by the second, fourth, sixth and eighth sub-pixels SPX12, SPX14, SPX16, and SPX18 May be output to the first column output line CLO_0.

On the other hand, the first sub-pixel array 100_1f may perform a digital pixel binning operation in a low resolution mode. For example, the first sub-pixel array 100_1f includes a pixel signal VOUT by the first and third sub-pixels SPX11 and SPX13, and a pixel signal by the fifth and seventh sub-pixels SPX15 and SPX17. (VOUT) can be output through different column output lines, and each pixel signal VOUT is generated by a CDS (e.g., 151 in FIG. 2) and an ADC (e.g., 153 in FIG. 2). It may be converted into a digital signal and stored in a buffer (eg, 155 of FIG. 2 ). The buffer 155 receives data corresponding to the pixel signals output from each of the first, third, fifth and seventh subpixels SPX11, SPX13, SPX15, and SPX17 as one signal, and a signal processing unit (e.g., FIG. 2 of 130) or to the outside of the image sensor. After that, the buffer 155 uses the data corresponding to the pixel signals output from each of the second, fourth, sixth, and eighth subpixels SPX12, SPX14, SPX16, and SPX18 as one signal, and the signal processing unit 130 or It can be output to the outside of the image sensor. Accordingly, an image sensor including the first sub-pixel array 100_1f may perform an AF function in units of pixels in a high resolution mode, and may perform an AF function in units of a pixel group in a low resolution mode. The array 100_1g may include first to fourth pixel groups PG1g to PG4g, and each of the first to fourth pixel groups PG1g to PG4g may include a plurality of pixels PX_X. Among the plurality of pixels PX_X, pixels PX_X disposed adjacent to each other in the second direction Y may form a shared pixel structure SHPX2Y sharing a floating diffusion region. That is, the shared pixel structure SHPX2Y may be a 4-Shared structure including four sub-pixels, and a shared pixel structure SHPX2Y that shares a floating diffusion region for every four sub-pixels may be formed. The operation of the first sub-pixel array 100_1g in each of the high-resolution mode and the low-resolution mode may be similarly applied to the operation of the first sub-pixel array 100_1f described above.

Referring to FIG. 6C, the first sub-pixel array 100_1h may include first to fourth pixel groups PG1h to PG4h, and each of the first to fourth pixel groups PG1h to PG4h is a plurality of pixels. They may include (PX_X). The pixels PX_X included in the same pixel group may form a shared pixel structure SHPX3 that shares a floating diffusion region. That is, the shared pixel structure SHPX3 may be an 8-Shared structure including 8 sub-pixels, and a shared pixel structure SHPX3 that shares a floating diffusion region for every 8 sub-pixels may be formed. Accordingly, subpixels included in different pixel groups may not share the floating diffusion region. The operation in the high resolution mode and the operation in the low resolution mode of the first sub-pixel array 100_1h will be described later with reference to FIGS. 9 to 11.

Referring to FIG. 6D, the first sub-pixel array 100_1i may include first to fourth pixel groups PG1i to PG4i, and each of the first to fourth pixel groups PG1i to PG4i is a plurality of pixels. They may include (PX_X). The pixels PX_X included in pixel groups that are adjacent to each other in the first direction X may form a shared pixel structure SHPX4X that shares a floating diffusion region. That is, the shared pixel structure SHPX4X may be a 16-Shared structure including 16 sub-pixels, and a shared pixel structure SHPX4X sharing a floating diffusion region for every 16 sub-pixels may be formed.

For example, the first sub-pixel SPX11 to the eighth sub-pixel SPX18 of the first pixel group PG1i and the first sub-pixel SPX21 to the eighth sub-pixel SPX28 of the second pixel group PG2i ) Forms one shared pixel structure (SHPX4X) that shares a floating diffusion region, and first subpixels SPX31 to 8th subpixels SPX38 and fourth pixel groups of the third pixel group PG3i ( The first to eighth subpixels SPX41 to SPX48 of the PG4i) may form one shared pixel structure SHPX4X that shares a floating diffusion region. Accordingly, subpixels included in different pixel groups may share the floating diffusion region.

The first sub-pixel array 100_1j may include first to fourth pixel groups PG1j to PG4j, and each of the first to fourth pixel groups PG1j to PG4j includes a plurality of pixels PX_X. can do. The pixels PX_Y included in pixel groups adjacent to each other in the second direction Y may form a shared pixel structure SHPX4Y that shares a floating diffusion region. That is, the shared pixel structure SHPX4Y may be a 16-Shared structure including 16 sub-pixels, and a shared pixel structure SHPX4Y sharing a floating diffusion region for every 16 sub-pixels may be formed.

For example, the first sub-pixel SPX11 to the eighth sub-pixel SPX18 of the first pixel group PG1j and the first sub-pixel SPX31 to the eighth sub-pixel SPX38 of the third pixel group PG3j ) Forms one shared pixel structure (SHPX4Y) that shares a floating diffusion region, and first subpixels SPX21 to 8th subpixels SPX28 and a fourth pixel group of the second pixel group PG2j ( The first to eighth sub-pixels SPX41 to SPX48 of PG4j) may form one shared pixel structure SHPX4Y that shares a floating diffusion region. Accordingly, subpixels included in different pixel groups may share the floating diffusion region.

The operation of the first sub-pixel array 100_1i and the first sub-pixel array 100_1j in the high-resolution mode and the operation in the low-resolution mode are performed in the high-resolution mode and the low-resolution mode of the first sub-pixel array 110_1h of FIG. 6C. A description of the operation in the mode may be similarly applied.

Referring to FIG. 6E, the first sub-pixel array 100_1k may include first to fourth pixel groups PG1k to PG4k, and each of the first to fourth pixel groups PG1k to PG4k is a plurality of pixels. They may include (PX_X). The pixels PX_X included in the first to fourth pixel groups PG1k to PG4k may form a shared pixel structure SHPX5 that shares a floating diffusion region. That is, the shared pixel structure SHPX5 may be a 32-Shared structure including 32 sub-pixels, and a shared pixel structure SHPX5 that shares a floating diffusion region for every 32 sub-pixels may be formed. The operation of the first sub-pixel array 100_1i and the first sub-pixel array 100_1j in the high-resolution mode and the operation in the low-resolution mode are performed in the high-resolution mode and the low-resolution mode of the first sub-pixel array 110_1h of FIG. 6C. A description of the operation in the mode may be similarly applied.

In FIGS. 6A to 6E, the shared pixel structures SHPX1 to SHPX5 formed in the first sub-pixel arrays 110_1e to 110_1k have been described, but the image sensor according to the present disclosure is not limited thereto. A structure in which subpixels included in the first subpixel arrays 110_1e to 110_1k share a floating diffusion node may be configured in various ways.

7 is an exemplary circuit diagram of subpixels sharing a floating diffusion region in an exemplary embodiment according to the present disclosure. 7 is a description of a shared pixel structure that provides a dual conversion gain (DCG) function. The shared pixel structure of FIG. 7 includes four photodiodes sharing a first floating diffusion region (HCG_FD_A), and a second floating Although it is illustrated as including four photodiodes sharing the diffusion region HCG_FD_B, the present disclosure is not limited thereto, and the shared pixel structure may be variously configured for convenience of description.

Referring to FIG. 7, the shared pixel structure SHPX' includes first to eighth photodiodes PD11 to PD18, first to eighth transfer transistors TX11 to TX18, first and second selection transistors SX1, SX2), first and second drive transistors SF1 and SF2, and first to fourth reset transistors RX11, RX21, RX12, and RX22.

Each of the first to fourth transfer transistors TX11 to TX14 connects each of the first to fourth photodiodes PD11 to PD14 to a first floating diode in response to the corresponding first to fourth transmission control signals TS11 to TS14. It can be connected to the fusion region (HCG_FD_A). Each of the 5th to 8th transfer transistors TX15 to TX18 connects each of the 5th to 8th photodiodes PD15 to PD18 to a second floating D in response to the corresponding fifth to eighth transmission control signals TS15 to TS18. It can be connected to the fusion region (HCG_FD_B). For example, subpixels including the first to fourth photodiodes PD11 to PD14 may share the first floating diffusion region HCG_FD_A, and may include the fifth to eighth photodiodes PD15 to PD18. The included subpixels may share the second floating diffusion region HCG_FD_B.

The first reset transistor RX11 and the second reset transistor RX21 are accumulated in the first floating diffusion region HCG_FD_A in response to the first reset control signal RS11 and the second reset control signal RS21, respectively. The charges can be reset periodically. The source electrode of the first reset transistor RX11 may be connected to the first floating diffusion region HCG_FD_A, and the drain electrode may be connected to the second reset transistor RX21 and the third floating diffusion region LCG_FD. The source electrode of the second reset transistor RX21 may be connected to the first reset transistor RX11 and the third floating diffusion region LCG_FD, and the drain electrode may be connected to the power voltage VPIX.

The third reset transistor RX12 and the fourth reset transistor RX22 are charged in the second floating diffusion region HCG_FD_B in response to the third reset control signal RS21 and the fourth reset control signal RS22, respectively. You can reset them periodically. The source electrode of the third reset transistor RX12 may be connected to the second floating diffusion region HCG_FD_B, and the drain electrode may be connected to the fourth reset transistor RX22 and the third floating diffusion region LCG_FD. The source electrode of the fourth reset transistor RX22 may be connected to the third reset transistor RX12 and the third floating diffusion region LCG_FD, and the drain electrode may be connected to the power voltage VPIX.

When the first reset transistor RX11 is turned on, the first floating diffusion region HCG_FD_A and the third floating diffusion region LCG_FD may be connected to each other. Also, when the third reset transistor RX12 is turned on, the second floating diffusion region HCG_FD_B and the third floating diffusion region LCG_FD may be connected to each other. Therefore, when all of the first reset transistors RX11 and RX21 are turned on, the first floating diffusion region HCG_FD_A, the second floating diffusion region HCG_FD_B, and the third floating diffusion region LCG_FD are Everything can be connected. Therefore, the shared pixel structure of the image sensor according to the present disclosure is in the shared pixel structure (SHPX2X, SHPX2Y) of the 4-Shared structure of FIG. 6B according to the first reset control signal (RG11) and the second reset control signal (RG12). It may be changed to a shared pixel structure (SHPX3) having an 8-Shared structure of FIG. 6C.

The first selection transistor SX and the second selection transistor SX2 are each in response to the corresponding first selection signal SSELS1 and the second selection signal SSELS2, respectively, through the column output line CDS (for example, FIG. The pixel signal VOUT may be output to 151 of 2.

In the image sensor, as the capacitance of the floating diffusion region decreases, the conversion efficiency may increase, and the conversion efficiency may decrease as the capacitance increases. On the other hand, as the capacitance of the floating diffusion region increases, the image sensor may accumulate a relatively large amount of photo charges in the floating diffusion region, so that the number of times the reset operation is performed may be reduced, thereby increasing the operation speed. Accordingly, the image sensor according to the present disclosure operates a pixel array in a 4-shared structure in a high conversion gain (HCG) mode and an 8-shared structure in a low conversion gain (LCG) mode as needed, thereby dual conversion (DCG). gain) function can be supported.

8 to 11 are timing diagrams for describing an operation of an image sensor according to an exemplary embodiment of the present disclosure. In the drawings, for convenience of description, the first sub-pixel array 100_1h including the shared pixel structure SHPX3 illustrated in FIG. 6C is used, but the image sensor of the present disclosure is not limited thereto. The image sensor according to an exemplary embodiment of the present disclosure can be variously modified.

In an exemplary embodiment of the operation of the image sensor described in FIGS. 8 and 9, in a high resolution mode, a plurality of pixels PX_X included in the first pixel array 100_1h all output a pixel signal for an AF function. This is an example. An exemplary embodiment of the operation of the image sensor described in FIG. 10 is an embodiment in which some of the pixels PX_X output a pixel signal for an AF function in a high resolution mode. An exemplary embodiment of the operation of the image sensor described in FIG. 11 is an embodiment in which a pixel signal for an AF function is output from a pixel group in a low resolution mode.

5, 6C, and 8, the first sub-pixel SPX11 is a first photodiode PD11 by a switching operation of the first transfer transistor TX11 controlled by the first transmission control signal TS11. ) May accumulate in the floating diffusion region FD1. In the second sub-pixel SPX12, photo charges generated in the second photodiode PD12 by the switching operation of the second transfer transistor TX12 controlled by the second transfer control signal TS12 are transferred to the floating diffusion region ( Can accumulate in FD1). In the seventh sub-pixel SPX17, photo charges generated by the seventh photodiode may be accumulated in the floating diffusion region FD1 by the switching operation of the seventh transfer transistor controlled by the seventh transfer control signal TS17. have. In the eighth sub-pixel SPX18, photo charges generated by the eighth photodiode may be accumulated in the floating diffusion region FD1 by the switching operation of the eighth transfer transistor controlled by the eighth transfer control signal TS18. have.

After the first pixel group PG1h is reset, the first to eighth transfer transistors of the first to eighth sub-pixels SPX11 to SPX18 may be sequentially turned on. That is, after the reset control signal RS1 changes from the logic high level to the logic low level, the first to eighth transmission control signals TS11 to TS18 may sequentially change from the logic low level to the logic high level.

In the period in which the reset control signal RS1 changes from the logic high level to the logic low level and then back to the logic high level, the ramp voltage RMP generated by the ramp signal generator (for example, 157 in FIG. 2) is 9 May contain pulses. Each pulse may have a shape of a triangular wave that sequentially decreases and then increases again at a time. In this drawing, although the lowest level of the pulse is shown to gradually decrease, the present disclosure is not limited thereto, and various modifications are possible.

The first pulse R may be a pulse corresponding to the pixel voltage VOUT when the floating diffusion region FD1 of the first pixel group PG1h is reset. The reset voltage may have a relatively small size of the changed signal.

The second pulse S1 may be a pulse corresponding to the pixel signal VOUT according to the photo charge generated by the first photodiode PD11 of the first subpixel SPX11. Since the voltage drop is further added to the reset voltage of the pixel signal VOUT, the second pulse S1 may be lower than the first pulse R and then recovered.

The third pulse S1S2 is a pixel signal VOUT according to photo charges generated from the first photodiode PD11 of the first subpixel SPX11 and the second photodiode PD12 of the second subpixel SPX12 It may be a pulse corresponding to. The fourth pulses S1 ... S7 may be pulses corresponding to the pixel signal VOUT according to the photo charges generated by the first to seventh photodiodes of the first to seventh subpixels SPX11 to PX17, The 5 pulses S1 ... S8 may be pulses corresponding to the pixel signal VOUT according to the photo charge generated by the first to eighth photodiodes of the first to eighth subpixels SPX11 to PX18.

As described above, the shape of the ramp voltage RMP may be due to the shape of the pixel signal VOUT output from the first pixel group PG1h. That is, the first pixel group PG1h first outputs the reset voltage as the pixel signal VOUT, and then outputs the pixel signal VOUT by the first sub-pixel SPX11, and then the first sub-pixel SPX11 and A pixel signal VOUT from the second subpixel SPX12 is output, a pixel signal VOUT from the first subpixel SPX11 to the third subpixel SPX13 is output, and the first subpixel SPX11 ) To the fourth sub-pixel (SPX14) outputs the pixel signal (VOUT), the first sub-pixel (SPX11) to the fifth sub-pixel (SPX15) of the pixel signal (VOUT), and the first sub-pixel A pixel signal VOUT by the (SPX11) to sixth sub-pixels SPX16 is output, a pixel signal VOUT by the first sub-pixel SPX11 to the seventh sub-pixel SPX17 is output, and a first The pixel signal VOUT by the sub-pixel SPX11 to the eighth sub-pixel SPX18 may be output. Such a lead-out method may be a reset-signal-signal-signal-signal-signal-signal-signal-signal (RSSSSSSS) lead-out method.

Photo charges generated in each of the first to eighth subpixels SPX11 to SPX18 included in the first pixel group PG1h may be sequentially accumulated in the floating diffusion region FD1, and a pixel signal VOUT ) Can be sequentially output. After the reset operation for the first pixel group PG1h is performed once, the pixel signal VOUT corresponding to the amount of photocharge generated in each of the first to eighth subpixels SPX11 to SPX18 is sequentially output. The image sensor according to the start is capable of high-speed operation. Therefore, when a high-speed operation is required, such as in the video mode, the number of reset operations is reduced and photocharges generated in each of the first to eighth sub-pixels SPX11 to SPX18 are sequentially accumulated in the floating diffusion region FD1. I can make it.

In addition, the first to eighth transfer transistors of the first to eighth sub-pixels SPX11 to SPX18 are sequentially turned on, corresponding to the amount of photocharge generated in each of the first to eighth sub-pixels SPX11 to SPX18. Since the pixel signals VOUT are sequentially output, a high-resolution mode for performing an AF function in units of pixels can be provided. In this case, all of the plurality of pixels PX_X included in the first pixel group PG1h may each output a pixel signal VOUT including AF information.

5, 6C, and 9, first to eighth transfer transistors of the first to eighth subpixels SPX11 to SPX18 may be sequentially turned on. That is, the first to eighth transmission control signals TS11 to TS18 may sequentially change from a logic low level to a logic high level.

The first pulse R1 of the ramp voltage RMP may be a pulse corresponding to the pixel voltage VOUT when the floating diffusion region FD1 of the first pixel group PG1h is reset. The second pulse S1 may be a pulse corresponding to the pixel signal VOUT according to the photo charge generated by the first photodiode PD11 of the first subpixel SPX11. The third pulse S1S2 is a pixel signal VOUT according to photo charges generated from the first photodiode PD11 of the first subpixel SPX11 and the second photodiode PD12 of the second subpixel SPX12 It may be a pulse corresponding to.

The fourth pulse R4 may be a pulse corresponding to the pixel voltage VOUT when the floating diffusion region FD1 of the first pixel group PG1h is reset. The fifth pulse S7 may be a pulse corresponding to the pixel signal VOUT according to photo charges generated by the seventh photodiode of the seventh sub-pixel SPX17. The sixth pulse S7S8 may be a pulse corresponding to the pixel signal VOUT according to photo charges generated from the seventh photodiode of the seventh subpixel SPX17 and the eighth photodiode of the eighth subpixel SPX18. have.

The first pixel group PG1h first outputs a reset voltage as the pixel signal VOUT, then outputs the pixel signal VOUT by the first subpixel SPX11, and then outputs the first subpixel SPX11 and the second The pixel signal VOUT by the sub-pixel SPX12 may be output. Thereafter, the first pixel group PG1h outputs a reset voltage as a pixel signal VOUT, and then outputs a pixel signal VOUT by the third subpixel SPX13, and the third subpixel SPX13 and the third subpixel SPX13 The pixel signal VOUT by the 4 sub-pixels SPX14 may be output. Thereafter, the first pixel group PG1h outputs the reset voltage as the pixel signal VOUT, and then outputs the pixel signal VOUT by the fifth sub-pixel SPX135, and the fifth sub-pixel SPX15 and The pixel signal VOUT by the 6 sub-pixels SPX16 may be output. Thereafter, the first pixel group PG1h outputs a reset voltage as a pixel signal VOUT, and then outputs a pixel signal VOUT by the seventh subpixel SPX17, and the seventh subpixel SPX17 and the The pixel signal VOUT by the 8 sub-pixels SPX18 may be output. Such a read-out method may be the RSSRSSRSSRSS readout method described above in the description of FIG. 6B.

Photo charges generated in some of the first to eighth sub-pixels SPX11 to SPX18 included in the first pixel group PG1h are accumulated in the floating diffusion region FD1, reset, and then again. Since photo charges generated by some of the other sub-pixels are accumulated in the floating diffusion region FD1, the image sensor can provide the AF function even when the capacitance of the floating diffusion region FD1 is small. In addition, the first to eighth transfer transistors of the first to eighth sub-pixels SPX11 to SPX18 are sequentially turned on, corresponding to the amount of photocharge generated in each of the first to eighth sub-pixels SPX11 to SPX18. Since the pixel signals VOUT are sequentially output, a high-resolution mode for performing an AF function in units of pixels can be provided. In this case, all of the plurality of pixels PX_X included in the first pixel group PG1h may each output a pixel signal VOUT including AF information.

The image sensor according to the present disclosure is not limited to the above-described read-out method. In outputting the pixel signal VOUT by each of the first to eighth subpixels SPX11 to SPX18, the photocharge generated by each of the photodiodes of the four subpixels is a floating diffusion region FD1. A read-out method in which a pixel signal VOUT is output while sequentially accumulating in the pixel signal VOUT and then a reset operation is repeated, that is, an RSSSSRSSSS readout method is also possible. Alternatively, a read-out method in which a pixel signal VOUT by one sub-pixel is output and then a reset operation is repeated, that is, a RSRSRSRSRSRSRSRS readout method is also possible.

5, 6C, and 10, the first transfer transistor TX11 of the first subpixel SPX11 and the second transfer transistor TX12 of the second subpixel SPX12 are simultaneously turned on, The third to eighth transfer transistors of the third to eighth sub-pixels SPX13 to SPX18 may be sequentially turned on. That is, the first transmission control signal TS11 and the second transmission control signal TS12 may simultaneously change from a logic low level to a logic high level, and the third to eighth transmission control signals TS13 to TS18 are sequentially It can change from a low level to a logic high level.

The first pulse R of the ramp voltage RMP may be a pulse corresponding to the pixel voltage VOUT when the floating diffusion region FD1 of the first pixel group PG1h is reset. The second pulse S1S2 is a pixel signal VOUT according to photo charges generated from the first photodiode PD11 of the first subpixel SPX11 and the second photodiode PD12 of the second subpixel SPX12 It may be a pulse corresponding to. The third pulses S1 ... S7 may be pulses corresponding to the pixel signal VOUT according to the photocharge generated by the first to seventh photodiodes of the first to seventh subpixels SPX11 to SPX17, The four pulses S1 to S8 may be pulses corresponding to the pixel signal VOUT according to the photo charges generated by the first to eighth photodiodes of the first to eighth subpixels SPX11 to SPX18.

That is, the first pixel group PG1h first outputs the reset voltage as the pixel signal VOUT, and then outputs the pixel signal VOUT by the first sub-pixel SPX11 and the second sub-pixel SPX12, Outputs a pixel signal VOUT from the first subpixel SPX11 to the third subpixel SPX13, and outputs a pixel signal VOUT from the first subpixel SPX11 to the fourth subpixel SPX14 And, the pixel signal VOUT by the first sub-pixel SPX11 to the fifth sub-pixel SPX15 is output, and the pixel signal VOUT by the first sub-pixel SPX11 to the sixth sub-pixel SPX16 Is output, the pixel signal VOUT by the first subpixel SPX11 to the seventh subpixel SPX17 is output, and the pixel signal by the first subpixel SPX11 to the eighth subpixel SPX18 ( VOUT) can be output. Such a lead-out method may be a reset-signal-signal-signal-signal-signal-signal-signal (RSSSSSS) lead-out method.

The image sensor according to the present disclosure may not use some of the plurality of pixels PX_X included in the first pixel group PG1h for the AF function. For example, the first sub-pixel SPX11 and the second sub-pixel SPX12 simultaneously accumulate photo charges in the floating diffusion region FD1, so that they may not be used for the AF function, and the third to eighth sub-pixels The pixels SPX3 to SPX8 can be used for the AF function.

In FIG. 10, a case in which only the first sub-pixel SPX11 and the second sub-pixel SPX12 are not used for the AF function has been described, but the present disclosure is not limited thereto. After the first sub-pixel SPX11 and the second sub-pixel SPX12 simultaneously accumulate photo charges in the floating diffusion region FD1, the third sub-pixel SPX13 and the fourth sub-pixel SPX14 are simultaneously By accumulating photo charges in the floating diffusion region FD1, the first to fourth sub-pixels SPX11 to SPX14 may not be used for the AF function. Such a lead-out method may be a reset-signal-signal-signal-signal-signal-signal (RSSSSS) lead-out method. In this case, the fourth to eighth sub-pixels SPX4 to SPX8 may be used for the AF function by sequentially accumulating photo charges in the floating diffusion region FD1.

Alternatively, the first sub-pixel SPX11 and the second sub-pixel SPX12 simultaneously accumulate photo charges in the floating diffusion region FD1, and then the third sub-pixel SPX13 and the fourth sub-pixel SPX14 At the same time, photo charges are accumulated in the floating diffusion region FD1, and then the fifth sub-pixel SPX15 and the sixth sub-pixel SPX16 simultaneously accumulate photo charges in the floating diffusion region FD1. The sixth sub-pixels SPX11 to SPX16 may not be used for the AF function. Such a lead-out method may be a reset-signal-signal-signal-signal-signal (RSSSS) lead-out method. At this time, the seventh sub-pixel SPX7 and the eighth sub-pixel SPX8 may be used for the AF function by sequentially accumulating photo charges in the floating diffusion region FD1.

The image sensor according to the present disclosure controls the subpixels included in the same pixel among the first to eighth subpixels SP1 to SPX8 to simultaneously accumulate photo charges in the floating diffusion region FD1, thereby enabling high-speed operation. It is possible. However, the image sensor according to the present disclosure is not limited to the above-described read-out method. It is also possible to accumulate photo charges generated by each of the photodiodes of the four sub-pixels in the floating diffusion region FD1 and repeat the reset operation. For example, a read-out method in which two transfer transistors included in one pixel are first turned on at the same time and then the remaining transfer transistors are sequentially turned on two times (RSSSRSSS read-out method) This is possible. The read-out method of the image sensor according to the present disclosure may be configured in various ways.

5, 6C, and 11, the transfer transistors of the sub-pixels having the same phase may be turned on at the same time. For example, the first, third, fifth and seventh transfer transistors of the first, third, fifth, and seventh subpixels SPX11, SPX13, SPX15, and SPX17 are turned on at the same time, and then The second, fourth, sixth and eighth transfer transistors of the second, fourth, sixth, and eighth sub-pixels SPX12, SPX14, SPX16, and SPX18 may be turned on at the same time. That is, the first, third, fifth and seventh transmission control signals TS11, TS13, TS15, and TS17 may simultaneously change from a logic low level to a logic high level, and thereafter, the second, fourth, sixth and The eighth transmission control signals TS12, TS14, TS16, and TS18 may simultaneously change from a logic low level to a logic high level.

The first pulse R of the ramp voltage RMP may be a pulse corresponding to the pixel voltage VOUT when the floating diffusion region FD1 of the first pixel group PG1h is reset. The second pulse S1S3S5S7 depends on the photo charges generated by the first, third, fifth and seventh photodiodes of the first, third, fifth and seventh sub-pixels SPX11, SPX13, SPX15, SPX17. It may be a pulse corresponding to the pixel signal VOUT. The third pulses S1 to S8 may be pulses corresponding to a pixel signal VOUT according to photo charges generated by the first to eighth photodiodes of the first to eighth subpixels SPX11 to SPX18. That is, the first pixel group PG1h first outputs the reset voltage as the pixel signal VOUT, and then the pixel signal from the first, third, fifth and seventh sub-pixels SPX11, SPX13, SPX15, and SPX17. The (VOUT) may be output and a pixel signal VOUT by the first to eighth subpixels SPX11 to SPX18 may be output. Such a lead-out method may be a reset-signal-signal (RSS) lead-out method.

The image sensor according to the present disclosure may perform an AF function in units of pixel groups in a low resolution mode. That is, the pixel signal VOUT according to the photo charge generated by the first, third, fifth, and seventh photodiodes and the pixel signal according to the photo charge generated by the second, fourth, sixth and eighth photodiodes By comparing (VOUT) with each other, the AF function can be performed. In a low-illuminance situation, since the amount of photocharge generated by one photodiode decreases, the image sensor may perform an AF function by accumulating all photocharges generated by a plurality of photodiodes.

However, the image sensor according to the present disclosure is not limited to the embodiment illustrated in FIG. 11. For example, the first pixel group PG1h outputs the pixel signal VOUT by the first, third, fifth, and seventh sub-pixels SPX11, SPX13, SPX15, and SPX17, is reset, and then The pixel signal VOUT by the second, fourth, sixth, and eighth sub-pixels SPX12, SPX14, SPX16, and SPX18 may be output. (Reset-signal-reset-signal (RSRS) read-out method) Or, the first pixel group PG1h first outputs a reset voltage as a pixel signal VOUT, and then the first and fifth sub-pixels SPX11, SPX15 ) Outputs the pixel signal VOUT, is reset, outputs the pixel signal VOUT by the second and sixth sub-pixels SPX12 and SPX16, is reset, and then the third and seventh sub-pixels The pixel signal VOUT by the (SPX13, SPX17) may be output, and after reset, the pixel signal VOUT by the fourth and eighth sub-pixels SPX14 and SPX18 may be output. (RSRSRSRS (reset-signal-reset-signal-reset-signal-reset-signal) readout method) Or, the first pixel group PG1h first outputs the reset voltage as a pixel signal VOUT, and then the first and The pixel signal VOUT is output by the fifth sub-pixels SPX11 and SPX15, and the pixel signal VOUT by the first, second, fifth and sixth sub-pixels SPX11, SPX12, SPX15, SPX16 is And outputs the pixel signal VOUT by the third and seventh sub-pixels SPX13 and SPX17 after being reset, and the third, fourth, seventh and eighth sub-pixels SPX13, SPX14, SPX17, The pixel signal VOUT by SPX18) may also be output. (Reset-signal-signal-reset-signal-signal (RSSRSS) read-out method) The image sensor according to the present disclosure is not limited to operating according to the above-described operation method. Various combinations of the above-described operation methods can be applied.

12 is a diagram illustrating a pixel array of an image sensor according to an exemplary embodiment of the present disclosure, and is a diagram illustrating an exemplary embodiment of a first sub-pixel array included in the pixel array. For the same reference numerals as in FIG. 3A, overlapping descriptions in FIG. 13 will be omitted.

Referring to FIG. 12, a first sub-pixel array 100_1d includes a plurality of pixels arranged along a row direction (eg, a first direction (X)) and a column direction (eg, a second direction (Y)). It may include pixels PX_X. Each of the plurality of pixels PX_X may include one micro lens ML.

In an exemplary embodiment, each of the first to fourth pixel groups PG1d to PG4d may include nine pixels PX_X, and one pixel PX_X is disposed adjacent to the first direction X. It may include two sub-pixels. For example, each of the first to fourth pixel groups PG1d to PG4d may include 18 subpixels arranged in 3 rows and 6 columns. For example, the first pixel group PG1d may include first to eighteenth subpixels SPX11 to SPX118, and the second pixel group PG2d is the first to eighteenth subpixels SPX21 to SPX218. May include, and the third pixel group PG3d may include first to 18th subpixels SPX31 to SPX318, and the fourth pixel group PG4d may include the first to 18th subpixels SPX41 to SPX4d8) may be included.

The first sub-pixel array 110_1d may include a color filter so that the plurality of pixels PX_X can sense various colors. In an exemplary embodiment, the color filter may include filters that sense red (R), green (G), and blue (B), and each of the first to fourth pixel groups PG1d to PG4d is the same color filter. It may include pixels PX_X including. However, the present disclosure is not limited thereto, and filters for sensing yellow or white may be included. In an exemplary embodiment, each of the first to fourth pixel groups PG1d to PG4d may include a color filter to correspond to the Bayer pattern. However, this is only an example, and one pixel group may include different color filters therein.

In an exemplary embodiment, the first subpixel array 110_1d may form a shared pixel structure in which subpixels included in each of the plurality of pixels PX_X share a floating diffusion region with each other. For example, nine floating diffusion regions may be formed in one pixel group.

In an exemplary embodiment, a shared pixel structure may be formed in which pixels PX_X disposed in the same row within one pixel group share one floating diffusion region. Alternatively, a shared pixel structure may be formed in which pixels PX_X arranged in the same column within one pixel group share one floating diffusion region. For example, three floating diffusion regions may be formed in one pixel group.

In an exemplary embodiment, pixels PX_X included in one pixel group may share a floating diffusion region with each other. For example, pixels PX_X included in different pixel groups may include different floating diffusion regions. Alternatively, for example, pixels PX_X included in pixel groups adjacent to each other in the row direction (eg, the first direction X) may share a floating diffusion region with each other. Alternatively, for example, pixels PX_X included in pixel groups adjacent to each other in the column direction (eg, the second direction Y) may share a floating diffusion region with each other. Alternatively, for example, the pixels PX_X included in the first to fourth pixel groups PG1d to PG4d may share a floating diffusion region with each other.

In an exemplary embodiment, an image sensor including the first sub-pixel array 110_1d may perform an AF function in pixel units in a first mode, that is, a high resolution mode, and a pixel in a second mode, that is, a low resolution mode. You can also perform the AF function in groups. The resolution in the low resolution mode of the image sensor may be less than or equal to 1/9 times the resolution in the high resolution mode.

Alternatively, the image sensor according to the present disclosure may perform an AF function in units of a plurality of pixels PX_X included in one pixel group and disposed in the same row in a third mode, that is, a medium resolution mode. For example, a pixel signal corresponding to the amount of photocharge generated by each photodiode of the first, third, and fifth subpixels SPX11, SPX13, and SPX15 of the first pixel group PG1, and a first pixel group The AF function may be performed by processing a pixel signal corresponding to the amount of photocharge generated by each photodiode of the second, fourth, and sixth subpixels SPX12, SPX14, and SPX16 of the PG1. In an exemplary embodiment, the resolution in the medium resolution mode may be greater than 1/9 times the resolution in the high resolution mode and less than or equal to 1/3 times the resolution in the high resolution mode.

The present disclosure is not limited thereto, and each of the first to fourth pixel groups PG1d to PG4d may include 16 pixels PX_X, or may include 32 subpixels arranged in 4 rows and 8 columns. have. Alternatively, in an exemplary embodiment, each of the first to fourth pixel groups PG1d to PG4d is a pixel including two subpixels disposed adjacent to each other in the second direction Y (eg, PX_Y in FIG. 3 ). It may also include. In the image sensor according to the present disclosure, the number of sub-pixels included in one pixel group and the arrangement of the sub-pixels may be variously configured.

Claims (10)

A pixel array including a plurality of first pixel groups including a plurality of pixels disposed in a first direction and a second direction; And
A row driver that provides control signals to the pixel array based on each of a high resolution mode and a low resolution mode,
Each of the plurality of pixels includes a first sub-pixel including a first photodiode, a second sub-pixel including a second photodiode, and one micro lens,
The first sub-pixel and the second sub-pixel are disposed adjacent to each other in a first direction and share a floating diffusion region,
The row driver, in the high resolution mode, provides the control signals to perform an auto focus (AF) function in units of the pixels, in the low resolution mode, provides the control signals to perform an AF function in units of a pixel group,
The image sensor, characterized in that the resolution in the low resolution mode is less than or equal to 1/4 of the resolution in the high resolution mode. The method of claim 1,
The row driver in the high-resolution operation mode,
Providing the control signals so that all of the plurality of pixels included in the plurality of first pixel groups perform an AF function,
And providing the control signals such that photo charges generated in the first sub-pixel and the second sub-pixel are all accumulated in the floating diffusion region and then reset. The method of claim 1,
The row driver in the high-resolution operation mode,
Providing the control signals so that all of the plurality of pixels included in the plurality of first pixel groups perform an AF function,
Providing the control signals such that the photo charge generated in the first sub-pixel is accumulated in the floating diffusion region and then reset, and the photo charge generated in the second sub-pixel is accumulated in the floating diffusion region again. An image sensor characterized by. The method of claim 1,
The row driver in the high-resolution operation mode,
Providing the control signals so that some of the plurality of pixels perform an AF function,
And providing control signals so that the first sub-pixel and the second sub-pixel included in some other pixels of the plurality of pixels simultaneously accumulate photo charges in the floating diffusion region. The method of claim 1,
At least two of the plurality of pixels share the floating diffusion region with each other,
Wherein the row driver provides the control signals so that the first sub-pixels included in each of the two pixels simultaneously accumulate photo charges in the floating diffusion region in the low resolution operation mode. The method of claim 1,
A first pixel and a second pixel disposed adjacent among the plurality of pixels share a floating diffusion region with each other,
In response to a control signal provided by the row driver, a first floating diffusion region of the first pixel and a second floating diffusion region of the second pixel are electrically connected to each other, thereby sharing a floating diffusion region with each other. An image sensor, characterized in that. A pixel array including a plurality of pixel groups including a plurality of pixels arranged in a row direction and a column direction; And
Including a row driver for providing control signals to the pixel array based on an operation mode including first to third modes,
Each of the plurality of pixels includes a first sub-pixel including a first photodiode, a second sub-pixel including a second photodiode, and one micro lens,
The first sub-pixel and the second sub-pixel are disposed adjacent to each other and share a floating diffusion region,
The row driver, in the first mode, provides the control signals to perform the AF function in units of the pixels, in the second mode, provides the control signals to perform the AF function in units of pixel groups, and the third In the mode, the control signals are provided to perform the AF function in units of pixels arranged in the same row in one pixel group. The method of claim 7,
A plurality of pixels included in the same pixel group among the plurality of pixel groups share a floating diffusion region,
The row driver provides control signals so that the first sub-pixel and the second sub-pixel included in some of the plurality of pixels included in the same pixel group simultaneously accumulate photo charges in the floating diffusion region. An image sensor, characterized in that. The method of claim 7,
A plurality of pixels included in the same pixel group among the plurality of pixel groups share a floating diffusion region,
In the second mode, the row driver provides control signals so that first subpixels included in the plurality of pixels included in the same pixel group simultaneously accumulate photo charges in the floating diffusion region, and the plurality of And providing control signals so that second sub-pixels included in pixels simultaneously accumulate photo charges in the floating diffusion region. The method of claim 7,
And two adjacent pixel groups of the plurality of pixel groups share a floating diffusion region.

Images