IMAGE SENSOR AND ELECTRONIC DEVICE HAVING THE SAME

• US 20170142325A1
• Filed: 11/16/2016
• Published: 05/18/2017
• Est. Priority Date: 11/16/2015
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd. (Samsung Group)
• Original Assignee: Samsung Electronics Co. Ltd. (Samsung Group)
• Inventors: Lee, Sangmin, Shimokawa, Shuichi
• Granted Patent: US 10,379,317 B2
• Time in Patent Office: Days
• CPC Class Codes: G02B 7/28 Systems for automatic generation of focusing signals
• CPC Class Codes: H01L 27/14603 Special geometry or disposition of pixel-elements, address-lines or gate-electrodes
• CPC Class Codes: H01L 27/14612 involving a transistor
• CPC Class Codes: H01L 27/14641 Electronic components shared by two or more pixel-elements, e.g. one amplifier shared by two pixel elements
• CPC Class Codes: H04N 23/672 based on the phase difference signals
• CPC Class Codes: H04N 25/46 by combining or binning pixels
• CPC Class Codes: H04N 25/704 Pixels specially adapted for focusing, e.g. phase difference pixel sets
• CPC Class Codes: H04N 25/778 comprising amplifiers shared between a plurality of pixels, i.e. at least one part of the amplifier must be on the sensor array itself

Abstract

An image sensor according to an embodiment may include a plurality of pixels. Each pixel of the plurality of pixels may include first, second, third and fourth photodiodes configured to convert light into an electric signal, and an electric circuit configured to add at least two of the electrical signals converted respectively by the first, second, third and fourth photodiodes and then output the added signals. An electronic device according to an embodiment may include the image sensor. The image sensor and the electronic device may offer an auto focusing function by controlling signals converted by and outputted from the plurality of photodiodes. Other various embodiments are possible.

Claims

1. An image sensor including a plurality of pixels, each of the plurality of pixels comprising:

first, second, third and fourth photodiodes each configured to convert light into an electric signal, respectively; and

an electric circuit configured to;

add at least two of the electrical signals converted respectively by the first, second, third and fourth photodiodes to generate added signals, and

output the added signals.

2. The image sensor of claim 1, wherein the first, second, third and fourth photodiodes are disposed respectively at upper left, upper right, lower left and lower right positions of the image sensor and are arranged in a grid form.

3. The image sensor of claim 1, wherein the electric circuit further includes:

a plurality of floating diffusion regions configured to;

add the at least two of the electrical signals converted respectively by the first, second, third and fourth photodiodes to generate at least two added signals, and

output the at least two added signals; and

a plurality of transfer gates configured to selectively electrically connect the photodiodes and the plurality of floating diffusion regions.

4. The image sensor of claim 3, wherein the plurality of floating diffusion regions further include:

a first floating diffusion region configured to;

add the electric signals received from the first or third photodiode to generate a first added signal; and

output the first added signal; and

a second floating diffusion region configured to;

add the electric signals received from the second or fourth photodiode to generate a second added signal; and

output the second added signal, wherein the plurality of transfer gates includes;

a first transfer gate configured to selectively electrically connect the first photodiode and the first floating diffusion region;

a second transfer gate configured to selectively electrically connect the second photodiode and the second floating diffusion region;

a third transfer gate configured to selectively electrically connect the third photodiode and the first floating diffusion region;

a fourth transfer gate configured to selectively electrically connect the fourth photodiode and the second float diffusion region;

a fifth transfer gate configured to selectively electrically connect the first and second photodiodes; and

a sixth transfer gate configured to selectively electrically connect the third and fourth photodiodes.

5. The image sensor of claim 4, wherein the first and fourth transfer gates are electrically connected so as to be controlled by a same first control signal, wherein the second and third transfer gates are electrically connected so as to be controlled by a same second control signal, and wherein the fifth and sixth transfer gates are electrically connected so as to be controlled by a same third control signal.

6. The image sensor of claim 3, wherein the plurality of floating diffusion regions includes:

a first floating diffusion region configured to;

add the electric signals received from the first photodiode to generate a first added signal; and

output the first added signal; and

a second floating diffusion region configured to;

add the electric signals received from the fourth photodiode to generate a second added signal; and

output the second added signal,

wherein the plurality of transfer gates includes;

a first transfer gate configured to selectively electrically connect the first and second photodiodes;

a second transfer gate configured to selectively electrically connect the third and fourth photodiodes;

a third transfer gate configured to selectively electrically connect the first and third photodiodes; and

a fourth transfer gate configured to selectively electrically connect the second and fourth photodiodes.

7. The image sensor of claim 6, wherein the first and second transfer gates are electrically connected so as to be controlled by a same first control signal, and wherein the third and fourth transfer gates are electrically connected so as to be controlled by a same second control signal.

8. An electronic device comprising:

an image sensor including a plurality of pixels; and

a processor configured to control operations of the image sensor and perform an auto focusing function,

wherein each of the plurality of pixels comprises;

first, second, third and fourth photodiodes configured to convert light into an electric signal, respectively; and

an electric circuit configured to;

add at least two of the electrical signals converted respectively by the first, second, third and fourth photodiodes to generate added signals, and

output the added signals.

9. The electronic device of claim 8, wherein the first, second, third and fourth photodiodes are disposed respectively at upper left, upper right, lower left and lower right positions of the image sensor and are arranged in a grid form.

10. The electronic device of claim 9, wherein the electric circuit further includes:

a plurality of floating diffusion regions configured to;

add the at least two of the electrical signals converted respectively by the first, second, third and fourth photodiodes to generate at least two added signals, and

output the at least two added signals; and

a plurality of transfer gates configured to selectively electrically connect the photodiodes and the plurality of floating diffusion regions,

wherein the processor outputs at least one control signal for controlling the plurality of transfer gates.

11. The electronic device of claim 10, wherein the plurality of floating diffusion regions includes:

a first floating diffusion region configured to;

add the electric signals received from the first or third photodiode to generate a first added signal; and

output the first added signal; and

a second floating diffusion region configured to;

add the electric signals received from the second or fourth photodiode to generate a second added signal; and

output the second added signal,

wherein the plurality of transfer gates includes;

a first transfer gate configured to selectively electrically connect the first photodiode and the first floating diffusion region;

a second transfer gate configured to selectively electrically connect the second photodiode and the second floating diffusion region;

a third transfer gate configured to selectively electrically connect the third photodiode and the first floating diffusion region;

a fourth transfer gate configured to selectively electrically connect the fourth photodiode and the second floating diffusion region;

a fifth transfer gate configured to selectively electrically connect the first and second photodiodes; and

a sixth transfer gate configured to selectively electrically connect the third and fourth photodiodes.

12. The electronic device of claim 11, wherein the first and fourth transfer gates are electrically connected so as to be controlled by a same first control signal, wherein the second and third transfer gates are electrically connected so as to be controlled by a same second control signal, and wherein the fifth and sixth transfer gates are electrically connected so as to be controlled by a same third control signal.

13. The electronic device of claim 10, wherein the plurality of floating diffusion regions includes:

a first floating diffusion region configured to;

add the electric signals received from the first photodiode to generate a first added signal; and

output the first added signal; and

a second floating diffusion region configured to;

add the electric signals received from the fourth photodiode to generate a second added signal; and

output the second added signal, and

wherein the plurality of transfer gates includes;

a first transfer gate configured to selectively electrically connect the first and second photodiodes;

a second transfer gate configured to selectively electrically connect the third and fourth photodiodes;

a third transfer gate configured to selectively electrically connect the first and third photodiodes; and

a fourth transfer gate configured to selectively electrically connect the second and fourth photodiodes.

14. The electronic device of claim 13, wherein the first and second transfer gates are electrically connected so as to be controlled by a same first control signal, and wherein the third and fourth transfer gates are electrically connected so as to be controlled by a same second control signal.

15. A method of sensing images, comprising:

converting light into first, second, third, and fourth electric signals by first, second, third, and fourth photodiodes;

adding at least two of the first, second, third, and fourth electric signals to generate added signals; and

outputting the added signals.

16. The method of claim 15, further comprising:

selectively electrically connecting the photodiodes and a plurality of floating diffusion regions, wherein the adding and the outputting is performed by the plurality of floating diffusion regions.

17. The method of claim 16, wherein the selectively electrically connecting is performed with a plurality of transfer gates.

18. The method of claim 17, further comprising:

controlling first and second transfer gates of the plurality of transfer gates with a same first control signal; and

controlling third and fourth transfer gates of the plurality of transfer gates with a same second control signal.

19. The method of claim 17, further comprising:

controlling first and fourth transfer gates of the plurality of transfer gates with a same first control signal;

controlling second and third transfer gates of the plurality of transfer gates with a same second control signal; and

controlling fifth and sixth transfer gates of the plurality of transfer gates with a same third control signal.

20. The method of claim 15, further comprising:

comparing the added signals to detect a phase difference between the added signals; and

processing the detected phase difference to perform an auto focus function.