Imaging systems with high dynamic range and phase detection pixels

Patent metadata

Field	Value
Publication number	US-10015416-B2
Application number	US-201615162914-A
Country	US
Kind code	B2
Filing date	May 24, 2016
Priority date	May 24, 2016
Publication date	Jul 3, 2018
Grant date	Jul 3, 2018

Abstract

An image sensor may have a pixel array, and the pixel array may include a plurality of image pixels that gather image data and a plurality of phase detection pixels that gather phase information. The phase detection pixels may be arranged in phase detection pixel blocks, and each phase detection pixel group may include edge pixels. The edge pixels of each phase detection pixel group may be covered by microlenses that also cover a portion of a center pixel. The pixel array may also include high dynamic range pixel blocks. Each high dynamic range pixel block may include pixels within the phase detection pixel block and other pixels (e.g., corner pixels). A subset of the plurality of image pixels in the pixel array may be arranged in pixel blocks. Each pixel block may include a phase detection pixel block and a high dynamic range pixel block.

First claim

What is claimed is:

1. An image sensor having a pixel array, wherein the pixel array comprises:
a plurality of pixels that gather image data and that each have respective and uniformly sized light collecting areas;
a phase detection pixel block that gathers phase information, wherein the phase detection pixel block comprises a first pixel of the plurality of pixels and wherein the first pixel is covered by a first microlens; and
a high dynamic range pixel block that comprises:
the first pixel of the plurality of pixels, wherein the first pixel receives a first amount of light over a first time period;
a second pixel of the plurality of pixels, wherein the second pixel receives a second amount of light over the first time period, wherein the first amount of light is greater than the second amount of light; and
a third pixel of the plurality of pixels, wherein the third pixel receives a third amount of light over the first time period, wherein the second amount of light is greater than the third amount of light, and wherein the first microlens that covers the first pixel also covers at least a portion of the third pixel.

2. The image sensor of claim 1 , wherein the high dynamic range pixel block further comprises:
a fourth pixel of the plurality of pixels, wherein the phase detection pixel block further comprises the fourth pixel.

3. The image sensor of claim 2 , wherein the fourth pixel is covered by a second microlens and wherein the second microlens covers the fourth pixel and covers at least a portion of the third pixel.

4. The image sensor of claim 3 , wherein the second pixel is covered by a third microlens, wherein the first microlens covers a first area of the plurality of pixels, wherein the third microlens covers a second area of the plurality of pixels, and wherein the first area is larger than the second area.

5. The image sensor of claim 4 , wherein the high dynamic range pixel block further comprises:
a plurality of color filters that each cover a pixel, wherein the plurality of color filters are formed over the high dynamic range pixel block.

6. The image sensor of claim 5 , wherein each of the plurality of color filters has the same color.

7. The image sensor of claim 2 , wherein the fourth pixel is covered by the first microlens.

8. The image sensor of claim 7 , wherein the first microlens has an opening and wherein the opening is above the third pixel.

9. The image sensor of claim 2 , wherein the high dynamic range pixel block further comprises:
a fifth pixel of the plurality of pixels, wherein the phase detection pixel block further comprises the fifth pixel; and
a sixth pixel of the plurality of pixels, wherein the phase detection pixel block further comprises the sixth pixel.

10. The image sensor of claim 9 , wherein the fifth pixel is covered by a fourth microlens and wherein the fourth microlens covers at least a portion of the third pixel.

11. The image sensor of claim 10 , wherein the fourth microlens covers at least a portion of the sixth pixel.

12. An image sensor having a pixel array, wherein the pixel array comprises:
a pixel block that has a microlens configuration formed over the pixel block, wherein the pixel block comprises:
a plurality of edge pixels that are exposed to a first amount of light during a first time period;
a plurality of corner pixels that are exposed to a second amount of light during the first time period, wherein the second amount of light is less than the first amount of light and wherein each pixel of the plurality of corner pixels is covered by a single microlens; and
a center pixel that is exposed to a third amount of light during the first time period, wherein the third amount of light is less than the second amount of light, wherein a first microlens covers a respective edge pixel, wherein the first microlens covers a portion of the center pixel and diverts incident light from the center pixel to the respective edge pixel, and wherein the plurality of edge pixels, the plurality of corner pixels, and the center pixel have respective light collecting areas of the same size.

13. The image sensor of claim 12 , wherein a second microlens covers a second respective edge pixel of the plurality of edge pixels and wherein the second microlens covers a portion of the center pixel and diverts incident light from the center pixel to the second respective edge pixel.

14. The image sensor of claim 13 , wherein a third microlens covers a third respective edge pixel of the plurality of edge pixels, wherein the third microlens covers a portion of the center pixel and diverts incident light from the center pixel to the third respective edge pixel, wherein a fourth microlens covers a fourth respective edge pixel of the plurality of edge pixels, and wherein the fourth microlens covers a portion of the center pixel and diverts incident light from the center pixel to the fourth respective edge pixel.

15. The image sensor of claim 13 , wherein fifth and sixth microlenses cover the remaining pixels in the pixel block.

16. The image sensor of claim 12 , wherein the pixel block further comprises:
a plurality of color filters, wherein a color filter of the plurality of color filters is formed above the center pixel, wherein the color filter formed above the center pixel is surrounded by a shielding element, and wherein the center pixel is surrounded by an isolation structure.

17. The image sensor of claim 12 , further comprising:
a second pixel block that has a second microlens configuration formed over the second pixel block, wherein the microlens configuration is different from the second microlens configuration.

Assignees

• Semiconductor Components Ind Llc

Inventors

• Borthakur Swarnal
• Boettiger Ulrich

Classifications

• H04N23/672

  based on the phase difference signals · CPC title

• H04N25/585

  with pixels having different sensitivities within the sensor, e.g. fast or slow pixels or pixels having different sizes · CPC title

• H04N25/134

  based on three different wavelength filter elements · CPC title

• H04N25/704

  Pixels specially adapted for focusing, e.g. phase difference pixel sets · CPC title

• H04N25/57 Primary

  Control of the dynamic range · CPC title