Color filter including diamond-shaped pixels

• US 9,716,868 B1
• Filed: 03/03/2016
• Issued: 07/25/2017
• Est. Priority Date: 03/03/2016
• Status: Active Grant

• Current Assignee: Omnivision Technologies Incorporated (Will Semiconductor Co., Ltd. Shanghai)
• Original Assignee: Omnivision Technologies Incorporated (Will Semiconductor Co., Ltd. Shanghai)
• Inventors: Mao, Duli
• Primary Examiner(s): Prabhakher, Pritham
• Application Number:
  US15/060,187
• Time in Patent Office: 509 Days
• Field of Search: 348280
• CPC Class Codes: H04N 2209/045 using mosaic colour filter
• CPC Class Codes: H04N 25/131 including elements passing infrared wavelengths
• CPC Class Codes: H04N 25/133 including elements passing panchromatic light, e.g. filters passing white light
• CPC Class Codes: H04N 25/135 based on four or more different wavelength filter elements
• CPC Class Codes: H04N 25/70 SSIS architectures; Circuits associated therewith

Abstract

Embodiments are described of a color filter array including a plurality of tiled minimal repeating units. Each minimal repeating unit includes a primary set of four rhombic color filters positioned so that at least two vertices of each rhombic color filter contact a vertex of an adjoining rhombic color filter and so that the four rhombic filters form a central interstitial space and four peripheral interstitial spaces, wherein the primary set includes at least one color filter with a first spectral photoresponse, at least one color filter with a second spectral photoresponse, and at least one color filter with a third spectral photoresponse. Each minimal repeating unit also includes a secondary set of rhombic filters, the secondary set comprising a rhombic filter positioned in the central interstitial space and rhombic filters positioned in three of the four peripheral interstitial spaces, wherein the rhombic filters in the secondary set have a fourth spectral photoresponse different than any of the first, second, and third spectral photoresponses.

Claims

1. A color filter array comprising:

a plurality of tiled minimal repeating units, each minimal repeating unit including at least;

a primary set of four rhombic color filters positioned so that at least two vertices of each rhombic color filter contact a vertex of an adjoining rhombic color filter and so that the four rhombic filters form a central interstitial space and four peripheral interstitial spaces, wherein the primary set includes at least one color filter with a first spectral photoresponse, at least one color filter with a second spectral photoresponse, and at least one color filter with a third spectral photoresponse; and

a secondary set of rhombic filters, the secondary set comprising a rhombic filter positioned in the central interstitial space and rhombic filters positioned in three of the four peripheral interstitial spaces, wherein the rhombic filters in the secondary set have a fourth spectral photoresponse different than any of the first, second, and third spectral photoresponses.

2. The color filter array of claim 1 wherein the first spectral photoresponse is red (R), the second spectral photoresponse is green (G), the third spectral photoresponse is blue (B), and the fourth spectral photoresponse is a non-visible photoresponse.

3. The color filter array of claim 2 wherein the non-visible photoresponse is infrared (IR), ultraviolet, or X-ray.

4. The color filter array of claim 1 wherein the first photoresponse is cyan (C), the second photoresponse is yellow (Y), the third photoresponse is magenta (M), and the fourth photoresponse is a nonvisible photoresponse.

5. The color filter array of claim 4 wherein the non-visible photoresponse is infrared (IR), ultraviolet, or X-ray.

6. The color filter array of claim 1 wherein rhombic filters from the secondary set are positioned in a north peripheral interstitial space, a south peripheral interstitial space, and at least one of an east peripheral interstitial space and a west peripheral interstitial space.

7. The color filter array of claim 6 wherein rhombic filters from the secondary set are positioned in a north peripheral interstitial space, a south peripheral interstitial space, and an east peripheral interstitial space.

8. An image sensor comprising:

a pixel array including a plurality of individual pixels;

a color filter array positioned over the pixel array such that each individual pixel in the pixel array is optically coupled to a corresponding filter of the color filter array, the color filter array comprising a plurality of tiled minimal repeating units, each minimal repeating unit including at least;

a primary set of four rhombic color filters positioned so that at least two vertices of each rhombic color filter contact a vertex of an adjoining rhombic color filter and so that the four rhombic filters form a central interstitial space and four peripheral interstitial spaces, wherein the primary set includes at least one color filter with a first spectral photoresponse, at least one color filter with a second spectral photoresponse, and at least one color filter with a third spectral photoresponse; and

a secondary set of rhombic filters, the secondary set comprising a rhombic filter positioned in the central interstitial space and filters positioned in at least three of the four peripheral interstitial spaces, wherein the rhombic filters in the secondary set have a fourth spectral photoresponse different than any of the first, second, and third spectral photoresponses;

readout circuitry coupled to the pixel array to read out signals from the individual pixels; and

function logic coupled to the readout circuitry to process the signals read from the individual pixels.

9. The image sensor of claim 8 wherein the first spectral photoresponse is red (R), the second spectral photoresponse is green (G), the third spectral photoresponse is blue (B), and the fourth spectral photoresponse is a non-visible photoresponse.

10. The color filter array of claim 9 wherein the non-visible photoresponse is infrared (IR), ultraviolet, or X-ray.

11. The image sensor of claim 8 wherein the first photoresponse is cyan (C), the second photoresponse is yellow (Y), the third photoresponse is magenta (M), and the fourth photoresponse is a non-visible photoresponse.

12. The image sensor of claim 11 wherein the non-visible photoresponse is infrared (IR), ultraviolet, or X-ray.

13. The image sensor of claim 8 wherein rhombic filters from the secondary set are positioned in a north peripheral interstitial space, a south peripheral interstitial space, and at least one of an east peripheral interstitial space and a west peripheral interstitial space.

14. The image sensor of claim 13 wherein rhombic filters from the secondary set are positioned in a north peripheral interstitial space, a south peripheral interstitial space, and an east peripheral interstitial space.

15. The image sensor of claim 8 wherein the shape of each filter substantially matches the size of its corresponding pixel.

16. The image sensor of claim 8 wherein the readout circuitry comprises:

a first readout circuit coupled to pixels that are optically coupled to filters from the primary set; and

a second readout circuit coupled to pixels that are optically coupled to filters from the secondary set;

wherein pixels that are optically coupled to filters from the primary set can be read separately and independently from pixels that are optically coupled to filters from the secondary set.