US 9,521,380 B2 · Imaging systems with clear filter pixels

Abstract

An image sensor may have an array of image sensor pixels arranged in color filter unit cells each having one red image pixel that generates red image signals, one blue image pixel that generate blue image signals, and two clear image sensor pixels that generate white image signals. The image sensor may be coupled to processing circuitry that performs filtering operations on the red, blue, and white image signals to increase noise correlations in the image signals that reduce noise amplification when applying a color correction matrix to the image signals. The processing circuitry may extract a green image signal from the white image signal. The processing circuitry may compute a scaling value that includes a linear combination of the red, blue, white and green image signals. The scaling value may be applied to the red, blue, and green image signals to produce corrected image signals having improved image quality.

Claims18

Dependent claims

A method of processing image signals using an image sensor having an array of image sensor pixels and processing circuitry, wherein the array of image sensor pixels includes a first group of image sensor pixels responsive to light of a first color, a second group of image sensor pixels responsive to light of a second color, and a third group of image sensor pixels responsive to light of a third color, the method comprising:

with the first group of image sensor pixels, generating first image signals in response to light of the first color;
with the second group of image sensor pixels, generating second image signals in response to light of the second color;
with the third group of image sensor pixels, generating third image signals in response to light of the third color;
and
with the processing circuitry, performing filtering operations on the first image signals, the second image signals, and the third image signals that increase noise correlations associated with first image signals, the second image signals, and the third image signals, wherein the filtering operations performed on the first, second, and third image signals that increase the noise correlations increase and decrease noise fluctuations in the first, second, and third image signals together in a correlated manner.

2 more elements

Dependencies are inferred from the claim text.

Imaging systems with clear filter pixels

Life of this patent

Imaging systems with clear filter pixels

Life of this patent

Abstract

Claims18