Patent ID: 7561194

Claim:
A method for reducing charge diffusion crosstalk in an image sensor having a plurality of pixels disposed in a substrate and a color filter mask positioned over the plurality of pixels such that each pixel is covered with a monochromatic filter of a certain color and that no two adjacent pixels have filters of the same color, wherein the certain colors of the monochromatic filters comprise red, green and blue, the method comprising: sampling a first pixel to produce a first measured pixel value; sampling a group of adjacent pixels immediately surrounding the first pixel to produce adjacent measured pixel values; applying diffusion crosstalk coefficients applicable to the first pixel to the measured value of the first pixel and the measured values of the adjacent pixels to generate a calculated first pixel value that is corrected for charge diffusion crosstalk, wherein the crosstalk coefficients are applied using the equations [ R G B ] = [ 1 - 4 ⁢ k rg - 4 ⁢ k rb 4 ⁢ k g ⁢ ⁢ r 4 ⁢ k br 2 ⁢ k rg 1 - 2 ⁢ k gb - sk gr 2 ⁢ k bg 4 ⁢ k rb 4 ⁢ k gb 1 - 4 ⁢ k bg - 4 ⁢ k br ] ⁡ [ R o G o B o ] where R, G, and B denote measured values of red, green and blue pixels, Ro, Go and Bo denote corrected values of red, green and blue pixels, k rg denotes the crosstalk from a red pixel to a green pixel, k rb denotes the crosstalk from a red pixel to a blue pixel, k bg denotes the crosstalk from a blue pixel to a green pixel, k br denotes the crosstalk from a blue pixel to a red pixel, k gb denotes the crosstalk from a green pixel to a blue pixel, and k gr denotes the crosstalk from a green pixel to a red pixel.