Patent ID: 7323676

Claim:
Color photosensor ( 1 ) for sensing the color contents of incident light, comprising: a sensing unit ( 2 ) divided into four sensing areas ( 21 , 22 , 23 , 24 ) each sensing the color content of incident light and outputting a sensing current, a filter unit ( 3 ) comprising four filter elements ( 31 , 32 , 33 , 34 ) each being assigned one of said sensing areas, said filter elements comprising a cyan colored filter element, a yellow colored filter element and a magenta colored filter element, and a subtraction unit ( 4 ) for separately subtracting each of the three sensing currents outputted from the three sensing areas to which one of said colored filter elements is assigned, from the forth sensing current obtaining color signals proportional to the red, green and blue content of said incident light, wherein the four sensing areas ( 21 - 24 ) of said sensing unit are of unequal size and wherein the ratios of the sizes of said sensing areas compensate for infrared transmission differences of the filter elements.