Patent ID: 8294777

Claim:
A chromatic coordinate converting apparatus, comprising: a storing unit storing information representing a plurality of chromaticity values of reference lights in a chromaticity coordinate system unique to a color sensor in advance; and a converting unit performing a chromatic coordinate conversion of a first chromaticity value being a chromaticity value generated by said color sensor into a second chromaticity value of a predetermined chromaticity coordinate system based on the information stored by said storing unit, wherein said converting unit comprises computing weighting ratios for a weighting synthesis of reference lights so that a chromaticity of said weighting synthesis of reference lights is equal to said first chromaticity value, and said converting unit obtains said second chromaticity value by estimating a spectroscopic characterization of incident light for said color sensor based on said information and said first chromaticity value, and thereafter, by representing the spectroscopic characterization by said predetermined chromaticity coordinate system.