Patent ID: 6650416
Filing Date: 2003-11-18
Classification: G01J,G03G,H04N

Abstract:
A color correction system for a color printer having an output path for moving printed color sheets, including printed test sheets with printed color test patches, in which a spectrophotometer is mounted adjacent to said printer output path for sensing the colors printed on said printed color test patches on said printed test sheets as said printed test sheets are moving past said spectrophotometer in said output path, and in which said spectrophotometer comprises a limited plurality of illumination sources for sequentially illuminating said color test patches with different illumination spectra, a photodetector system, and an associated imaging lens system having an optical axis and an image plane, for providing electrical output signals in response to the color of said test patches from the reflection of a portion of said illumination of said color test patches by said illumination sources through said imaging lens system to illuminate said photodetector system, said photodetector system comprising at least one photodetector chip having a multiplicity of simultaneously so illuminated photo-sites including at least three different sets of simultaneously illuminated photo-sites having at least three different spectral responses providing at least three different said electrical output signals, wherein said photodetector chip is mounted on said optical axis of said imaging lens system and oriented substantially in said image plane of said imaging lens system to image said reflected illumination from said illuminated color test target area surface on said photodetector chip.