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AssigneeXerox Corporation
InventorsFred F. Hubble, III, Joel A. Kubby
Estimating the term…
An improved spectrophotometer for non-contact measuring of the colors of colored target areas, especially, test patches on moving printed test sheets in an unrestrained normal output path of a color printer, which test patches may be sequentially angularly illuminated with multiple different colors, with a photosensor providing electrical signals in response, the spectrophotometer having a lens system for transmitting that reflected illumination from the test patch to the photosensor with a lens magnification ratio of approximately one to one. The exemplary spectrophotometer provides noncontact color measurements of moving color target areas variably displaced therefrom within normal paper path baffle spacings, with a displacement insensitivity of at least 6 millimeters about a nominal target to spectrophotometer separation.
In a color correction system for a color printer with an output path for printed color sheets, including printed test sheets with multiple printed color test patches printed in a linear array in the movement direction of said printed test sheets by said color printer, in which a spectrophotometer is mounted in said printer output path for sensing the colors printed on a test patch on a test sheet as said test sheets are moving past said spectrophotometer in said printer output path, wherein said spectrophotometer includes a plurality of illumination sources with a sequential actuation circuit for sequentially illuminating a said test patch with different illumination colors, a photodetector sensor system with at least one photosensor providing electrical output signals, and a lens system for transmitting said illumination from said test patch to said photodetector sensor system, whereby said photodetector sensor system provides different said electrical output signals in response to viewing said different illumination colors from said sequential illuminations of said test patch by said plural illumination sources, wherein said spectrophotometer is mounted at one side of said printer output path for providing non-contacting said viewing of said test patches with said spectrophotometer spatially displaced from said test sheets, and wherein said lens system for transmitting said illumination from said test patch to said photodetector sensor system provides substantial insensitivity to variations in said displacement between said spectrophotometer and said test sheets in said electrical output signals of said photodetector sensor system.
An improved spectrophotometer for measuring the color of a color target area by illuminating the target area with a plurality of different colors and detecting the illumination reflected from said illuminated target area by said different colors, with a photodetector sensor system providing electrical signals in response thereto, and with a lens system for transmitting said illumination reflected from said color target area to said photodetector sensor system, the improvement wherein:
A spectrophotometer for measuring the color of a color target area displaced from said spectrophotometer, comprising:
Dependencies are inferred from the claim text.