摘要 |
A gloss sensor for determining the gloss of a surface, for example, of moving paper being produced by a paper making machine. The gloss sensor normally is installed in a scanner which scans the moving paper in a crosswise direction. It includes a standard TAPPI light source which impinges upon the paper at a specified angle and the intensity of the detected reflected light is related to gloss. Calibration is provided by an oscillating angle light source which with the same lamp has a direct reference path to the detector. Compensation for tilting or shifting paper is provided by the same oscillating light source which when the paper tilts or shifts still allows a reflected light beam to reach the detector. Change of angle from the standard TAPPI angle due to parallel paper shifts is compensated.
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