摘要 |
A gloss sensor for determining the gloss of a surface, for example, of moving paper (11) being produced by a paper making machine. The gloss sensor (10) normally is installed in a scanner which scans the moving paper in a crosswise direction. It includes a standard TAPPI light source (14) which impinges upon the paper (11) at a specified angle and the intensity of the detected reflected light is related to gloss. Calibration is provided by an oscillation angle light source which with the same lamp has a direct reference path to the detector (36). Compensation for tilting or shifting paper is provided by the same oscillating light source which when the paper tilts of shifts still allows a reflected light beam to reach the detector (36). Change of angle from the standard TAPPI angle due to parallel paper shifts is compensated.
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