Variable Intensity Illumination Scanner Calibration System
Original Publication Date: 1979-Feb-01
Included in the Prior Art Database: 2005-Feb-19
Reflectivity measurements made on a document to be scanned by a photodiode matrix establish a calibration setting for a variable intensity light source. The feedback system allows maximum video signal from the matrix for any given document independent of background reflectivity and print density, as may be useful for optical character reading.