Browse Prior Art Database

Variable Intensity Illumination Scanner Calibration System

IP.com Disclosure Number: IPCOM000066224D
Original Publication Date: 1979-Feb-01
Included in the Prior Art Database: 2005-Feb-19

Publishing Venue

IBM

Related People

Authors:
Dattilo, AJ Nielson, MC [+details]

Abstract

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.