METHOD AND APPARATUS FOR REDUCING THE VISUAL DISCOMFORT OF THE ILLUMINATION GENERATED BY IMAGING SCANNERS

摘要

A method and apparatus for reducing the visual discomfort of the illumination generated by imaging scanners. The method includes (1) turning on a driving current for a illumination source during each of a series of exposure periods to provide illumination directed toward a target object; (2) capturing an image from the target object with photosensitive circuitry during at least one of the exposure periods; and (3) generating a pulse-width-modulation driving current that has a duty cycle changing with time between two consecutive exposure periods for making perceived gradual illumination changes between the two consecutive exposure periods. The duty cycle decreases from the value of 100% to a minimal value after each of the exposure periods and increases from the minimal value to the value of 100% before each of the exposure periods.