SENSING AND IDENTIFYING INFORMATION WITHIN A LARGE INTERROGATION ZONE

摘要

A method and apparatus for extracting information from an object within a large interrogation zone by utilizing a retroreflective backing to define the location of the object and/or information on the object, and an apparatus designed to eliminate from consideration all specularly and diffusely reflected light otherwise present within the zone and thereby isolate the retroreflective backing within the zone. The apparatus then extracts the information which was defined by the retroreflective backing.