METHOD AND SYSTEM FOR LASER WRITING MICROSCOPIC DATA SPOTS ON CARDS AND LABELS READABLE WITH A CCD ARRAY

摘要

A method and system for recording and storing digital data on optical memorycards (11) and labels using laser recording of optical storage media to createupdatable, high resolution, two-dimensional bar codes, storing about 15 tomore than 500 times as much digital data as the widely-adopted PDF-417, two-dimensional bar code. The optical storage media is of the DRAW (direct-read-after-write) type which requires no post processing. The optical storage mediais pre-formatted with tracks (74) to precisely locate the recorded microscopicdata spots (71). Groups of these microscopic data spots (71) form data barswhich in turn form data pixels (72, 73, 82, 83) whose dimensions are at leastfour times greater linearly and 16 times greater in area than the microscopicdata spots (71). The data pixels (72, 73, 82, 83) can be read withphotodetector arrays such as CCD arrays.