Analysis of barcode digitization techniques
John Boles, Randall K. Hems · Proceedings of SPIE, the International Society for Optical Engineering/Proceedings of SPIE · 1991
Laser bar code scanners produce analog time varying signals which must be converted to logic level signals that can be decoded by a microprocessor. Proper decoding of the symbol is highly dependent on the circuit which converts the analog signal to a logic signal. The performance of a conversion circuit is partially determined by features of the detector signal due to the laser source the bar code symbol and ambient light. Characteristics which influence the selection of a digitizing circuit are presented.