APPARATUS FOR AND METHOD OF ELECTRO-OPTICALLY READING A TARGET IN THE PRESENCE OF AMBIENT LIGHT BY DETECTING AND SUPPRESSING THE AMBIENT LIGHT

摘要

A target is read in the presence of ambient light. A scan component scans a laser beam across the target. A detector assembly detects and converts return laser light from the target into an information signal bearing information related to the target, and concomitantly detects and converts the ambient light into an ambient light signal. The assembly includes a first photodetector for generating a first output signal comprised of the information and the ambient light signals, a detector lens for focusing and directing the return laser light substantially onto the first photodetector, and a second photodetector for generating a second output signal substantially comprised of the ambient light signal. Signal processing circuitry processes the output signals to determine a magnitude of the ambient light signal, and suppresses the ambient light signal when the determined magnitude of the ambient light signal at least equals a threshold.