METHOD AND APPARATUS FOR READING BAR CODED DATA WHEREIN THE LIGHT SOURCE IS PERIODICALLY ENERGIZED

摘要

A method and apparatus for reading bar coded data for entry into portable data collection systems. The data is read by an optical wand wherein the light source is automatically and periodically energized for saving the energy of the system. The D.C. offset voltages are determined and stored in an up/down counter during reading or sampling intervals while the analog signal processing circuits are periodically de-energized. The light source is also calibrated to maximize the power savings and minimize reading errors.