HANDS FREE OPTICAL SCANNER TRIGGER

摘要

A method and apparatus for detecting an object within the field of view of an optical reader, such as a bar code scanner (102). Object detection is determined by a software algorithm that may be embedded in a controller (104) or microprocessor contained within the scanner. The object detection software algorithm uses a current trigger threshold to determine whether there is a change in the amount of reflected light energy (116) sufficient to indicate the presence of motion in the scanner (102) field of view. The system may normalize random noise within a scanner's circuitry and accommodate varying degrees of reflectivity of target materials, without requiring additional circuitry or reflective tape to accurately detect an object.