Target finder in electro-optical scanners

摘要

A target bearing a coded indicium is found by a system for electro-optically reading indicia. Upon the determination that the indicium is located within a range of working distances relative to a hand-held housing, a user is prompted that the indicium is ready to be read. A sonic signal is transmitted by a ranger, and a return echo from the indicium is received. An auditory prompt, such as a single tone or a series of tones, advises the user that the indicium is within range.