Importance

Loading Importance Indicators...

Abstract

A circuit for digitizing an analog signal generated from a photoelectric conversion of reflected light when scanning indicia having spatially-separated, light-reflective portions bounded by edges includes a differentiator for differentiating the analog signal. An inverter inverts the differentiated signal to generate an inverted signal. A negative peak detector detects negative amplitude peaks and a positive peak detector detects positive amplitude peaks of the differentiated signal and generate, respectively, a negative and positive peak signal. Adders are used to add the positive peak signal to the inverted signal, and the negative peak signal to the inverted signal. A comparator compares the two summed signals to the differentiated signal and generates pulse signals indicative of the edges of the analog signal. A controller, in response to the pulse signals, generates a digital signal corresponding to the indicia being scanned.

Loading the Abstract Image...

First Claim