SYSTEM, CIRCUIT, AND METHOD FOR EDGE DETECTION IN A BINARY OPTICAL CODE

摘要

Systems process an input signal, derived from a binary optical code, having a series of multiple successive local peaks of the same given polarity. The circuit comprises a peak detector, a node in the peak detector, and a set-reset flip-flop. The peak detector has an input receiving the input signal and produces an output that approximately tracks the input signal while it is sloping in the direction of the given polarity and that approximately holds near those local peaks having successively larger magnitude. A node in the peak detector has a voltage indicative of whether the peak detector is in a tracking or holding state. The set-reset flip-flop has a set input connected to the node, whereby the output of the flip-flop is high when the peak detector is in a tracking state. The circuit is useful for qualifying optical edges in a bar code.