| 摘要 |
A laser scanner for reading a bar code having a plurality of bar code elements. The laser scanner includes a digitizer which receives as an input an analog signal from photodetector circuitry and digitizes the analog signal to produce a digital bar code pattern (DBP) signal representative of the bar code. The DBP signal is input to a decoder which reads and decodes the DBP signal thereby decoding the bar code. The digitizer imposes a short duration correction impulse on the DBP signal whenever successive edges of the same polarity are sensed wherein both of the edges are above a threshold level and further wherein the second edge is of greater magnitude than the first edge. When a correction impulse is received on the DBP signal by the decoder, the decoder corrects the DBP signal by removing the first edge and toggling on the second edge.
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