Patent ID: 6450405
Filing Date: 2002-09-17
Classification: G06K

Abstract:
An optical code reader comprising:a scanning mechanism for radiating beams for scanning a code to be read; a beam receiving element for receiving reflected beams from a scanned object and outputting an electric signal; a differentiation unit for differentiating said electric signal and outputting a differentiation signal; a slice level generation unit for outputting a slice level which is made by synthesizing a first slice level and a second slice level, said first slice level having a first slice ratio which is constant with respect to a peak value of an amplitude of said differentiation signal and said second slice level having a second slice ratio, which varies according to said peak value, with respect to said peak value, where first and second slice ratios are ratios between a slice level and said differentiation signal; and a comparison unit for comparing the level of said differentiation signal with said synthetic slice level and outputting a binarized signal.