Patent ID: 6334572
Filing Date: 2002-01-01
Classification: G06K

Abstract:
A bar code reader having photoelectric conversion means for converting reflected light from a bar code into an electric signal wherein changing points at which a white or black stripe is changed to a black or white stripe in the bar code are detected so that the bar code is read, said bar code reader comprising:gate signal generating means for generating a gate signal indicating that a white or black stripe is changed to a black or white stripe in a bar code; maximum detecting means for detecting a changing point having a maximum value out of a plurality of detected changing points when the gate signal generated by said gate signal generating means indicates that a white or black stripe is changed to a black or white stripe; and mask signal generating means including a Fresnel Filter gate circuit for generating a mask signal which masks false changing points generated before said maximum detecting means detects the changing point having the maximum value, wherein, after the mask signal generated by said mask signal generating means is removed, the next detected changing point is determined to be a true changing point.