Bar code reading system

Abstract

Abstract PURPOSE:To exclude an undesired information such as a stain or the like through a simple constitution, by detecting the ratio of width between an immediately front bar and an immediately rear bar. CONSTITUTION:A photodetector 4 receives the reflected light irradiated to a card 1 to convert the light into an electric signal of the pattern corresponding to the bar code written on the card 1 and supplies the electric signal to a cunter 8 via a slicing circuit 5, a delaying circuit 6 and an exclusive OR circuit 7. A counter 10 measures the bar code width and counts the number of clock pulses supplied from a clock pulse generator 11. The output of this count is supplied to a deciding part 12, and a comparison is given to the widths of adjacent bars. When the bar width is within a prescribed range, a gate 17 is opened to supply the contents of a memory 14 to a memory 18 of a demodulating part.

Inventors

• 👤 Shunji Kitagawa
• 👤 Hiroyuki Ikeda

Bibliographic Details