| 摘要 |
<p>PURPOSE:To obtain a conversion pulse with fidelity to a pattern from an analog signal independently of an interval and an angle between a bar code and a reader, and dirt of the bar code, by obtaining a conversion pulse from a reading analog signal of a bar at the scanning initial of the bar code reader. CONSTITUTION:An operational amplifier 2 amplifies an output signal Ea of a bar code reader. Further, a reference voltage circuit 3 consisting of diodes D1 and D2, capacitors C1-C3 and resistors R1-R3 receives an output signal of the amplifier 2 and generates a reference voltage Er. A comparator 4 converts an analog signal Ea' from the amplifier 2 based on the reference voltage given from the reference voltage circuit 3, into a pulse corresponding to a bar code pattern. The pulse generated from an output terminal 5 is processed at an electronic computer.</p> |
