| 摘要 |
<p>PURPOSE:To detect a bar code formed on a transparent or transluscent object to be processed as a pattern with good accuracy by irradiating light from the back side of the object to be processed where the bar code is formed to detect a transmitted light pattern by a photodetector. CONSTITUTION:The light from a light source 4 is projected on a mirror 7, its reflected light 8 irradiates the bar code 2 from the back side of a printed distributing board 1 and the tilt angle of the light source 4, the mirror 7 and the photodetector 3 is set so as to make this transmitted light 9 enter the photodetector 3. Further, the bar code 2 read sequentially by sliding a scanning mechanism 5 on a guard rail. The transmitted light 9 is formed on a photodetecting surface in the photodetector 3 by a lens 10 fitted to the tip of the photodetector 3. The detected signal is transmitted to a decode circuit 11, where the signal is decoded and read as information.</p> |
