PURPOSE: To obtain an optical reader with high reliability which accurately reads out the code information of the latent image mark by restricting the angle of intersection of the optical axis of a light projecting means and the optical axis of a photodetecting means on the latent image mark below a specific value.
CONSTITUTION: The focal length of a lens body 11 is designed to be a little bit ahead of the detection opening part of an opening frame body 3 so that when the detection opening part is nearby the latent image mark 15, the mark can be read without securely attaching the detection opening part to a mark carrier 14. Then this optical reader is constituted so that the angle of intersection of the optical axis of the projecting means 4 and the optical axis of the photodetecting element 8 on the latent image mark 15 is ≤40°. Thus, the angle θof intersection of the optical axis of the projecting element 4 and photodetecting element 8 on the latent image mark 15 is decreased to ≤40° or a narrow angle, thereby reducing the influence of an irregularity in distance between the projecting element 4 and photodetecting element 8, and the latent image mark 15 as much as possible.
| JP2738795 | TOUCH SCANNER |
| JPH103709 | REMOTE CONTROL METHOD AND FACSIMILE DEVICE |
ISHIZUKA TOMOAKI
OSHIMA TOSHIO
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