OPTICAL SCANNING QUALITY JUDGEMENT DEVICE FOR BAR CODE SCANNER

摘要

PURPOSE: To surely judge the quality of an optical scanning pattern by detecting scanning light projected from a read window and transmitted through the specified light transmission part of a gauge plate and analyzing the scanning light detection signals. ;CONSTITUTION: The gauge plate 20 capable of being disposed opposite to the read window 11 of a bar code scanner 10 is formed from a polycarbonate resin plate with improved light transmissivity and is provided with the light transmission part 21 formed in a pattern corresponding to a normal optical scanning pattern and a light interruption part 22 formed in a range excluding the light transmission part 21. Then, when output light from the read window 11 is the normal optical scanning pattern, it is transmitted through the light transmission part 21, detected in a scanning light detection means 42 and judged as normal in the case of normal power. It is judged as defective when the optical scanning pattern is not the normal power. Further, when a part of the optical scanning pattern lacks or when it is shifted from the normal optical scanning pattern, it is judged as defective.;COPYRIGHT: (C)1996,JPO