| 摘要 |
PROBLEM TO BE SOLVED: To keep the surface of a dustproof member always clean without performing cleaning operation for a bar code reader. SOLUTION: The external surface of a transparent window 14a of a dustproof plate 14 is coated with a translucent film 15 containing titanium oxide. When a bar code is read, an LED 11 is turned on and the translucent film 15 is subjected to optical catalysis with its light to decompose dust sticking on the transparent window 14a. |
