| 摘要 |
PROBLEM TO BE SOLVED: To provide a transparent body detecting sensor capable of getting rid of influence of the lens effect of a transparent body, and stably detecting the transparent body when the received light quantity of a light receiving part fluctuates due to dirt on lenses provided in a light projection part, the light receiving part, and an optical path, and when it is used for a long period of time. SOLUTION: This transparent body detecting sensor 10 functions as a threshold value setting means to set a second threshold value level region for a microcomputer to determine a non-detected state. When the microcomputer 16 sets the second threshold value level region, it is set so that a range of values shifted to plus and minus respectively with respect to the received light quantity level under the non-detected state in the past by a prescribed quantity (that is M %) is used as the second threshold value level region. COPYRIGHT: (C)2008,JPO&INPIT
|
