| 摘要 |
PURPOSE:To simplify assembling and adjustment at the time of production by providing an optical sensor provided with an optical transmission part and a photodetecting part related to the feeding side and winding side, respectively, reflecting light irradiated from the optical transmission part at the main surface of a tape and detecting the reflected light at the photodetecting part. CONSTITUTION:The 1st and 2nd optical sensors 20a, 20b are formed and provided with the optical transmission parts 21a, 21b and the photodetecting parts 25a, 25b respectively to form an optical sensor uniting transmission and reception parts. The 1st and 2nd optical sensors 20a, 20b are arranged on the external of a cassette 15 and fitted to the substrate of a video cassette tape recorder. The 1st and 2nd optical sensors 20a, 20b are positioned so that light irradiated from the optical transmission parts 21a, 21b of respective optical sensors 20a, 20b are passed through optical transmission windows 4, 14, reflected on the surface of the tape 10 respectively and then detected by the photodetecting parts 25a, 25b and connected to a prescribed detecting circuit (unshown).
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