| 摘要 |
<p>PURPOSE:To obtain the tape end detection mechanism of a cassette tape with which a mechanical deck side mechanism unit is not restricted even if the paths of light emitting part and light receiving part are lowered by the thickness reduction of a tape cassette and, further, the position allowance when the tape cassette is loaded onto the mechanical deck is not restricted. CONSTITUTION:A notched step part 20 is provided between the bottom and tape detecting hole 7 of a tape cassette 1 and a prism 21 is provided in the step part 20 and a light emitting device 30 is provided on the light entering part 26 on the side part of the prism main part 22 and the light emitting parts 28 and 29 are housed in the tape detecting hole 7. A light from the light emitting device 30 enters the prism main part 22 through the light entering part 26 and is reflected upward by a reflective plane 27 and is emitted to the left and right through the light emitting parts 28 and 29. The respective emitted lights are received by respective photodetectors 12 and 13.</p> |
