| 摘要 |
<p>PURPOSE:To confirm easily the residual amount of a tape from a cassette holder by fitting a grating member to an opening to confirm the magnetic tape residual quantity of a cassette holder in order to shield external light other than the light emitted from a light emitting element. CONSTITUTION:An external light shielding member 7 is provided to the opening of the tape residual quantity confirmation provided to the cassette holder. The external light shielding member 7 prevents the arrival of external light A to a photodetector 4 and receives only the light from the light emitting element 3. Thus, the tape residual quantity is confirmed easily and abnormal tension applied to the magnetic tape through the mis-detection of the start or end of the magnetic tape due to the effect of external light is avoided.</p> |
