| 摘要 |
<p>PURPOSE:To easily and surely discriminate a leader tape part by detecting the variation of the reception quantity of detecting light in a light receiving part. CONSTITUTION:Light emitting parts 23A and 23B which emit detecting light LA21A and LA21B and light receiving pats 24A and 24B which receive these detecting light LA21A ad LA21B are provided. A recording medium 6 like a tape consisting of a recording part having a prescribed light transmissivity and a leader tape part having a higher light transmissivity is so loaded that it traverses the optical paths of detecting light LA21A and LA21B, and this medium 6 is run and the quantities of detecting light received by light receiving parts 24A and 24B are detected to discriminate the leader tape part. When the variation of the reception quantity of detecting light LA21A (LA21B) in the light receiving part 24A (24B) exceeds a prescribed level, the leader tape part is discriminated. Thus, the leader tape part is always surely detected.</p> |
