| 摘要 |
<p>PURPOSE:To surely detect a leader tape part by setting the discrimination reference value of the quantity of translucent light at the time of discriminating the leader tape part of a recording medium based on the quantity of detecting light which is detected without loading the recording medium. CONSTITUTION:Light emitting parts 23A and 23B irradiated with detecting beams LA21A and LA21B and light receiving parts 24A and 24B which receive detecting light are provided. A recording medium 6 like a tape consisting of a recording part having a prescribed light transmitivity and a leader tape part having a higher light transmitivity is so loaded that it traverses the optical paths of detecting beams LA21A and LA21B, and this medium 6 is run to detect the quantities of detecting beams LA21A and LA21B received by the light receiving parts 24A and 24B, thereby discriminating the leader tape part. The quantities of detecting beams LA21A and LA2B are detected without loading the recording medium 6, and the discrimination reference light quantity value for discrimination of the leader tape part of the recording medium 6 is set based on these quantities of beams. Thus, the leader tape part is surely discrimi nated.</p> |
