| 摘要 |
PURPOSE:To obtain the optical tape which allows the smooth execution of recording and reproducing based on an exact tracking control and allows the reduction of the number of parts by providing a photochromic layer in addition to a recording layer and recording guide track patterns therein. CONSTITUTION:The optical tape 1 is constituted by having a base material 2, the photochromic layer 3 for recording the guide track patterns and the recording layer 4 for optically recording information in accordance with magneto-optical effect or photochromic phenomena, etc. The tape is formed by recording the guide track patterns on the photochromic layer 3 provided separately from the recording layer 4 in this constitution and, therefore, the degradation in the position density of the information in the recording layer 4 is obviated and the tracking control based on a laser light for making recording or reproducing on the recording layer 4 is executed. While a light source for recording the guide track patterns are separately needed in addition to a light source for recording and reproducing and a photodetector, etc., the provision of this light source on the optical head is not always required and, therefore, the number of parts is reduced. |
