| 摘要 |
PURPOSE:To protect the optical recording medium on the optical tape against external light and to obviate the loss of recording even if the top cap of a cassette is opened by forming a reflecting layer and a light shielding layer on the optical recording medium and disposing the light shielding layer in the outward direction of the cassette with respect to the optical recording medium. CONSTITUTION:The optical recording medium 2 consisting of a photochromic material, the reflecting layer 3 and the light shielding layer 4 are successively laminated on a tape base 1 and the light shielding layer 4 is disposed in the outward direction of the cassette with respect to the optical recording medium 2. Since the light coming from the light shielding layer 4 side to the optical recording medium 2 is thereby shut off, the optical recording medium 2 on the optical tape can be protected against the external light simply by shutting off the tape base 1 side of the part not wound on the tape reel of the optical tape from the light. The loss of the recording is obviated even if the top cap of the cassette is opened. |
