| 摘要 |
PURPOSE:To indicate the amount of a recorded part of an optical recording tape contained in an airtight case. CONSTITUTION:A tape 15 is formed by coating a plastic base with a Te-As-Se metallic film to about 1,000Angstrom thickness to record a digital signal by a laser beam, or by applying a mixed material of carbon and nitrocellulose onto the plastic base, and then contained in an airtight housing 10 for preventing dirt, such as dust. To the back wall 10d of the housing 10, an indication tape 30 is adhered to indicate a recording time corresponding to the recording time of the tape 15. |
