| 摘要 |
<p>Recording support for data in the form of relief-like projections and/or recesses, e.g. video disc, is covered by a protective coating on the data storage side. The coating is pref. bonded to the support only at the edges with gas-tigh joints, and in the cavities between support and coating is a gaseous medium, pref. dry air, or between support and coating is a layer of dye covering the whole surface of the support. Alternatively, between support and coating is a further light-transmitting layer of which the refractive index is different to that of the recording support. Where the cavities are filled with dry air, the surface of the support may be covered with a light-reflecting layer. The support is thus protected against mechanical effects causing erasure, and against dust and dirt causing misreading with optical means.</p> |
