| 摘要 |
1300193 Coating by vapour depositing ROBERT BOSCH GmbH 29 April 1971 [2 May 1970] 12172/71 Heading C7F [Also in Division G1] A recording carrier 11 has a relatively thick dielectric substrate 21 and a relatively thin metallic layer 22 the roughness depth (i.e. the difference in height between crests and troughs) of the surface of the substrate 21 covered by the layer 22 being greater than the thickness of the layer 22. The depth and thickness may lie respectively in the ranges 2 to 8Ám and 0À01 to 0À5Ám. The metallic layer may be vapour deposited on the substrate which may be made of synthetic material and which may comprise two layers one chosen for mechanical strength the other for high dielectric constant. The breadth of the electrode 13 for burning a trace by the passage of an electric current, should be greater than the roughness depth of the carrier. Alternatively the carrier may be used for recording traces produced by electrolytic etching or by heating with a laser beam. |
