MAKING COPIES OF INFORMATION TRACKS ON CARRIERS

摘要

Copying by photographic means of plates having coded audio and video information of a very fine structure. Use is made of an aromatic diazosulphide as light-sensitive system, wherein, after exposure, a metal nuclei image is produced by contact with metal salt, which metal nuclei image is at or below the surface and which is intensified by means of physical development to an externally reflective and, as such, readable image.