| 摘要 |
A video disc record suitable for use with a video disc player apparatus is provided with a label for identifying the program material stored on the surface of the record. The label is formed in a machine readable format which comprises grooves in the surface of the record. In one format, whorls of a spiral groove on the surface of the record are spaced alternately with ungrooved areas on the surface. A readout apparatus comprises a light beam which is arranged to scan the grooved label and a detecetor which is arranged to sense the light beam reflected from the disc record surface. Light striking an ungrooved section is reflected in a substantially specular direction while light striking a grooved section is substantially scattered out of the specular direction. The detector is arranged to collect the light reflected into the specular direction. |
