Abstract: An optical disc and an optical disc recording apparatus have an improved protection against undesired or illegal copying. Information on optical discs is arranged in sectors, which each has an address label. The address value of the address labels increases linearly from the start of the disc or from the start of the program area of the disc. The address labels of specific sectors, which may have an informationless content, are given different, e.g zero, address values, which prevent copying CD-ROM discs on a standard CD-Recorder apparatus. Said address labels may be stored in the main data stream or e.g. the subcode channel of a CD system.

Abstract: Viewer comprises a picture generating device which supplies black/white or color pictures, an optical fibre or fibre bundle for the transport of the optical pictures to a user who wears a display unit on the head. The display unit comprises a spectacles-like frame and optical means, such as lenses, grey filters, or transparent screens for making the pictures visible to the user. The user sees a "wide-screen" picture, but the actual dimensions of the picture are no more than a few centimeters. For the display of cinerama pictures the display unit comprises an angular position detector which supplies a signal in which the orientation of the head of the user is detected. The picture generating device then supplies a picture which is associated with the relevant orientation.