Abstract

Optical storage disks with multiple data layers¹ offer large potential increases in capacity over standard single layer disks. In this approach individual data layers are spaced far enough apart so that any significant crosstalk is avoided and arc accessed by moving the objective lens in the focus direction. The large numerical aperture of the objective allows data layer separations that arc small enough to permit access by standard focus actuators in existing optical storage mechanisms. This scheme requires no change in the CD format and is fully backward compatible with CD Audio, CD ROM and CDR disks and provides a favorable development path for the delivery of compressed video. Two times current CD capacities would enable playback of MPEG 1 compressed full length movies from a single disk, while higher capacities would permit improvements of the video quality.

© 1994 Optical Society of America