ERASABLE OPTICAL DATA STORAGE MEDIUM HAVING AN EMBEDDED SERVOTRACK AND A SUBSURFACE RECORDING INTERFACE

摘要

An erasable optical data storage medium (10) has an embedded servo track (14) and a subsurface recording interface (24). An erasable recording structure having two dyed polymer layers (22, 26) is separated from the servo track by a compression layer (20). The servo track is formed in a hard substrate (12) which provides mechanical support for the medium. The medium is adapted to form non-vesicular data bumps (28) projecting into the compression layer (20) when exposed to a write laser beam of predetermined wavelength projected through the substrate (12) and compression layer. The embedded servo track (14) and recording interface (24) are sufficiently close to each to be read simultaneously in the same focal plane.