ERASABLE OPTICAL DATA STORAGE MEDIUM HAVING A ZONED INTEGRAL RECORDING LAYER

摘要

An erasable optical data storage medium has an integral recording layer (11) including an expansion zone (18) and a retention zone (16) having different optical and thermal-mechanical properties. A uniform integral layer of dyed polymer material (14) has the dye leached out of the surface region and a second dye diffused into the surface region to create a retention zone (16). The retention zone (16) has a higher elastic modulus and glass transition temperature than the underlying expansion zone (18) and is adapted to absorb and transmit light which is centered about a different wavelength than the expansion zone (18). The medium is adapted to be used with a non-ablative and non-vesicular method to create and erase optically detectable deformations (24) in the retention zone.