Patent ID: 6746746
Filing Date: 2004-06-08
Classification: G11B,Y10T

Abstract:
A laser beam optical recording medium having several read/write levels, comprising a first semi-transparent level and at least a second level, the first level being close to the laser transmitting source, wherein each level comprises a phase changing material layer with two stable states controlled by a laser beam, and wherein the phase changing material layer of the first level is an alloy of the formula:[(GeyTe1-y)a(SbzTe1-z)1-a]1-b(In1-xTex)b wherein0.4&lE;y&lE;0.6 0.3&lE;z&lE;0.5 0.4&lE;x&lE;0.6 0.3&lE;a&lE;0.5 0.01&lE;b&lE;0.3, and wherein the first level has a reflection coefficient in the range from 10% to 30%, a transmission coefficient at least 45%, a writing power lower than 23 mW and an erasing power lower than 10 mW.