Patent ID: 6914866
Filing Date: 2005-07-05
Classification: G11B

Abstract:
1. An optical information recording method comprising: irradiating a phase-change recording layer of an optical information recording medium with a laser light beam to record or rewrite information in the phase-change recording layer by mark edge recording, wherein the optical information recording medium includes a transparent substrate having at least one of concentric grooves and a spiral groove, and the phase-change recording layer is located overlying the transparent substrate, and wherein irradiation is performed along the at least one of concentric grooves and a spiral groove, wherein a 0 signal having a signal width nT is recorded or rewritten using continuous laser light having a power level Pe, and a 1 signal having a signal width nT is recorded or rewritten using a light pulse train which has a first pulse portion fp having a power level Pw and a pulse width xT, a multi-pulse portion mp in which a number (n−n′) of high level pulses each having a power level of Pw′ and a pulse width yT, and, if (n−n′)>1, a low level pulse which is located between two of the high level pulses and has a power level Pb and a pulse width (1−y)T are applied, and an end pulse portion ep having a power level Pb′ and a pulse width zT, wherein T is a clock time, each of n and n′ is independently a positive integer and n is greater than n′, and wherein each of Pw and Pw′ is greater than Pe, Pe is greater than each of Pb and Pb′, and at least one of x, y and z is in a range as follows: and wherein the irradiating step is performed while the optical information recording medium rotates at a linear speed of from V m/s to 3V m/s, and wherein V is from 3 to 13.