Patent ID: 7496021

Claim:
A recording medium in which first and second recording marks having lengths of n 1 ·Tw and n 2 ·Tw, respectively, are recorded by using recording pulses with the recording, power Pw, modulating an intensity of an irradiating light beam and modulating the lengths of a plurality of recording marks and spaces between each two said recording marks, and the recording power Pw is set to a value of Pwo to make a normalized parameter g(Pw) equal to gα, where g(Pw)=[D 2 (Pw)−D 1 (Pw)]/Tw, n 1 and n 2 are integers, n 1 <n 2 , and Tw is a period of a recording channel clock, measured lengths T 1 (Pw) and T 2 (Pw) of the first and second recording marks, respectively, are determined from reproducing and measuring the first and second recording marks, and deviations D 1 (Pw) and D 2 (Pw) of the measured lengths T 1 (Pw) and T 2 (Pw) from n 1 ·Tw and n 2 ·Tw, respectively, are determined as follows: D 1( Pw )= T 1( Pw )− n 1 Tw ; and D 2( Pw )= T 2( Pw )− n 2 Tw, wherein information indicating a value of gα is recorded in advance when fabricating the recording medium, and gα is a constant associated with properties of the recording medium.