Patent ID: 7193949

Claim:
A method for recording data in a write-once type optical recording medium including a substrate and at least one recording layer formed on the substrate, the method comprising: determining a pulse train pattern so that a level of a pulse is switched from a level corresponding to a level of a recording power to a level corresponding to a level of a bottom power in accordance with at least one of a length of a first recording mark, a length of a blank region to be formed immediately after formation of the first recording mark and a length of a second recording mark formed subsequent to the formation of the first recording mark; modulating a power of a laser beam in accordance with the thus determined pulse train pattern; projecting the laser beam onto the optical recording medium; and forming the first recording mark; wherein a delay time period T 3 between a fall time of a data pulse corresponding to the first recording mark and a time at which the level of a pulse is switched from the level corresponding to the level of the recording power to the level corresponding to the level of the bottom power in the pulse train pattern used for forming the first recording mark is set so as to satisfy a formula below, wherein T 3 (x 1 , y, z) is a delay time period T 3 in the case of forming the first recording mark having a length x 1 , the blank region having a length y after the formation of the first recording mark and the second recording mark having a length z and T 3 (x 2 , y, z) is a delay time period T 3 in the case of forming the first recording mark having a length x 2 , the blank region having a length y after the formation of the first recording mark and the second recording mark having a length z, where x 1 is smaller than x 2 T 3( x 1 , y, z )> T 3( x 2 , y, z ).