Patent ID: 7254101
Filing Date: 2007-08-07
Classification: G11B

Abstract:
1. A method for determining a pulse train pattern including a pulse whose level is set to a level corresponding to a level of a recording power set to be higher than a reproducing power and a pulse whose level is set to a level corresponding to a level of a bottom power set to be higher than the reproducing power and adapted for modulating the power of a laser beam used for recording data in a write-once type optical recording medium, the method comprising: varying the level of the bottom power while fixing the recording power at a predetermined level; modulating the power of the laser beam in accordance with the pulse train patterns to record first test signals in the write-once type optical recording medium; reproducing the first test signals; determining an optimum level of the bottom power based on the thus reproduced first test signals; varying the level of the recording power while fixing the bottom power at the optimum level; modulating the power of the laser beam in accordance with the pulse train patterns to record second test signals in the optical recording medium; reproducing the second test signals; and determining an optimum level of the recording power based on the thus reproduced second test signals.