| 摘要 |
PROBLEM TO BE SOLVED: To meet demands for faster, high-density recording, etc., without sacrificing cost, performance, etc., by suppressing deviation of a light modulated waveform from a desired value due to distortion, skew, etc., of a light modulation control signal waveform. SOLUTION: A state machine 150 has a plurality of states corresponding to a multi-valued irradiation level when an LD is driven to emit light with the multi-valued irradiation level so as to record and reproduce information to and from a recording medium; and a modulation signal indicating transition of states is generated according to variation in the multi-valued irradiation level of the LD and the driving current of the LD is modulated corresponding to the states. |
