| 摘要 |
PROBLEM TO BE SOLVED: To accurately measure an asymmetry value (a β value) employing a simple control in a running OPC which conducts power correction for the power of a recording laser in real time while conducting recording. SOLUTION: Pits are formed on a recording surface of an optical disk 2 by 0th order diffracted light beams to record information. Then, RF signals S' are detected from the pits already formed on a track that is one track inside the adjacent track, on which the 0th order diffracted light beams are currently conducting recording, by -1st order diffracted light beams that irradiate an inside land adjacent to the track being irradiated by the 0th order diffracted light beams so as to compute the asymmetry value. |
