| 摘要 |
PROBLEM TO BE SOLVED: To increase the recording density without shortening the wavelength of a light source for recording. SOLUTION: A multilevel recording is enabled by a step-wise pit pattern by forming a synchronizing signal pattern 12 on an optical information recording medium 11, controlling a positional relation between a recording head 27 and the optical information recording medium 11 based on a synchronizing signal obtained by reading the synchronizing signal pattern 12, and multiply exposing the medium sequentially by a predetermined pattern. |
