| 摘要 |
A recoding playback apparatus and an optical disk are provided that allows reduction of a low frequency noise at a time of playback of a super resolution optical disk including small record marks whose size is below the diffractive limitation, to enhance quality of a playback signal. [Means for solution] The reflective beams from the optical disk are received by dividing into outer portion beams and a center portion beam, and a playback signal is created by combining such beams based on respective different gains. Based on received amounts of light or amounts of low frequency noise in respective light receiving regions, adjustment or determination of gain values is made, or the optical head apparatus is optically adjusted, whereby the low frequency noise is optimally suppressed. Further, a specific region is provided on the optical disk for making the foregoing adjustment. |
