| US 7,564,750 B2 | ||
| Reproducing apparatus | ||
| Yasuyuki Tanaka, Suginami-ku (Japan); and Shinichi Yamashita, Hachioji (Japan) | ||
| Assigned to Canon Kabushiki Kaisha, Tokyo (Japan) | ||
| Filed on Oct. 27, 2005, as Appl. No. 11/262,026. | ||
| Claims priority of application No. 2004-320635 (JP), filed on Nov. 04, 2004; and application No. 2005-123521 (JP), filed on Apr. 21, 2005. | ||
| Prior Publication US 2006/0092790 A1, May 04, 2006 | ||
| Int. Cl. G11B 7/005 (2006.01) | ||
| U.S. Cl. 369—47.28 [369/53.34] | 15 Claims |
| 1. A reproducing apparatus comprising:
a reading unit configured to apply an optical beam to a track which is formed on a disk recording medium and wobbles at a
predetermined cycle and to generate a wobbling signal containing a frequency component associated with the wobbling cycle
of the track and a reproduced signal containing information data recorded on the track;
a clock generation unit configured to generate a clock having a frequency associated with the wobbling cycle using the wobbling
signal, the clock generation unit including a reference signal generation unit configured to generate a reference cycle signal
of the frequency associated with the wobbling cycle, a detection unit configured to detect a frequency difference between
the reference cycle signal and the wobbling signal, a sine wave signal generation unit configured to generate a sine wave
signal based on an output of the detection unit, and a multiplication unit configured to multiply a frequency of the sine
wave signal to generate the clock; and
a control unit configured to detect a phase difference between the reproduced signal and the clock, and to control a generation
operation of the clock generation unit using the phase difference, the control unit changing a phase of the reference cycle
signal and a phase of the sine wave signal based on the phase difference.
|