Gain calibration device and method for differential push-pull tracking error signals
US7023767B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 14, 2002 |
| Grant date | Apr 4, 2006 |
| Priority date | — |
| Expiry date | Jan 21, 2024 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B7/0956
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A gain calibration device and method for differential push-pull (DPP) tracking error signals in an optical storage system is provided. The gain calibration method processes the synthesized gain (SPPG) of the sub beam in the DPP tracking error signal components with respect to the main beam. The calibration theorem resides in controlling the objective lens of the pick-up head to form a lens-shift or controlling the tilt of the objective lens relative to the optical disc to make the synthesized DPP tracking error signals generate a correspondingly signal variation owing to the optical path deviation. The synthesized gain is calibrated to make the signal variation a minimum value, and the calibrated synthesized gain is the optimum value. In the method and device of the invention, the optimum synthesized gain of the sub beam is precisely computed without the assumptions of equal intensity of the two sub beams and symmetrical positions of the two sub beams with respect to the main beam, and without knowing the ratio of the pitch between the two sub beams to the track pitch.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.