Optical storage apparatus
US6370094B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 12, 2000 |
| Grant date | Apr 9, 2002 |
| Priority date | — |
| Expiry date | Jun 12, 2020 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B7/0953
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An eccentricity amplitude of a medium in an eccentricity measuring unit and an eccentricity phase for a start position of one rotation are measured. A region from the start position to end position of one rotation of the medium which was measured is divided into a plurality of regions every predetermined rotational angle, addresses are sequentially allocated to those regions, a sine value of a rotational angle which is increased every predetermined rotational angle has been stored in each address in an eccentricity memory. A read control unit forms an address (a) in an eccentricity memory corresponding to a rotating position of the medium where a light beam is irradiated at present while using the start position of one rotation of the medium as a reference and reads out a corresponding sine value sin&thgr;a from the eccentricity memory by the designation of the address (a). An eccentricity correcting unit obtains an eccentricity amount (L) on the basis of the sine value read out from the eccentricity memory and the measurement values measured by the eccentricity measuring unit, thereby controlling a VCM positioner so as to set off the eccentricity amount (L).
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.