Optical storage apparatus
US6118739A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 9, 1998 |
| Grant date | Sep 12, 2000 |
| Priority date | — |
| Expiry date | Jan 9, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B7/0953
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An optical storage apparatus has an eccentricity measuring unit that measures an eccentricity amplitude of a medium and an eccentricity phase for a start position along one rotation of a disk. A region from the start position to an end position of one rotation of the medium which was measured is divided into a plurality of regions every predetermined rotational angle, and 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.theta.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 o…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.