Method and apparatus of measuring axial vibration of a disk recording medium
US6912184B2 · kind B2 · utility
2Cited by
3References
20Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Aug 12, 2002 |
| Grant date | Jun 28, 2005 |
| Priority date | — |
| Expiry date | Dec 26, 2023 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B7/0908
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
The present invention relates to method and apparatus of measuring axial vibration of a rotating disk. The present axial vibration measuring method selects a plurality of equally-spaced (45°˜120°-spaced) angular positions of a disk recording medium to conduct focusing operation at, conducts focusing operation at each selected position, measures focusing time from each start of the focusing operation to exactness in focus, and calculates axial vibration of the disk recording medium based on a deviation of the measured focusing times. The present method can measure exactly how much a rotating disk vibrates axially.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.