Rotating recorder with dual encoder arrangement having eccentricity compensation
US7298678B2 · kind B2 · utility
2Cited by
1References
19Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Aug 19, 2004 |
| Grant date | Nov 20, 2007 |
| Priority date | — |
| Expiry date | Apr 6, 2026 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B5/82
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A rotating recording device, such as an electron beam recorder, is provided with a dual encoder arrangement. A first encoder is employed as a spindle motor controller and located at a first end of a spindle. A second encoder is mounted at a turntable adjacent to a recording surface and used as a position, velocity or clock source for recording the pattern on the substrate. Eccentricity of the mounting of the second encoder is measured against the more accurately mounted spindle control encoder and compensated by a digital clock generating system using a digital phase locked loop.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.