Embedded servo patterning methods and apparatus
US6865042B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 13, 2002 |
| Grant date | Mar 8, 2005 |
| Priority date | — |
| Expiry date | Jun 7, 2023 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B5/5965
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
The present invention involves a recordable disk having a first plurality of S1 servo sample wedges in a first servo zone at an outermost position on the disk, a second plurality of S2 servo sample wedges in a second servo zone which is radially adjacent the first servo zone, and a third plurality of S3 servo sample wedges in a third servo zone which is radially adjacent the second servo zone. The S1 servo sample wedges of the first plurality are equally spaced apart circumferentially around the disk by a first angle θ1, the S2 servo sample wedges of the second plurality are equally spaced apart circumferentially around the disk by a second angle θ2=θ1*N1, and the S3 servo sample wedges of the third plurality are equally spaced apart circumferentially around the disk by a third angle θ3=θ2*N2. Advantageously, S2=S1/N1 and S3=S2/N2, the S2 servo sample wedges of the second plurality are in radial alignment with every N1th wedge of the S1 servo sample wedges of the first plurality, and the S3 servo sample wedges of the third plurality are in radial alignment with every N2th wedge of the S2 servo sample wedges of the second plurality. The number of servo samples are increased nearer t…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.