Modulation of sidewalls of servo sectors of a magnetic disk and the resultant disk
US7161753B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 28, 2005 |
| Grant date | Jan 9, 2007 |
| Priority date | — |
| Expiry date | Jan 28, 2025 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B5/6011
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A discrete-track-recording (DTR) disk (also called “patterned” disk) has a sectored servo formed by modulation of its sidewalls in a predetermined manner, whereas sidewalls of data sectors are not modulated in this manner. Each servo sector has two side walls that are each respectively modulated in two different ways. Hence, a readback signal from a given servo sector contains components of each of the two different modulations, even in case of “DC” erase initiation. Therefore, the just-described modulated servo sectors eliminate servowriting. Moreover, data signals are read without filtering the modulation, because data sector sidewalls are not modulated.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.