Position demodulation apparatus and position demodulation method
US8553345B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 2, 2012 |
| Grant date | Oct 8, 2013 |
| Priority date | — |
| Expiry date | Apr 12, 2032 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B5/5547
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
According to one embodiment, a position demodulation method includes demodulating a first demodulation signal and a second demodulation signal having a phase difference of 90 degrees to the first demodulation signal based on a read-out signal obtained by reading out a servo pattern recorded on a medium by the head for positioning of a head with respect to the medium; correcting the first and second demodulation signals in which, when a trace of a Lissajous figure is drawn representing the first and second demodulation signals as values on coordinate axes different from each other on a plane, a ratio of respective lengths between intersections of the trace intersecting with two axes orthogonal at an origin of the plane is kept constant; and demodulating a positional signal for determining a position of the head based on the first and second demodulation signals after being corrected at the correcting.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.