Method and apparatus for determining systematic errors
US5901003A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 8, 1996 |
| Grant date | May 4, 1999 |
| Priority date | — |
| Expiry date | Apr 8, 2016 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B21/106
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Improvements in placement of timing patterns in self servo writing include correcting for random and systematic errors due to geometric effects. In a disk drive having a recording head with separate read and write elements, a method for determining separation between the elements and for correcting for such errors as a function of skew angle between the head and the disk. Errors resulting from misalignment and non-parallelism of the elements as well as misalignment of the head on it its actuator are also detected and corrected. Errors due to changes in rotational velocity of the disk and misplacement of timing patterns with respect to adjacent timing patterns are detected and corrected. In general, a single revolution process may be used to both write and detect random errors on each track and corrected on subsequent tracks.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.