Functional measurement of data head misregistration
US5233487A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 27, 1991 |
| Grant date | Aug 3, 1993 |
| Priority date | — |
| Expiry date | Jun 27, 2011 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2020/183
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
The present invention demonstrates a rotating media storage system which quickly measures and accurately compensates for thermal and mechanical errors in the position of the data detector with respect to the written data. This is accomplished by measuring the error rate of the written data as a function of the read offset of the detector. Error rates become increasingly large as the sensed noise to signal ratio becomes large. The present invention counts the number of errors detected in reading written data for various read offsets when the data storage system is initially activated. When the number of errors reaches a target rate, the read offset required to produce the target rate is saved. This procedure is performed on either side of the data track. The detector is then centered between the two offsets. During the operation of the storage system, thermal and mechanical errors are introduced into the detector position compensation means. The present invention compensates for this by periodically determining a new offset for each side of the data track. The new offset which corresponds to the target error rate is found by interpolating between measured offsets for error rates whi…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.