Tunable contact detection sensitivity to directly measure clearance of protrusions in magnetic recording heads
US9595281B2 · kind B2 · utility
4Cited by
7References
20Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Aug 11, 2015 |
| Grant date | Mar 14, 2017 |
| Priority date | — |
| Expiry date | Aug 11, 2035 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2005/0021
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
Embodiments disclosed herein generally relate to contact at the disk by the recording head in a hard disk drive. In one embodiment, a direct current is applied to an element in a HAMR head. An alternating current is then applied to the element over top of the direct current to cause the HAMR head to dither. By monitoring the head signal at the dither frequency, a touchdown or contact of a NFT on a disk may be detected based upon variations in the produced signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.