Multi-impact thermal asperity sensor head
US5825181A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 1, 1997 |
| Grant date | Oct 20, 1998 |
| Priority date | — |
| Expiry date | Apr 1, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B5/4886
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An asperity height sensing head and method of using the same are disclosed. The head includes multiple magnetoresistive (MR) sensors carried by a first rail of a slider adjacent to the air bearing surface (ABS) and positioned a distance L.sub.p from each other. Asperity height estimating circuitry coupled to each of the multiple MR sensors detects a number N of the MR sensors which exhibit a change in resistance as a result of contact between the ABS and a first asperity on the surface of the disc. The asperity height estimating circuitry estimates the height H.sub.A of the first asperity as a function of the number N, as a function of the pitch angle .theta..sub.p , and as a function of the distance L.sub.p.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.