Glide-height disk-tester and method of operation
US7124625B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | May 17, 2005 |
| Grant date | Oct 24, 2006 |
| Priority date | — |
| Expiry date | May 17, 2025 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B5/6076
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A glide-height disk-tester operates with the test disk rotating at a predetermined constant rotational speed and uses a glide head with an electrically-resistive heater and a thermally-responsive protrusion pad located on its trailing end. The linear velocity of the disk relative to the slider maintains the slider at its nominal fly height, which is typically higher than any expected asperity. With no current applied to the heater, the protrusion pad is generally flush with the air-bearing surface of the slider. Increasing levels of current are applied to the heater, which causes movement of the protrusion pad toward the disk surface. When the pad contacts an asperity, the current level applied at the instant of asperity contact is recorded. The applied current level can be correlated to the glide height from a previous calibration process using a calibration disk with known calibration bump heights.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.