Capacitive measurement and control of the fly height of a recording slider
US4931887A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 1, 1988 |
| Grant date | Jun 5, 1990 |
| Priority date | — |
| Expiry date | Feb 1, 2008 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B5/58
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A device and method for capacitive measurement and control of the fly height of a recording slider. A recording slider is vertically spaced from a rotating disk surface by an "air bearing". The disk has a first electrically conductive pattern at its surface. The first pattern has an edge with a length extending, for example, radially. The recording slider has one or more electrically conductive rails extending transverse to the radial pattern on the rotating disk. As the disk rotates, the edge of the pattern on the disk scans across the rail of the slider. By measuring the electrical capacitance between the slider and the pattern on the disk, and by processing the electrical capacitance measurement signal, a vertical spacing signal proportional to the vertical spacing between the disk and the slider can be obtained.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.