Magnetic media with randomly positioned texturing features
US6404590B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 6, 2000 |
| Grant date | Jun 11, 2002 |
| Priority date | — |
| Expiry date | Jan 6, 2020 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B17/32
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A magnetic data storage medium includes a dedicated transducing head contact zone for engaging an air bearing slider, primarily when the disk is stationary. The contact zone is textured with an irregular sequence of spaced apart nodules forming a substantially circumferential, spiral path. The spiral path includes multiple terms that define a uniform radial pitch. The circumferential pitch is irregular, more preferably determined according to pseudo-random function in which the actual spacing intervals vary about a nominal interval, over a range comparable to, but generally less than, the interval. The pseudo-random array can be formed by a texturing process that includes directing a focused laser beam onto the contact zone. The disk is rotated to maintain a constant circumferential speed relative to the laser, and also is translated radially to provide the desired radial pitch. The laser is operated in a continuous wave mode, with an acousto-optic modulator between the laser and disk operated to provide a pseudo-random variance in time intervals between successive laser exposures.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.