Magnetic disk stack having laser-bump identifiers on magnetic disks
US6118632A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 12, 1997 |
| Grant date | Sep 12, 2000 |
| Priority date | — |
| Expiry date | Feb 12, 2017 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B2220/65
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A magnetic disk with nonmagnetic information encoded under, in or above the magnetic layer of the disk is described along with the disk drive using the magnetic disks. The information may be stored as a series of laser-written marks (e.g., bumps, oxidized spots or spots with altered reflectivity) upon the surface(s) of each disk of the disk stack. The set of marks may be a series of laser bumps which serve a dual purpose as a landing zone or contact start/stop (CSS) zone for the slider and as encoded identifying information. During the manufacturing process for disk drives containing the disks, each disk's identifier can be read using outboard equipment such as an HRF tester or by means contained in the drive itself. Each disk identifier can then be stored magnetically in a special region of the hard disk reserved for use by the drive and/or within the flash memory of the hard drive. The drive can then communicate the identifier(s) to a host computer using the conventional communication hardware and firmware. In this way selected information such as the origin, batch number, date of manufacture, serial number, etc. of any disk can be obtained when needed as, for example, as part of…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.