Method for determining an outer diameter rolloff in a process for making magnetic disks
US5497085A · kind A · utility
23Cited by
2References
16Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Dec 19, 1994 |
| Grant date | Mar 5, 1996 |
| Priority date | — |
| Expiry date | Dec 19, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B5/6005
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A method is shown for testing a magnetic disk to be used in a disk drive. The method includes the steps of measuring a height profile of an outer radial edge of the disk, using the profile to determine a slope value for each of a pair of radial segments of the disk, calculating a difference value between the slope values of the pair, comparing the difference value to a preselected threshold difference value and indicating when the difference value is equal to or less than the threshold difference value. The threshold value indicates an outer most diameter of the disk where fly height operation for a head is still stable.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.