Magnetic disk device and method of recording/retrieving information
US5109311A · kind A · utility
14Cited by
4References
38Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | May 6, 1991 |
| Grant date | Apr 28, 1992 |
| Priority date | — |
| Expiry date | May 6, 2011 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B5/82
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
This invention provides a magnetic disk device having a total memory capacity of 30 giga bytes or more, or more desirably 30.about.40 giga bytes. The magnetic disk used in this magnetic disk device has a plane record density of 45.about.80 mega bits per square inch. The thin film magnetic head has a pole thickness (P.sub.T), a magnetic flux density (B.sub.s), a magnetic gap depth (G.sub.d) and a record wavelenth (.lambda.) which satisfy the formula EQU G.sub.d .ltoreq.0.13 P.sub.T B.sub.s (.lambda.+4.3)-2.1. The magnetic disk rotation means rotate the magnetic disk at a speed of 24 m per second or more.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.