Read-only magnetic recording media
US4746580A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 6, 1986 |
| Grant date | May 24, 1988 |
| Priority date | — |
| Expiry date | Mar 6, 2006 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31681
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A method of making read-only magnetic recording media by the use of photolithographic/photoresist techniques, and the vacuum deposition of discrete bits of a high coercivity metal, followed by magnetization of said metal. A nonmagnetic substrate is covered by a layer of photoresist and a layer of high coercivity magnetic material. Selective light-pattern exposure of the resist, followed by layer-removal-procedures, cause the substrate to be covered by islands of hard magnetic material, in the pattern of a desired data track. The substrate is then subjected to the influence of a steady-state magnetic field in order to convert the metal islands into a read-only data pattern which can be read by a magnetic head. A floppy disk of this type is used to stress-test the head placement of floppy disk drives.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.