Structure to provide optical and capacitive contrast on magnetic recording disk
US4737877A · kind A · utility
34Cited by
6References
4Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | May 5, 1986 |
| Grant date | Apr 12, 1988 |
| Priority date | — |
| Expiry date | May 5, 2006 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG11B5/59677
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A magnetic recording disk is formed on a rigid aluminum substrate coated with a polymeric dielectric layer. A thin film metallic position-indicating track is applied to the upper surface of the dielectric layer. The dielectric material is coated with a magnetic recording medium. A thin film of aluminum forms the patterned capacitive and optically reflective track. The dielectric layer is composed of a very similar material to the matrix material in the magnetic recording medium. The disk can be flexible or floppy and it is not necessary to have the extra dielectric layer in such a case, where the substrate is a dielectric.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.