Method for magnetically recording digital video signals with specified ranges of the easy axis and the bias magnetic field
US5247397A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Oct 23, 1991 |
| Grant date | Sep 21, 1993 |
| Priority date | — |
| Expiry date | Oct 23, 2011 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N5/9261
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A magnetic recording transfer method for use with the combination of a mother magnetic recording medium and a copy magnetic recording medium of a metal-deposited thin film type each. The two media are overlaid so that the column inclination of one medium will be opposite in direction to that of the other medium. This method comprises the step of externally applying a biased magnetic field to the combination of the media in such a manner that magnetized recordings on the mother medium will be transferred to the copy medium. The easy axis of the mother medium is positioned at an angle of 20.degree..+-.15.degree. with respect to the in-plane direction of the medium. The biased magnetic field is applied to the mother medium at an angle of 110.degree..+-.15.degree. with respect to the in-plane direction of the medium. This makes it possible to enhance the efficiency in transferring magnetic recording of the mother medium, especially the recordings of short wave lengths, and to minimize demagnetization of the mother medium. Furthermore, the ratio of the coercive force H.sub.CM of the mother medium to the coercive force H.sub.CC of the copy medium (H.sub. CM /H.sub.CC) is set to at most 1…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.