Magneto-optic information recording system
US4550346A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 14, 1983 |
| Grant date | Oct 29, 1985 |
| Priority date | — |
| Expiry date | Apr 14, 2003 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04N5/7805
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A magneto-optic information recording system for recording colorplexed composite video information on a magneto-optic information storage medium having a normal magnetization film, comprising means for emitting a recording laser beam to irradiate the normal magnetization film in the presence of a bias magnetic field; a field induction coil to induce the bias magnetic field; a low-pass filter for extracting a luminance signal component from the composite video information; a modulator to modulate the laser beam in accordance with the signal component extracted by the low-pass filter; a band-pass filter for extracting a carrier chrominance signal component from the composite video information; a frequency converter for converting the carrier chrominance signal component into a signal with a predetermined frequency lower than the frequency of the color subcarrier; and field control means responsive to the frequency-converted chrominance signal component and operative to vary the bias magnetic field in accordance with the frequency-converted chrominance signal component while the normal magnetization film is being irradiated with the modulated recording beam of light.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.