Method and apparatus for recording, reproducing and overwriting

Dynamic information storage or retrieval – Storage or retrieval by simultaneous application of diverse... – Magnetic field and light beam

Patent

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

360 59, G11B 1304, G11B 1112

Patent

active

055026923

ABSTRACT:
There are provided magnetooptic recording and reproducing method and apparatus of the Curie point writing type in which recording information can be read out by using a magnetic Kerr effect and the overwriting can be performed. At a position away from a laser irradiating section of a magnetooptic recording disk having first to third magnetic layers, there is applied a predetermined magnetic field which can magnetize the third magnetic layer in a uniform perpendicular direction and can magnetize the second magnetic layer in a uniform in-surface direction. Then, a recording bias magnetic field is applied to the laser irradiating section of the disk and a laser beam of a power such as to raise the temperature of the disk to a value near the Curie point of the first magnetic layer is simultaneously irradiated in accordance with a recording signal, thereby orienting the magnetizing direction of the first magnetic layer to a stable direction for the third magnetic layer without changing the magnetizing direction thereof. Or, a recording bias magnetic field is applied to the laser irradiating section of the disk and only a laser power so as to raise the temperature of the disk to a value near the Curie point of the third magnetic layer is simultaneously irradiated, thereby reversing the magnetizing direction of the third magnetic layer and magnetizing the first magnetic layer to a stable direction for the third magnetic layer.

REFERENCES:
patent: 4059828 (1977-11-01), Kobayashi et al.
patent: 4771347 (1988-09-01), Horimai et al.
patent: 4908809 (1990-03-01), Tadokoro et al.
patent: 4955007 (1990-09-01), Aratani et al.
Electronics, "Simple Nikon Technique permits erase and write in one pass", Electronics/Apr. 16, 1987, p. 33.

LandOfFree

Say what you really think

Search LandOfFree.com for the USA inventors and patents. Rate them and share your experience with other people.

Rating

Method and apparatus for recording, reproducing and overwriting does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Method and apparatus for recording, reproducing and overwriting , we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and apparatus for recording, reproducing and overwriting will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFUS-PAI-O-921415

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.