Title:
MAGNETO-OPTICAL INFORMATION RECORDER
Document Type and Number:
Japanese Patent JP2539585
Kind Code:
B2
Abstract:
PURPOSE: To rapidly and stably record and erase information by previously impressing external magnetic field before an optical pulse for recording and erasing radiates a recording medium and interrupting the external magnetic field after the irradiation of the optical pulse is ended.
CONSTITUTION: At the time of recording, a coil driving current is impressed to an electromagnetic coil 10 by a coil driving circuit 16 to generate recording magnetic field. The required information is recorded stably on a disk 1 by impressing a laser driving pulse to a modulation circuit 11 after the recording magnetic field arrives at a normal state and modulating a semiconductor laser 5. When the movement to an erasure mode is instructed, by the circuit 16, the coil driving current in the direction opposite to the recording mode time is made to flow through the coil 10. In such a case, only a sector formed before by one sector or more than a track to be erased is moved to the erasure mode, When the laser driving pulse is impressed to the circuit 11 after the erasure magnetic field arrives at the normal state and the laser 5 is modulated, the information is surely erased.
Inventors:
SAITO ATSUSHI
OSHIMA MASAHIRO
MAEDA TAKESHI
KATO TAKESHI
OSHIMA MASAHIRO
MAEDA TAKESHI
KATO TAKESHI
Application Number:
JP25029793A
Publication Date:
October 02, 1996
Filing Date:
October 06, 1993
Export Citation:
Assignee:
HITACHI LTD
International Classes:
G11B11/10; G11B11/105; (IPC1-7): G11B11/10; G11B11/10
Domestic Patent References:
| JPS61950A | ||||
| JPH0619863A | ||||
| JPS59120000A |
Attorney, Agent or Firm:
Ogawa Katsuo