Magneto-optical recording apparatus and method including method for presetting optimum recording power of recording apparatus
AssigneeCanon Kabushiki Kaisha
InventorYasuyuki Miyaoka
Life of this patent
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Abstract
Disclosed herein is a testing process for recording for presetting optimum recording power for a domain wall displacement type magneto-optical medium, the process comprising the steps of: recording a first record pattern on an Nth track on the magneto-optical medium; separately recording a second record pattern on an (N−1)th track and an (N+1)th track adjacent to both sides of the Nth track with varied recording power; reproducing the Nth track to detect a change in the pulse width of a reproduction signal; detecting recording power, at which cross writing occurs, on the basis of the detected result; and presetting optimum recording power on the basis of the recording power at which cross writing occurs.
Claims9
A method for test recording and presetting optimum recording power for a domain wall displacement type magneto-optical medium, the method comprising the steps of:
- recording a first test record pattern on an Nth track on the magneto-optical medium;
- separately recording a second test record pattern on an (N−1)th track and an (N+1)th track adjacent to both sides of the Nth track with varied recording power;
- reproducing a signal on the Nth track and detecting a change in the pulse width of a reproduction signal while reproducing the signal on the Nth track;
- determining a recording power at which cross writing occurs on the Nth track, on the basis of the detected result in said signal reproducing and pulse width change detecting step;
- and
- presetting the optimum recording power on the basis of the recording power at which cross writing occurs, as determined in the recording power determining step.
A magneto-optical recording-reproducing apparatus for recording information on a domain wall displacement type magneto-optical medium, the apparatus comprising:
- a light source that emits a light beam;
- a recording circuit that records a first test record pattern on an Nth track on the medium and separately records a second test record pattern on an (N−1)th track and an (N+1)th track adjacent to both sides of the Nth track with varied recording power while controlling the light source;
- a reproduction circuit that detects the first test record pattern by means of the light beam so as to output a reproduction signal;
- a pulse width change detection circuit that detects a change in the pulse width of the reproduction signal;
- and
- a recording power determination circuit that determines a recording power at which cross writing occurs, on the basis of the detected result of said pulse width change detection circuit, and presets an optimum recording power of the recording circuit on the basis of the recording power determined by said recording power determination circuit.
Dependencies are inferred from the claim text.