US4998231A
Expired / Lapsed
US
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Magneto-optical disk recording apparatus
Assignee: Sony Corp
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Filing: 1989-12-08
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Granted: 1991-03-05
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Expires: 2009-12-08
Abstract
Abstract A magneto-optical disk recording apparatus sequentially pulse-drive a plurality of semiconductor laser elements in a time-divisional manner so that spots of light are sequentially formed along a plurality of recording tracks of a magneto-optical disk with clock information recorded in advance along a plurality of recording tracks thereon. A magnetic modulating signal is generated by combining pieces of information desired to be recorded along the plurality of recording tracks so that a modulating magnetic field whose polarity is reversed in accordance with the magnetic modulating signal is applied to the plurality of recording tracks by means of a magnetic head.
Inventors
- 👤 Tetsu Watanabe
- 👤 Hiroshi Ogawa
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 14:30
CPC Classifications
G; G11; G11B; G11B11/00; G11B11/10; G11B11/105; G11B11/10502; G11B11/10517; G11B11/10519; G11B11/10504; G11B11/1051; G11B11/10513
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
104 words
A magneto-optical disk recording apparatus comprising: a plurality of laser beam sources; an optical system for focusing light beams for said laser beam sources on a plurality of recording tracks of a magneto-optical disk; driving means for sequentially pulse-driving said laser beam sources in a time-divisional manner; magnetic modulating signal generating means for generating a magnetic modulating signal by combining data desired to be recorded along said plurality of recording tracks in said time-divisional manner; and external magnetic field generating means for applying to said plurality of recording tracks a modulating magnetic field whose polarity is reversed in accordance with said magnetic modulated signal.
Claim 2
Dependent Claim
104 words
A magneto-optical disk recording apparatus comprising: a plurality of laser beam sources; an optical system for focusing light beams for said laser beam sources on a plurality of recording tracks of a magneto-optical disk; driving means for sequentially pulse-driving said laser beam sources in a time-divisional manner; magnetic modulating signal generating means for generating a magnetic modulating signal by combining data desired to be recorded along said plurality of recording tracks in said time-divisional manner; and external magnetic field generating means for applying to said plurality of recording tracks a modulating magnetic field whose polarity is reversed in accordance with said magnetic modulated signal.
Claim 3
Dependent Claim
28 words
A magneto-optical disk recording apparatus according to claim 1 wherein at least one of said recording tracks is provided with clock information recorded along the same in advance.
Claim 4
Dependent Claim
54 words
A magneto-optical disk recording apparatus according to claim 1 further comprising detection means receiving beams reflected from said magneto-optical disk and generating a clock information signal, and reference clock generating means responsive to said clock information signal for generating a reference clock for timing said driving means and said magnetic modulating signal generating means.
Claim 5
Dependent Claim
72 words
A magneto-optical disk recording apparatus according to claim 2 wherein said reference clock has a clock period and said magnetic modulating signal generating means produces a plurality of data to be recorded in synchronism with said reference clock, sequentially and cyclically combines said plurality of data to be recorded, each thereof being allotted a predetermined fraction of the clock period, and delivers the combined data to said external magnetic field generating means.
Claim 6
Dependent Claim
64 words
A magnetic-optical disk recording apparatus according to claim 2 wherein said magnetic modulating signal generating means produces a plurality of data to be recorded in synchronism with said reference clock, sequentially and cyclically combines said plurality of data to be recorded, each thereof being allotted a different one-third of the clock period, and delivers the combined data to said external magnetic field generating means.
Claim 7
Dependent Claim
26 words
A magneto-optical disk recording apparatus according to claim 2 wherein said driving means generates a plurality of driving pulses for respectively driving said laser beam sources.
Claim 8
Dependent Claim
61 words
A magneto-optical disk recording apparatus according to claim 6 wherein said reference clock has a clock period and said driving means generates a driving pulse serving as a reference pulse rising when said reference clock rises and plurality of additional driving pulses rising so as to sequentially follow said reference pulse with respective delays of predetermined fractions of the clock period.
Claim 9
Dependent Claim
66 words
A magneto-optical disk recording apparatus according to claim 6 wherein said reference clock has a clock period and said driving means is adapted to generate a first driving pulse rising when said reference clock rises and a second driving pulse and a third driving pulse respectively rising so as to sequentially follow said first driving pulse with delays of one-third and two-thirds of the clock period.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-03-04 | 1994-09-03 | 1995-03-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-03-04 | 1998-09-03 | 1999-03-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-03-04 | 2002-09-03 | 2003-03-05 | $7700.00 | Window Closed / Lapsed |