Patent EP0126596A2 successfully refreshed from Google Patents.
EP0126596A2
Expired / Lapsed
EP
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Magneto-optic recording apparatus
Assignee: Xerox Corp
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Filing: 1984-05-11
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Granted: —
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Expires: 2004-05-11
Abstract
Abstract A writing, erasing and readout system for a magneto-optic record medium capable of achieving switching rates approaching the laser pulse rate, including at least two diode lasers (12, 14) operating through a single optical path and cooperating with bi-polar magnetic field producing means (50) located adjacent to and on the opposite side of the magneto-optic medium (54).
Inventors
- 👤 Connell G. A. Neville
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-03 22:37
CPC Classifications
G; G11; G11B; G11B5/00; G11B5/02; G11B5/024; G11B11/00; G11B11/10; G11B11/105; G11B11/10502; G11B11/10504; G11B11/10517; G11B11/10532; G11B11/10534; G11B11/10536; G11B11/1055
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
119 words
A magneto-optic recording apparatus for providing information input to a magneto-optic record medium having a number of tracks, including at least two iasers,(12, 14); means (22, 24) for selectively and independently addressing each of said lasers; and an optical system (28, 30, 34) interposed between the lasers and the record medium (32) for focusing the laser beams on at least one track of said medium, characterised by a magnet, located on the side of said medium remote from the optical system, including spaced pole pieces of opposite polarity positioned adjacent said medium, with one of the lasers being associated with one of said pole pieces, and another of the lasers being associated with the other of said pole pieces.
Claim 2
Dependent Claim
119 words
A magneto-optic recording apparatus for providing information input to a magneto-optic record medium having a number of tracks, including at least two iasers,(12, 14); means (22, 24) for selectively and independently addressing each of said lasers; and an optical system (28, 30, 34) interposed between the lasers and the record medium (32) for focusing the laser beams on at least one track of said medium, characterised by a magnet, located on the side of said medium remote from the optical system, including spaced pole pieces of opposite polarity positioned adjacent said medium, with one of the lasers being associated with one of said pole pieces, and another of the lasers being associated with the other of said pole pieces.
Claim 3
Dependent Claim
129 words
The magneto-optic recording apparatus as claimed in claim 1, characterized in that laser addressing means may be operated at a first state for driving a selected one of said lasers at a first energy level, wherein the optical energy output of said energized laser is sufficient to heat an addressed domain of said medium for allowing its related magnetic pole piece to affect the magnetization state of said domain, and in that the addressing means may be operated at a second state for driving a selected one of said lasers at a second energy level, wherein the optical energy output of said energized laser is insufficient to heat an addressed domain of said medium for allowing its related magnetic pole piece to affect the magnetization state of said domain.
Claim 4
Dependent Claim
48 words
The apparatus as claimed in claim 1 or 2, characterized in that said optical system means includes deflection means for redirecting a laser beam reflected from said medium, and detection means for sensing characteristics of said laser beam, whereby the information recorded on said medium may be read.
Claim 5
Independent Claim
47 words
The apparatus as claimed in any preceding claim, characterized in that said laser means comprises a solid state laser array including a first laser and a second laser, wherein each of said first and second lasers are associated with one of said opposite polarity magnetic pole pieces.
Claim 6
Independent Claim
50 words
The apparatus as claimed in any of claims 1-3, characterized in that said lasers comprise a solid state laser array including a first laser, a second laser and a third laser, wherein each of said first and second lasers are associated with one of said opposite polarity magnetic pole pieces.
Claim 7
Dependent Claim
23 words
The apparatus as claimed in claim 5, characterized in that said third laser is positioned between said first laser and said second laser.
Claim 8
Independent Claim
37 words
The apparatus as claimed in any preceding claim, characterized in that said record medium is a rotatable disk, and said magnet extends from the innermost track to the outermost track of said disk in a substantially-radial direction.
Claim 9
Independent Claim
51 words
The apparatus as claimed in any of claims 1-6, characterized in that said record medium is a rotatable disk, and said magnet extends over less than all the tracks in a substantially-radial direction, and further including means for moving said magnet in a substantially-radial direction between said innermost and outermost tracks.
Claim 10
Independent Claim
66 words
The apparatus as claimed in any preceding claim, wherein one pole piece is used with its associated laser during writing for creating areas on said medium magnetised in a data-bearing direction, and the other pole piece is used with its associated laser during erasing for creating areas on said medium magnetised in a neutral direction, and wherein the neutral areas are larger than the data areas.
Claim 11
Dependent Claim
39 words
The apparatus as claimed in claim 9, characterized in that the neutral domains are caused to be larger than the data domains by providing a higher magnetic field from said other pole piece than from said one pole piece.
References Cited (Backward Citations)
No citation records indexed.
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