EP0220023A2
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EP
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Optical magnetic memory device
Assignee: Sharp Corp
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Filing: 1986-10-08
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Granted: —
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Expires: 2006-10-08
Abstract
Abstract The device comprises an optical magnetic recording medium having recording magnetic film (42) at least on one side and initialized in a certain direction in advance, a recording section (40, 41) for recording data in such a manner that data-recorded portions and non-recorded portions are alternately formed, and a reproducing section for reproducing data from the recording medium by detecting the interval between the recorded or non-recorded portions. The reproducing section comprises a detector (3) for detecting positive and negative peaks of signals reproduced from the recorded or non-recorded portion and a selector (30) for selecting either of the detection outputs from the detector according to a control signal (32).
Inventors
- 👤 Hiroshi Fuji
- 👤 Shigemi Maeda
- 👤 Takeshi Yamaguchi
- 👤 Toshihisa Daiya-Heights Deguchi
- 👤 Shozou Kobayashi
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-09 06:42
CPC Classifications
G; G11; G11B; G11B11/00; G11B11/10; G11B11/105; G11B11/10502; G11B11/10515; G11B11/10504; G11B11/10506; G11B11/10595; G11B11/10597
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
109 words
An optical magnetic memory device comprising: an optical magnetic recording medium having, at least on one side, recording magnetic film initialized in a certain direction; means for recording information so that data-recorded portions and non-recorded portions are alternately formed on said magnetic film of said optical magnetic recording medium; means for reproducing information from said recording medium by detecting the intervals between said recorded portions or non-recorded portions; and said reproducing means containing means for detecting positive and negative peaks of a signal reproduced from said recorded or non-recorded portion, and means for selecting either of the detection signal outputs from said detecting means according to a control signal.
Claim 2
Dependent Claim
109 words
An optical magnetic memory device comprising: an optical magnetic recording medium having, at least on one side, recording magnetic film initialized in a certain direction; means for recording information so that data-recorded portions and non-recorded portions are alternately formed on said magnetic film of said optical magnetic recording medium; means for reproducing information from said recording medium by detecting the intervals between said recorded portions or non-recorded portions; and said reproducing means containing means for detecting positive and negative peaks of a signal reproduced from said recorded or non-recorded portion, and means for selecting either of the detection signal outputs from said detecting means according to a control signal.
Claim 3
Dependent Claim
86 words
An optical magnetic memory device which contains an optical magnetic medium having recording film on both sides and initialized in one direction in advance and which records data in such a manner as to allow detection of the interval between recorded marks, being characterized in that said memory device includes means for detecting positive and negative peaks of reproduced signals and that data is reproduced by selecting one of the outputs from said detecting means according to a control signal such as recorded side identification signal.
Claim 4
Dependent Claim
86 words
An optical magnetic memory device which contains an optical magnetic medium having recording film on both sides and initialized in one direction in advance and which records data in such a manner as to allow detection of the interval between recorded marks, being characterized in that said memory device includes means for detecting positive and negative peaks of reproduced signals and that data is reproduced by selecting one of the outputs from said detecting means according to a control signal such as recorded side identification signal.
Claim 5
Dependent Claim
46 words
An optical memory device for recording, reproducing or erasing data by irradiating optical data recording medium with laser beam spot, wherein data is recorded in such a manner as to allow detection of the interval between marks for reproduction, and wherein said marks are non-recorded portions.
Claim 6
Dependent Claim
46 words
An optical memory device for recording, reproducing or erasing data by irradiating optical data recording medium with laser beam spot, wherein data is recorded in such a manner as to allow detection of the interval between marks for reproduction, and wherein said marks are non-recorded portions.
Claim 7
Dependent Claim
19 words
The optical memory device of claim 3, wherein data is reproduced by detecting the interval between said non-recorded portions.
Claim 8
Independent Claim
113 words
A device for reproducing data recorded on an optical magnetic medium of which both sides are capable of retaining recorded data in the form of spaced zones magnetized in a direction different to the direction of initial magnetization, said direction of initial magnetization being the same for both sides, the device including reproducing means for producing a data signal using reproducing radiation directed on to either side of the medium, detection means for detecting positive pulses in the data signal for one side and negative pulses in the data signal for the other side, and selection means for causing a reproduction output to be produced selectively using the positive or negative pulse detection.
Claim 9
Independent Claim
113 words
A device for reproducing data recorded on an optical magnetic medium of which both sides are capable of retaining recorded data in the form of spaced zones magnetized in a direction different to the direction of initial magnetization, said direction of initial magnetization being the same for both sides, the device including reproducing means for producing a data signal using reproducing radiation directed on to either side of the medium, detection means for detecting positive pulses in the data signal for one side and negative pulses in the data signal for the other side, and selection means for causing a reproduction output to be produced selectively using the positive or negative pulse detection.
Claim 10
Dependent Claim
40 words
A device according to claim 5 wherein selection between use of the positive pulse detection and use of the negative pulse detection is made according to the side of the medium from which data is being or to be reproduced.
References Cited (Backward Citations)
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