US5034933A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Magneto-optical recording apparatus
Assignee: Sony Corp
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Filing: 1990-02-20
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Granted: 1991-07-23
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Expires: 2010-02-20
Abstract
Abstract A magneto-optical disc recording apparatus arranged such that the magneto-optical disc is recorded by irradiating the magneto-optical disc with a recording light beam from an optical pickup head device under the condition that the optical pickup head device is applied with an external magnetic field by external magnetic field generating means. In this magneto-optical disc recording apparatus, a spacer sheet is located on the magneto-optical disc, whereby the external magnetic field is applied to the magneto-optical disc under the condition that the external magnetic field generating means is brought in contact with the spacer sheet.
Inventors
- 👤 Hirotoshi Fujisawa
- 👤 Takashi Ohmori
- 👤 Ryo Ando
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 15:27
CPC Classifications
G; G11; G11B; G11B7/00; G11B7/08; G11B17/00; G11B17/02; G11B17/04; G11B17/041; G11B17/044; G11B17/046; G11B11/00; G11B11/10; G11B11/105; G11B11/1055; G11B11/10556; G11B11/10558; G11B11/10576; G11B17/022; G11B17/028; G11B17/032; G11B17/05; G11B17/053; G11B17/054; G11B17/32
Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
81 words
In a magneto-optical disc recording apparatus of the type in which a magneto-optical disc is recorded by irradiating the magneto-optical disc with a recording light from a beam optical pickup head device under the condition that the magneto-optical disc has applied to it an external magnetic field by external magnetic field generating means, the improvement comprising a spacer sheet to be mounted on the magneto-optical disc wherein the external magnetic field generating means is brought in contact with the spacer sheet.
Claim 2
Dependent Claim
81 words
In a magneto-optical disc recording apparatus of the type in which a magneto-optical disc is recorded by irradiating the magneto-optical disc with a recording light from a beam optical pickup head device under the condition that the magneto-optical disc has applied to it an external magnetic field by external magnetic field generating means, the improvement comprising a spacer sheet to be mounted on the magneto-optical disc wherein the external magnetic field generating means is brought in contact with the spacer sheet.
Claim 3
Dependent Claim
40 words
A magneto-optical disc recording apparatus according to claim 1, wherein the spacer sheet is opposed to the magneto-optical disc on its surface opposite to its surface on which the recording light beam from the optical pickup head device becomes incident.
Claim 4
Dependent Claim
44 words
A magneto-optical disc recording apparatus according to claim 1, further comprising spring-biasing means wherein the external magnetic field generating means is spring-biased by the spring-biasing means in the direction in which the external magnetic field generating means comes in contact with the spacer sheet.
Claim 5
Dependent Claim
25 words
A magneto-optical disc recording apparatus according to claim 1, wherein the spacer sheet is formed of a material which has an excellent smooth surface property.
Claim 6
Dependent Claim
48 words
A magneto-optical disc recording apparatus according to claim 1, wherein the spacer sheet is made of a flexible material so as to become closely conformable to the magneto-optical disc surface opposite to its surface on which the recording light beam from the optical pickup head device becomes incident.
Claim 7
Dependent Claim
56 words
A magneto-optical disc recording apparatus according to claim 1, further comprising rotary holding means for rotating the magneto-optical disc under the condition that the magneto-optical disc is held by the rotary holding means, wherein when the magneto-optical disc is held by the rotary holding means, the spacer sheet is unitarily rotated together with the magneto-optical disc.
Claim 8
Dependent Claim
33 words
A magneto-optical disc recording apparatus according to claim 6, wherein the rotary holding means is comprised of a chucking plate and a turntable, and the spacer sheet is secured to the chucking plate.
Claim 9
Dependent Claim
46 words
A magneto-optical disc recording apparatus according to claim 6, wherein the rotary holding means includes releasing means for releasing the spacer sheet being closely conformed to the magneto-optical disc when the rotary holding means is changed from the magneto-optical disc held state to a non-held state.
Claim 10
Dependent Claim
51 words
A magneto-optical disc recording apparatus according to claim 8, wherein the releasing means includes a movable member for moving the magneto-optical disc so that the magneto-optical disc is spaced apart from the spacer sheet when the rotary holding means is changed from the magneto-optical disc held state to the non-held state.
Claim 11
Dependent Claim
30 words
A magneto-optical disc recording apparatus according to claim 1, further comprising protecting means for protecting the spacer sheet when the magneto-optical disc is inserted into and/or ejected from the apparatus.
Claim 12
Dependent Claim
40 words
A magneto-optical disc recording apparatus according to claim 10, wherein the protecting means is a disc tray for preventing the magneto-optical disc from contacting with the spacer sheet when the magneto-optical disc is loaded onto and/or ejected from the apparatus.
Claim 13
Dependent Claim
151 words
A magneto-optical disc recording apparatus comprising: an apparatus body including a optical pickup head device for irradiating a magneto-optical disc with a recording light beam under the condition that the magneto-optical disc has an external magnetic field applied to it and rotary drive means for rotating the magneto-optical disc; and a lid including external magnetic field generating means for applying an external magnetic field to the magneto-optical disc, holding means for holding the magneto-optical disc together with the rotary drive means so that the magneto-optical disc can be rotated, and a spacer sheet mounted on the magneto-optical disc for controlling the position of the external magnetic field generating means so that a distance between the external magnetic field generating means and the magneto-optical disc becomes constant, the lid being rotatably attached to the apparatus body, and wherein the external magnetic field generating means is brought in contact with the spacer sheet.
Claim 14
Dependent Claim
151 words
A magneto-optical disc recording apparatus comprising: an apparatus body including a optical pickup head device for irradiating a magneto-optical disc with a recording light beam under the condition that the magneto-optical disc has an external magnetic field applied to it and rotary drive means for rotating the magneto-optical disc; and a lid including external magnetic field generating means for applying an external magnetic field to the magneto-optical disc, holding means for holding the magneto-optical disc together with the rotary drive means so that the magneto-optical disc can be rotated, and a spacer sheet mounted on the magneto-optical disc for controlling the position of the external magnetic field generating means so that a distance between the external magnetic field generating means and the magneto-optical disc becomes constant, the lid being rotatably attached to the apparatus body, and wherein the external magnetic field generating means is brought in contact with the spacer sheet.
Claim 15
Dependent Claim
39 words
A magneto-optical disc recording apparatus according to claim 12, wherein the spacer sheet is located on the magneto-optical disc at its surface opposite to its surface on which a recording light from the optical pickup head device becomes incident.
Claim 16
Dependent Claim
44 words
A magneto-optical disc recording apparatus according to claim 12, further comprising spring-biasing means wherein the external magnetic field generating means is spring-biased by the spring-biasing means in such a direction that the external magnetic field generating means comes in contact with the spacer sheet.
Claim 17
Dependent Claim
25 words
A magneto-optical disc recording apparatus according to claim 12, wherein the spacer sheet is formed of a material which has an excellent surface smooth property.
Claim 18
Dependent Claim
32 words
A magneto-optical disc recording apparatus according to claim 12, wherein the spacer sheet is formed of a flexible material so that the spacer sheet can be closely stuck to the magneto-optical disc.
Claim 19
Dependent Claim
35 words
A magneto-optical disc recording apparatus according to claim 12, wherein the spacer sheet is unitarily rotated with the magneto-optical disc when the magneto-optical disc is held by the rotary drive means and the holding means.
Claim 20
Dependent Claim
19 words
A magneto-optical disc recording apparatus according to claim 17, wherein the spacer sheet is secured to the holding means.
Claim 21
Dependent Claim
43 words
A magneto-optical disc recording apparatus according to claim 12, wherein the holding means includes releasing means for releasing the spacer sheet closely stuck to the magneto-optical disc when the holding means is changed from the magneto-optical disc held state to a non-held state.
Claim 22
Dependent Claim
50 words
A magneto-optical disc recording apparatus according to claim 19, wherein the releasing means includes a movable member for moving the magneto-optical disc such that the magneto-optical disc is spaced apart from the spacer sheet when the holding means is changed from the magneto-optical disc held state to the non-held state.
Claim 23
Dependent Claim
32 words
A magneto-optical disc recording apparatus according to claim 12, wherein the lid includes protecting means for protecting the spacer sheet when the magneto-optical disc is inserted into and/or ejected from the apparatus.
Claim 24
Dependent Claim
39 words
A magneto-optical disc recording apparatus according to claim 21, wherein the protecting means is a disc tray for preventing the magneto-optical disc from contacting the spacer sheet when the magneto-optical disc is inserted into and/or ejected from the apparatus.
Claim 25
Dependent Claim
119 words
A magneto-optical disc recording apparatus of the type in which a magneto-optical disc is recorded by irradiating one surface of the magneto-optical disc with a recording light from a beam optical pickup head device under the condition that the magneto-optical disc has applied to it an external magnetic field, wherein the improvement comprises: an external magnetic field generating means; a spacer sheet; means for conforming the spacer sheet onto a flat surface of the magneto-optical disc which is opposite to the recording light irradiated surface of the magneto-optical disc; and means for bringing the external magnetic field generating means in contact with the spacer sheet after the spacer sheet is conformed onto the flat surface of the magneto-optical disc.
Claim 26
Dependent Claim
119 words
A magneto-optical disc recording apparatus of the type in which a magneto-optical disc is recorded by irradiating one surface of the magneto-optical disc with a recording light from a beam optical pickup head device under the condition that the magneto-optical disc has applied to it an external magnetic field, wherein the improvement comprises: an external magnetic field generating means; a spacer sheet; means for conforming the spacer sheet onto a flat surface of the magneto-optical disc which is opposite to the recording light irradiated surface of the magneto-optical disc; and means for bringing the external magnetic field generating means in contact with the spacer sheet after the spacer sheet is conformed onto the flat surface of the magneto-optical disc.
Claim 27
Dependent Claim
23 words
A magneto-optical disc recording apparatus as recited in claim 23 wherein the spacer sheet is molded of a smooth, light-weight, non-magnetic, plastic material.
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) | 1994-07-22 | 1995-01-21 | 1995-07-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-07-22 | 1999-01-21 | 1999-07-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-07-22 | 2003-01-21 | 2003-07-23 | $7700.00 | Window Closed / Lapsed |