Claims
- 1. A magneto-optic recording medium, comprising:
- a transparent substrate;
- a first dielectric layer provided above said transparent substrate;
- a magnetic layer provided above said first dielectric layer;
- a second dielectric layer provided above said magnetic layer; and
- a reflecting layer provided above said second dielectric layer,
- said magnetic layer being made of a composition modulated material which is modulated in a direction in which a thickness thereof is taken so as to have at least a first composition on a light incident side of said magnetic layer, and a second composition on an opposite side from the light incident side, wherein said first and second compositions are different,
- said second dielectric layer and said reflecting layer causing an enhancement effect which is defined as an overlap of a Kerr rotation angle of light at a surface on the light incident side of said magnetic layer and a Faraday rotation angle of light which is transmitted through said magnetic layer and reflected by said reflecting layer.
- 2. The magneto-optic recording medium as claimed in claim 1, wherein the composition of said magnetic layer is modulated in a direction in which a thickness thereof is taken so that the composition is of said first composition of GdFeCo on said light incident side of said magnetic layer, is of a third composition of GdTbFeCo towards said direction opposite to the light incident side, and is of said second composition of TbFeCo on said opposite side from the light incident side.
- 3. The magneto-optic recording medium as claimed in claim 1, wherein the composition of said magnetic layer is modulated in a direction in which a thickness thereof is taken so that the composition is of said first composition of GdFeCo on said light incident side of said magnetic layer, is of a third composition of GdDyFeCo towards a direction opposite to the light incident side, and is of said second composition of DyFeCo on an opposite side from the light incident side.
- 4. The magneto-optic recording medium as claimed in claim 1, wherein said reflecting layer is made of a material selected from a group consisting of Al, Au, Pt, Ag, Ta, Cu, W and alloys of arbitrarily selected ones of such metals.
- 5. The magneto-optic recording medium as claimed in claim 4, wherein said reflecting layer also functions as a heat radiating layer.
- 6. The magneto-optic recording medium as claimed in claim 1, wherein said reflecting layer also functions as a heat radiating layer.
- 7. The magneto-optic recording medium as claimed in claim 1, wherein said magnetic layer has a thickness which permits light to transmit through said magnetic layer.
- 8. A magneto-optic recording medium, comprising:
- a transparent substrate;
- a first dielectric layer provided above said transparent substrate;
- a magnetic layer provided above said first dielectric layer;
- a second dielectric layer provided above said magnetic layer; and
- a reflecting layer provided above said second dielectric layer,
- said magnetic layer being made of a composition modulated material which is modulated in a specific direction in which a thickness thereof is taken so that a composition of said magnetic layer gradually changes along said specific direction,
- said composition modulated material having at least a first composition on a light incident side of said magnetic layer, and a second composition on an opposite side from the light incident side, wherein said first and second compositions are different,
- said second dielectric layer and said reflecting layer causing an enhancement effect which is defined as an overlap of a Kerr rotation angle of light at a surface on the light incident side of said magnetic layer and a Faraday rotation angle of light which is transmitted through said magnetic layer and reflected by said reflecting layer.
- 9. The magnetic-optic recording medium as claimed in claim 8, wherein said magnetic layer has a thickness which permits light to transmit through said magnetic layer.
- 10. A magneto-optic recording medium which records information in conformance with a mark edge recording system, said mark edge recording system recording the information so that an edge of a recording mark formed on the magneto-optic recording medium corresponds to data value "1", said magneto-optic recording medium comprising:
- a transparent substrate;
- a first dielectric layer provided above said transparent substrate;
- a magnetic layer provided above said first dielectric layer;
- a second dielectric layer provided above said magnetic layer; and
- a reflecting layer provided above said second dielectric layer,
- said magnetic layer being made of a composition modulated material which is modulated in a specific direction in which a thickness thereof is taken so that a composition of said magnetic layer gradually changes along said specific direction,
- said composition modulated material having at least a first composition on a light incident side of said magnetic layer, and a second composition on an opposite side from the light incident side, wherein said first and second compositions are different,
- said second dielectric layer and said reflecting layer causing an enhancement effect which is defined as an overlap of a Kerr rotation angle of light at a surface on the light incident side of said magnetic layer and a Faraday rotation angle of light which is transmitted through said magnetic layer and reflected by said reflecting layer.
- 11. The magneto-optic recording medium as claimed in claim 10, wherein said magnetic layer has a thickness which permits light to transmit through said magnetic layer.
Priority Claims (1)
Number |
Date |
Country |
Kind |
5-218708 |
Sep 1993 |
JPX |
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Parent Case Info
This application is a continuation application of Ser. No. 08/222,946 filed Apr. 5, 1994, now abandoned.
US Referenced Citations (7)
Foreign Referenced Citations (8)
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0 051 296 |
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EPX |
0 330 394 |
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1-237945 |
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JPX |
Non-Patent Literature Citations (2)
Entry |
Patent Abstracts of Japan, vol. 7, No. 168 (P-212), Jul. 27, 1983, & JP-A-58 073 030. |
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Continuations (1)
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Number |
Date |
Country |
Parent |
222946 |
Apr 1994 |
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