JPS6187252A - Photothermomagnetic recording medium - Google Patents
Photothermomagnetic recording mediumInfo
- Publication number
- JPS6187252A JPS6187252A JP60222921A JP22292185A JPS6187252A JP S6187252 A JPS6187252 A JP S6187252A JP 60222921 A JP60222921 A JP 60222921A JP 22292185 A JP22292185 A JP 22292185A JP S6187252 A JPS6187252 A JP S6187252A
- Authority
- JP
- Japan
- Prior art keywords
- light
- layer
- recording
- substrate
- film
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Classifications
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B11/00—Recording on or reproducing from the same record carrier wherein for these two operations the methods are covered by different main groups of groups G11B3/00 - G11B7/00 or by different subgroups of group G11B9/00; Record carriers therefor
- G11B11/10—Recording on or reproducing from the same record carrier wherein for these two operations the methods are covered by different main groups of groups G11B3/00 - G11B7/00 or by different subgroups of group G11B9/00; Record carriers therefor using recording by magnetic means or other means for magnetisation or demagnetisation of a record carrier, e.g. light induced spin magnetisation; Demagnetisation by thermal or stress means in the presence or not of an orienting magnetic field
- G11B11/105—Recording on or reproducing from the same record carrier wherein for these two operations the methods are covered by different main groups of groups G11B3/00 - G11B7/00 or by different subgroups of group G11B9/00; Record carriers therefor using recording by magnetic means or other means for magnetisation or demagnetisation of a record carrier, e.g. light induced spin magnetisation; Demagnetisation by thermal or stress means in the presence or not of an orienting magnetic field using a beam of light or a magnetic field for recording by change of magnetisation and a beam of light for reproducing, i.e. magneto-optical, e.g. light-induced thermomagnetic recording, spin magnetisation recording, Kerr or Faraday effect reproducing
-
- G—PHYSICS
- G11—INFORMATION STORAGE
- G11B—INFORMATION STORAGE BASED ON RELATIVE MOVEMENT BETWEEN RECORD CARRIER AND TRANSDUCER
- G11B11/00—Recording on or reproducing from the same record carrier wherein for these two operations the methods are covered by different main groups of groups G11B3/00 - G11B7/00 or by different subgroups of group G11B9/00; Record carriers therefor
- G11B11/10—Recording on or reproducing from the same record carrier wherein for these two operations the methods are covered by different main groups of groups G11B3/00 - G11B7/00 or by different subgroups of group G11B9/00; Record carriers therefor using recording by magnetic means or other means for magnetisation or demagnetisation of a record carrier, e.g. light induced spin magnetisation; Demagnetisation by thermal or stress means in the presence or not of an orienting magnetic field
- G11B11/105—Recording on or reproducing from the same record carrier wherein for these two operations the methods are covered by different main groups of groups G11B3/00 - G11B7/00 or by different subgroups of group G11B9/00; Record carriers therefor using recording by magnetic means or other means for magnetisation or demagnetisation of a record carrier, e.g. light induced spin magnetisation; Demagnetisation by thermal or stress means in the presence or not of an orienting magnetic field using a beam of light or a magnetic field for recording by change of magnetisation and a beam of light for reproducing, i.e. magneto-optical, e.g. light-induced thermomagnetic recording, spin magnetisation recording, Kerr or Faraday effect reproducing
- G11B11/10582—Record carriers characterised by the selection of the material or by the structure or form
- G11B11/10586—Record carriers characterised by the selection of the material or by the structure or form characterised by the selection of the material
Landscapes
- Optical Record Carriers And Manufacture Thereof (AREA)
Abstract
Description
【発明の詳細な説明】
本発明はレーザ等の光を用いて情報の記録、再生を行う
光熱磁気記録媒体に関するものである。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a photothermal magnetic recording medium that records and reproduces information using light such as a laser.
従来よりこの種の光熱磁気記録媒体には、第１図に示す
ように、ガラスやプラスチック等の基板ｌ上に光熱磁気
記録用の磁気記録層２として、例えばＭｎＢｆ、ＴｂＦ
ｅＤ３ 、ＧｄＩＧ、ＧｄＣｏ、ＧｄＦｅ、ＴｂＦｅ、
ＧｄＴｂＦｅ等の薄膜を形成し、さらに磁気記録層２の
面上を保護Ｎ３で被覆した構成のものが多く用いられて
いる。これらの光熱磁気記録媒体に記録再生を行う場合
には、第１図に示すように、矢印Ａ又はＢ方向からレー
ザ光線を照射して記録、再生を行うのが一般的であるが
、この場合、レーザ光線は磁気記録層２に到達する前に
、保工〜層３もしくは基板ｌによって少なくとも数％〜
１０％程度の反射損失があるために、照射されたレーザ
光線を１００％全て磁気記録層に与えることは不可能で
ある。Conventionally, as shown in FIG. 1, this type of photothermal magnetic recording medium has a magnetic recording layer 2 for photothermal magnetic recording on a substrate l made of glass or plastic, for example, MnBf, TbF.
eD3, GdIG, GdCo, GdFe, TbFe,
A structure in which a thin film of GdTbFe or the like is formed and the surface of the magnetic recording layer 2 is further coated with protective N3 is often used. When recording and reproducing on these photothermal magnetic recording media, it is common to record and reproduce by irradiating a laser beam from the direction of arrow A or B, as shown in Figure 1. , before the laser beam reaches the magnetic recording layer 2, it is damaged by at least several percent by the layer 3 or the substrate l.
Since there is a reflection loss of about 10%, it is impossible to apply all 100% of the irradiated laser beam to the magnetic recording layer.
本発明は上述の欠点を除去すると同時に、記録及び再生
時の効率を上げ、記録再生のＳ／Ｎ比を向上せしめた光
熱磁気記録媒体を提供することを目的とするものである
。SUMMARY OF THE INVENTION An object of the present invention is to provide a photothermal magnetic recording medium which eliminates the above-mentioned drawbacks, improves efficiency during recording and reproduction, and improves the S/N ratio of recording and reproduction.
以下、本発明を実施例に基づき具体的に説明する。Hereinafter, the present invention will be specifically explained based on Examples.
第２図は、本発明の第１の実施例で、透明なガラス基板
１１上に磁気記録層１２として高周波スパッタ法により
、ＧｄＴｂＦｅ膜を厚さ０．１ｇｍ程形酸形成該記録層
１２の表面に保護層１３として５ｉ０２スパツタ膜を０
．５＃程形成したものを用意し、ガラス基板１１の記録
層の存在しない方の面上に反射防止層１４としてＭｇＦ
２を蒸着法により形成した。上記ＭｇＦ２の膜厚は記録
、再生に用いる光の波長によるが、第１の実施例では約
１５０ＯＡとした。FIG. 2 shows a first embodiment of the present invention, in which a GdTbFe film is formed on a transparent glass substrate 11 as a magnetic recording layer 12 to a thickness of about 0.1 g by high frequency sputtering on the surface of the recording layer 12. A 5i02 sputtered film was applied as the protective layer 13.
．． MgF is prepared as an anti-reflection layer 14 on the surface of the glass substrate 11 on which the recording layer is not present.
2 was formed by a vapor deposition method. The thickness of the MgF2 film depends on the wavelength of the light used for recording and reproduction, but in the first example, it was approximately 150 OA.
その理由として、一般に透明基板の屈折率をｎｓとし、
その上に形成すべき反射防止膜の屈折率及び膜厚をｎ、
ｄとし、入射光線の波長をλとしたとき、光線入に対す
る反射防止（反射率が極小値を有する）条件としては、
１（空気の屈折率）＜ｎｕｎｓなるｎに対してｎ ｄ＝
（２ｍ＋１）λ／４
（ｍ＝ｏ、１＊２＋３・・＠）
を満足させれば良いことは良く知られている。The reason is that generally the refractive index of the transparent substrate is ns,
The refractive index and film thickness of the antireflection film to be formed on it are n,
d and the wavelength of the incident light beam is λ, the anti-reflection condition for the incident light beam (the reflectance has a minimum value) is as follows: 1 (refractive index of air) < nuns, n d =
It is well known that it is sufficient to satisfy (2m+1)λ/4 (m=o, 1*2+3...@).
第１の実施例では、ｎｄ＝入／４の式において、ＭｇＦ
２の屈折率ｎ ＝ １−３８４ 、記録、再生波長入−
８２０ＯＡを用いて、ＭｇＦ２の膜厚ｄ＃１５００Ａを
選定したものである。In the first embodiment, in the equation nd=in/4, MgF
2 refractive index n = 1-384, recording and reproduction wavelength input -
820OA and a MgF2 film thickness d#1500A was selected.
本実施例に示した構成の媒体をＭｇＦ２の面より矢印Ｂ
方向にレーザ光（波長８２００Ａ）を照射して磁気記録
層１２へ直径２．０１Ｌｍのドツト記録を行い、更に同
一波長のレーザ光にて磁気光学効果により再生を行った
結果、ＭｇＦ２を備えた媒体はＭｇＦ２をつけない媒体
に比べて、記録効率で１３％、再生効率で１１％の向上
が認められた。The medium having the configuration shown in this example is viewed from the MgF2 surface by arrow B
A dot with a diameter of 2.01 Lm was recorded on the magnetic recording layer 12 by irradiating a laser beam (wavelength 8200A) in the same direction, and then reproduction was performed using the magneto-optic effect using a laser beam of the same wavelength. As a result, a medium containing MgF2 was created. Compared to the medium without MgF2, recording efficiency was improved by 13% and reproduction efficiency was improved by 11%.
このように透明基板の光照射面上に基板からの反射を防
止する膜を形成することにより、磁気記録層への光の到
達率を上げ、光による記録、再生の効率を高めることが
回部である。By forming a film on the light irradiation surface of the transparent substrate to prevent reflection from the substrate, it is possible to increase the rate of light reaching the magnetic recording layer and improve the efficiency of optical recording and reproduction. It is.
第１の実施例では、ｎｄｗλ／４なる条件を満足させる
ようにＭｇＦ２の！！厚を決めたが、もちろん、ｎｄ＝
−λ、−人・・・等の条件を満足させる膜厚にしても同
様の効果が期待できる。In the first embodiment, MgF2 is adjusted to satisfy the condition ndwλ/4! ! I decided on the thickness, but of course, nd=
A similar effect can be expected even if the film thickness satisfies the conditions such as -λ, -person, etc.
第３図は、本発明の第２の実施例であり、第１の実施例
で用いたＭｇＦ２の代わりに反射防止層１４として氷晶
石（３ＮａＦ＠Ａ！１Ｆ３）を用いた例を示す、このと
き、氷晶石の屈折率は偏光解析法により屈折率１．３３
４ （入＝８２００）、に対して）であったので、そ
の膜厚は４６０ＯＡとした、（ｎｄ＝−λを使用）
上記第２の実施例に示す媒体を記録再生実験した結果第
１の実施例と同様の効果があることが確かめられた。上
記２つの実施例に挙げた構成の媒体では、第２，３図に
おいて、矢印Ｂ方向から光を照射して記録、再生を行う
場合であり、この場合磁気記録層２を被覆している保護
層３は必ずしも透明である必要はない。FIG. 3 is a second embodiment of the present invention, and shows an example in which cryolite (3NaF@A!1F3) is used as the antireflection layer 14 instead of MgF2 used in the first embodiment. At this time, the refractive index of cryolite was determined to be 1.33 by ellipsometry.
4 (for input = 8200)), so the film thickness was set to 460OA (nd = -λ was used) As a result of recording and reproducing experiments on the medium shown in the second example above, the first It was confirmed that the same effect as in the example was obtained. In the media having the configurations listed in the above two embodiments, recording and reproduction are performed by irradiating light from the direction of arrow B in FIGS. 2 and 3, and in this case, the protective layer covering the magnetic recording layer 2 Layer 3 does not necessarily have to be transparent.
第４図は、第１図に示すように透明な保護層を介して記
録層に光を照射する場合に１本発明に係る光熱磁気記録
媒体の一実施例を示す断面図である。第４図に示す如く
、基板ｌｌ上の記録層１２を覆う透明な保護層１３の上
には反射防止層１４が設けられており、保護層１３の表
面で反射される光を減少させることにより、上述した実
施例と同様の効果を持つ、もちろん、この構成では記録
、再生時にはＡ方向から光を照射して行うものである。FIG. 4 is a sectional view showing an embodiment of the photothermal magnetic recording medium according to the present invention when the recording layer is irradiated with light through a transparent protective layer as shown in FIG. As shown in FIG. 4, an anti-reflection layer 14 is provided on the transparent protective layer 13 covering the recording layer 12 on the substrate 11, and reduces the amount of light reflected on the surface of the protective layer 13. , which has the same effect as the embodiment described above. Of course, in this configuration, light is irradiated from the A direction during recording and reproduction.
第５図及び第６図は、本発明に係る光熱磁気記録媒体の
他の実施例を示すものである。ｆｌＳ５図は、一枚の基
板１１の両側に記録層（１２゜１２′）を設ける場合の
実施例を示すもので、これ等の記録層（１２，１２’）
の上には保護層（１３，１３’）が設けられており、更
にその上には反射防止層（１４，１４’）が設けられて
いる。5 and 6 show other embodiments of the photothermal magnetic recording medium according to the present invention. Figure flS5 shows an example in which recording layers (12° 12') are provided on both sides of one substrate 11, and these recording layers (12, 12')
A protective layer (13, 13') is provided on top of the protective layer, and an antireflection layer (14, 14') is further provided on top of the protective layer (13, 13').
そして記録層１２の記録、再生時にはＡ方向から、記録
層１２’の記録、再生時にはＢ方向より光の照射を行う
、第６図は、透明な基板（１１゜１１’）を通して該基
板上に設けられた記録層（１２，１２’）を照射する記
録媒体を、二個対向して配したもので各々の記録媒体ス
ペーサー１５を介して一体となっている。尚、１６は各
々の媒体で囲まれた空間であり、各々の保護層（１３゜
１３′）が透明である場合は、この空間に光吸収性の物
質を充填する。一方、保護層（１３，１３’）が光吸収
性の物質で構成されている場合には、１６は空間のまま
であっても良い、そして、記録層１２の記録、再生を行
う場合にはＡ方向から、記録層１２′の記録、再生を行
う場合にはＢ方向から光を照射するものであるが、いず
れの場合も、反射防止層（１４，１４’）により、効率
良く光エネルギーの取り込みを行うものである。Light is irradiated from the direction A when recording and reproducing the recording layer 12, and from the direction B when recording and reproducing the recording layer 12'. Two recording media for irradiating the provided recording layer (12, 12') are arranged facing each other and are integrated with each recording medium spacer 15 interposed therebetween. Note that 16 is a space surrounded by each medium, and if each protective layer (13° 13') is transparent, this space is filled with a light-absorbing substance. On the other hand, when the protective layer (13, 13') is made of a light-absorbing substance, 16 may remain a space, and when recording and reproducing the recording layer 12, When recording or reproducing information on the recording layer 12' from direction A, light is irradiated from direction B. In either case, the antireflection layer (14, 14') efficiently absorbs light energy. This is for importing data.
以上説明したように、熱磁気記録媒体の記録再生に用い
る光の照射面に、その光の波長に対して基板もしくは保
護層表面からの反射を防ぐことの可能な膜を形成するこ
とにより光による記録、再生の効率を高める効果がある
。As explained above, by forming a film on the light irradiation surface used for recording and reproducing of a thermomagnetic recording medium that can prevent the wavelength of the light from being reflected from the substrate or the surface of the protective layer, It has the effect of increasing the efficiency of recording and playback.
尚、本実施例では、いずれも単層反射防止層を用いてい
るが、２Ｍ以上の構成を有する反射防止層を用いても本
考案の主旨に何ら相違することはない。In this example, a single-layer antireflection layer is used, but the gist of the present invention does not differ even if an antireflection layer having a structure of 2M or more is used.
第１図は従来の光熱磁気記録媒体の構成を示す断面図、
第２図、第３図、第４図、第５図及び第６図は各々本発
明の光熱磁気記録媒体の構成を示す断面図。
１１ 、１１’−−−−一基板
１２ 、１２’−−−−一記録層
１３ 、１３’−−−−一保護層
１４ 、 ｌ ４’−−−−一反射防止層１５−−−−
−スペーサーFIG. 1 is a sectional view showing the structure of a conventional photothermal magnetic recording medium.
FIG. 2, FIG. 3, FIG. 4, FIG. 5, and FIG. 6 are cross-sectional views each showing the structure of the photothermal magnetic recording medium of the present invention. 11, 11'---- one substrate 12, 12'---- one recording layer 13, 13'---- one protective layer 14, l4'---- one antireflection layer 15----
−Spacer
Claims (1)
るための磁気記録層と、該磁気記録層を保護するための
保護層を設け、当該磁気記録層に基板もしくは保護層を
通して光を照射することにより情報の記録又は再生を行
い得る光熱磁気記録媒体において、基板もしくは保護層
の光入射側の面に反射防止膜を形成せしめたことを特徴
とする光熱磁気記録媒体。It has at least one substrate, a magnetic recording layer for recording information on the substrate, and a protective layer for protecting the magnetic recording layer, and light is emitted to the magnetic recording layer through the substrate or the protective layer. 1. A photothermal magnetic recording medium capable of recording or reproducing information by irradiation, characterized in that an antireflection film is formed on the light incident side surface of a substrate or a protective layer.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP60222921A JPS6187252A (en) | 1985-10-07 | 1985-10-07 | Photothermomagnetic recording medium |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP60222921A JPS6187252A (en) | 1985-10-07 | 1985-10-07 | Photothermomagnetic recording medium |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS6187252A true JPS6187252A (en) | 1986-05-02 |
Family
ID=16789948
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP60222921A Pending JPS6187252A (en) | 1985-10-07 | 1985-10-07 | Photothermomagnetic recording medium |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6187252A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS63292441A (en) * | 1987-05-26 | 1988-11-29 | Fuji Electric Co Ltd | Magneto-optical recording medium |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS50120933A (en) * | 1974-03-11 | 1975-09-22 | ||
| JPS52132850A (en) * | 1976-04-30 | 1977-11-07 | Hitachi Ltd | Light recording apparatus |
| JPS5525245A (en) * | 1978-08-10 | 1980-02-22 | Matsushita Electric Ind Co Ltd | Color signal demodulator circuit |
-
1985
- 1985-10-07 JP JP60222921A patent/JPS6187252A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS50120933A (en) * | 1974-03-11 | 1975-09-22 | ||
| JPS52132850A (en) * | 1976-04-30 | 1977-11-07 | Hitachi Ltd | Light recording apparatus |
| JPS5525245A (en) * | 1978-08-10 | 1980-02-22 | Matsushita Electric Ind Co Ltd | Color signal demodulator circuit |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS63292441A (en) * | 1987-05-26 | 1988-11-29 | Fuji Electric Co Ltd | Magneto-optical recording medium |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| JP2547768B2 (en) | Optical magnetic recording medium | |
| JPS6187252A (en) | Photothermomagnetic recording medium | |
| JPH0263262B2 (en) | ||
| JP2955112B2 (en) | Magneto-optical storage media | |
| JPH0264944A (en) | Magneto-optical recording medium | |
| KR100209585B1 (en) | Magneto-optical disk | |
| JPH039546B2 (en) | ||
| JPH0479076B2 (en) | ||
| KR100225109B1 (en) | Optic-magneto disc | |
| JPH06349137A (en) | Amorphous or quasi-amorphous film structure for optical or magneto-optical data storage medium, optical data storage device and its manufacture | |
| JP3236977B2 (en) | Manufacturing method of optical recording medium | |
| JP2787077B2 (en) | Magneto-optical recording medium | |
| JPH06187665A (en) | Optical recording medium of high density and optical recorder using the same | |
| JP2740814B2 (en) | Magneto-optical recording medium | |
| JPH0721584A (en) | Optical information recording medium | |
| JPH04318346A (en) | Magneto-optical recording medium | |
| JPS61273756A (en) | Optical disk | |
| JPS63124249A (en) | Magneto-optical disk | |
| JPH04337543A (en) | Magneto-optical recording medium | |
| JPS5911555A (en) | Opto-magnetic recording medium | |
| JPH038148A (en) | Magneto-optical recording medium | |
| JPH07186541A (en) | Optical recording medium | |
| JPH0524571B2 (en) | ||
| JPS62226449A (en) | Optical magnetic recording medium | |
| JPH09153239A (en) | Information memory medium |