公开(公告)号：JPH04105235A

公开(公告)日：1992-04-07

申请号：JP22400790

申请日：1990-08-24

Applicant: SONY CORP

Inventor： OCHIAI YOSHITAKA ,  MATSUDA HIDEKI ,  NAGAKI TAKEHIRO ,  HASHIMOTO SHUNICHI

IPC: G11B11/10 ,  G11B5/02 ,  G11B5/127 ,  G11B11/105

Abstract: PURPOSE:To allow the reproduction of tracks of a small track width with a sufficient sensitivity by irradiating a perpendicularly magnetized film with linearly polarized light and detecting the magnetization inversion of the perpendicularly magnetized film with the extreme Kerr effect. CONSTITUTION:The magnetic field components perpendicular to the film plane of the perpendicularly magnetized film 3 exist in the leak magnetic field near a 2nd gap G2. The perpendicularly magnetized film 3 is magnetized by this perpendicular leak magnetic field component. On the other hand, this leak magnetic field is inverted according to the magnetization state of a magnetic recording medium 5 and, therefore, the magnetization of the perpendicularly magnetized film 3 is inverted according to the magnetization state of the magnetic recording medium 5. Then, this perpendicularly magnetized film 3 is irradiated with the linearly polarized light and the extreme Kerr rotating angle is detected, by which the magnetization inversion of the perpendicularly magnetized film 3 is detected. The reproduction of the tracks having the small track width is executed with the high sensitivity in this way.

公开(公告)号：JPH0229956A

公开(公告)日：1990-01-31

申请号：JP17813488

申请日：1988-07-19

Applicant: SONY CORP

Inventor： HASHIMOTO SHUNICHI ,  OCHIAI YOSHITAKA ,  ASO KOICHI

IPC: G11B11/10 ,  G11B11/105

Abstract: PURPOSE:To obtain the magneto-optical recording medium having corrosion resistance and pitting corrosion resistance and excellent magnetic Kerr rotating angle and coercive force by forming a composite artificial lattice film laminated with Co-Pt artificial lattice films and Co-Pd artificial lattice films as a recording layer. CONSTITUTION:The Co-Pt artificial lattice films are formed by alternately laminating Co layers and Pt layers by sputtering on a substrate and further, the Co-Pd artificial lattice films are formed by alternately laminating Co layers and Pd layers by sputtering thereon. The composite artificial lattice film formed by laminating these films is used as the recording layer. Since the recording medium having the recording layer does not contain a rare earth element, the corrosion resistance is improved. The Co-Pt artificial lattice films having the excellent magnetic Kerr rotating angle and the coercive force and the Co-Pd artificial lattice films having the excellent coercive force are laminated, by which the recording layer having the characteristics of both in combination is used. The magneto-optical effect is thus improved without making combination use of an underlying film.

公开(公告)号：JPH01169757A

公开(公告)日：1989-07-05

申请号：JP32528887

申请日：1987-12-24

Applicant: SONY CORP

Inventor： HASHIMOTO SHUNICHI ,  OCHIAI YOSHITAKA ,  ASO KOICHI

IPC: G11B11/10 ,  G11B11/105

Abstract: PURPOSE:To improve coercive force and the square shape of a magnetic Kerr curve by forming a recording layer of artificial lattice films which are alternately laminated with a specific atomic layer number of Co and Pt and are specified in the total thickness thereof on a substrate on which an underlying ZnS film is formed. CONSTITUTION:The underlying ZnS layer 2 is formed on the glass substrate 1 and the recording layer 3 consisting of the Co-Pt artificial lattice films which are alternately laminated with Co 0.5-2.5atom. layers and Pt 1-7atom. layers and have 50-500Angstrom total thickness is formed on this layer 2. The range of the atomic layer number of the respective layers and the total thickness suppresses generation of an intra-surface magnetization component and optimizes magneto-optical characteristics. The coercive force and the square shape of the magnetic Kerr curve are improved and the shape of pits at the time of recording is sharpened; in addition, the S/N of reading out is improved by forming the recording layer 3 via the underlying ZnS layer 2 on the substrate in such a manner. The magneto-optical recording with high quality at a high density is thereby enabled.

公开(公告)号：JPH0198143A

公开(公告)日：1989-04-17

申请号：JP25602887

申请日：1987-10-09

Applicant: SONY CORP

Inventor： HASHIMOTO SHUNICHI ,  KANEKO MASAHIKO ,  OCHIAI YOSHITAKA ,  ASO KOICHI

IPC: H01F10/10 ,  C23C14/06 ,  G11B11/10 ,  G11B11/105

Abstract: PURPOSE:To suppress corrosion and pitting and to stably maintain a magneto- optical effect by forming a recording layer of thin films of a specific superlattice metal or thin films of a modulated structure metal. CONSTITUTION:The recording layer is formed of the thin films of the superlattice alloy or the thin films of the modulated structure metal formed by alternately laminating Ni layers of 3-8atom. layers and Pt layers of 1/2-2 the atomic layers. The respective metallic layers are formed by sputtering or vacuum evaporation. Si Ti, V, Cr, Mn, Fe, and other elements may be added to the recording layer in order to lower the Curie point.

公开(公告)号：JPS6435747A

公开(公告)日：1989-02-06

申请号：JP19173487

申请日：1987-07-31

Applicant: SONY CORP

Inventor： OCHIAI YOSHITAKA ,  HASHIMOTO SHUNICHI ,  ASO KOICHI

IPC: C22C28/00 ,  C22C29/00 ,  C22C32/00 ,  G11B11/10 ,  G11B11/105 ,  H01F10/12

Abstract: PURPOSE:To stably maintain a magneto-optical effect while suppressing corrosion and pitting by laminating a rare earth element layer and transition metal layer in the form of superlattice and adding Pt thereto. CONSTITUTION:The rare earth element layer and the transition metal layer are laminated in the form of superlattice and Pt is added thereto. Namely, the recording layer is formed of the superlattice structure of the rare earth element layer and the transition metal layer and 2-25atom.% Pt is incorporated therein as the entire compsn. While the corrosion and pitting are thereby prevented, the magneto-optical effect is stably maintained and a memory device which has a high density and high C/N and maintains the high reliability over a long period of time is thus obtd.

公开(公告)号：JPS63142415A

公开(公告)日：1988-06-14

申请号：JP28933286

申请日：1986-12-04

Applicant: SONY CORP

Inventor： TAMARU EIJI ,  AOYANAGI KATSUMI ,  HASHIMOTO SHUNICHI ,  KOIZUMI TAKAAKI

IPC: G06F3/045 ,  G06F3/03

Abstract: PURPOSE:To reduce an ineffective detection area by providing first and second resistors for detection of X and Y coordinates and supplying voltages to them independently of each other and providing the first resistor with gap. CONSTITUTION:First and second glass substrates 31 and 32 are put one over the other with a prescribed gap between them, and a transparent resistor 33 is provided on the lower face of the substrate 31, and electrodes 35 and 36 are provided in both end parts in the X-axis direction. A transparent resistor 34 is provided on the upper face of the substrate 32, and electrodes 37 and 38 are formed in both end parts in the Y-axis direction. Electrodes 35-38 are selectively connected to a signal source 23 (or the earth potential) through switches 40-43. A detecting electrode 25 is placed on the upper face of the substrate 31 to detect the position (coordinates) from the detecting electrode 25 by capacitive coupling. Since potentials are caused in two resistors 33 and 34 independently of each other in accordance with detection directions, the equipotential line is approximately straight throughout the surface of the substrate 31. As the result, the ineffective area is eliminated.

公开(公告)号：JPS6353736A

公开(公告)日：1988-03-08

申请号：JP19766886

申请日：1986-08-23

Applicant: SONY CORP

Inventor： HASHIMOTO SHUNICHI ,  OCHIAI YOSHITAKA ,  KANEKO MASAHIKO ,  ASO KOICHI ,  TAMURA HIDEMASA ,  WATANABE KENJIRO

IPC: G11B11/10 ,  G11B11/105

Abstract: PURPOSE:To improve corrosion resistance by forming a protective layer consisting of a rare earth element and transition metal element having the same compsn. as the compsn. of a recording layer and having the Kerr rotating angle larger than the Kerr rotating angle of the recording layer on the recording layer. CONSTITUTION:This recording medium is constituted of a transparent substrate 1, the recording layer 2 with which writing and reading out of information are executed by laser light, and the protective layer 3 which has high corrosion resistance and protects the recording layer 2. The recording layer 2 is a magnetic amorphous film consisting of the rare earth element and transition metal element and has perpendicular magnetic anisotropy. Said film is formed by sputtering in an Ar atmosphere. The gaseous Ar pressure at the time of the sputtering is set within a 10 -10 Torr range. On the other hand, the protective layer 3 is also a magnetic film consisting of the rare earth element and transition metal element having the same compsn. as the compsn. of the recording layer 2 and has the Kerr rotating angle greater than the Kerr rotating angle of the recording layer 2. The corrosion resistance is thereby improved without deteriorating the magneto-optical characteristics.

公开(公告)号：JPS6222887A

公开(公告)日：1987-01-31

申请号：JP16264885

申请日：1985-07-23

Applicant: SONY CORP

Inventor： HASHIMOTO SHUNICHI ,  ONO KATSUTOSHI

IPC: C09K11/08 ,  C09K11/84 ,  H01J29/20

Abstract: PURPOSE:To obtain a uniform white color through improvement in the dispersion of each color and, at the same time, to eliminate nonuniform luminescence due to the aggregation of a phosphor, by mixing a Y2O2S:Tb phosphor with a Y2O2S:Eu phosphor in a particular proportion. CONSTITUTION:A Y2O2S:Tb phosphor having a Tb concn. of 0.1-0.3mol% is mixed with a Y2O2S:Eu phosphor having a Eu concn. of 2-5mol% so as to have a Y2O2S:Tb phosphor concn. of 60-80wt%. Although the white phosphor is a mixture of two phosphors, they are the same as or similar to each other in properties such as specific gravity, because they are the same with each other in the matrix material. This enables mutual uniform dispersion and prevents occurrence of aggregation.