公开(公告)号：JP2000298882A

公开(公告)日：2000-10-24

申请号：JP10596899

申请日：1999-04-13

Applicant: SONY CORP

Inventor： IKEDA ETSURO ,  MIURA HIROSHI ,  TANAKA FUJI ,  ARIMA MITSUO ,  OTOMO KATSUHIKO ,  SATO MANABU

IPC: G11B7/24

Abstract: PROBLEM TO BE SOLVED: To increase recording density and at the same time securely perform recording/reproduction. SOLUTION: A pit as a recessed and projecting pattern according to a recorded signal is formed at a lead-in area 1a (pit part) used exclusively for reproduction, and a group is formed along a record track at a program area 1b (group part) where a signal can be rewritten. Also, the lead-in area 1a and the program area 1b are formed so that a relationship Tg+0.01 (1.22λ/NA)

公开(公告)号：JP2000057636A

公开(公告)日：2000-02-25

申请号：JP22910898

申请日：1998-08-13

Applicant: SONY CORP

Inventor： IKEDA ETSURO ,  TAKENOUCHI MASAKI ,  DOI YUICHIRO ,  OTSUKI HIROSHI

IPC: G11B7/26

Abstract: PROBLEM TO BE SOLVED: To effectively use a release agent to decrease the number of test molding and to extend the period of maintenance by specifying the critical surface tension of a surface used as a pattern transfer face and improving the wettability of the surface. SOLUTION: The critical surface tension of a surface used as a pattern transfer face is made to >=40 dyn/cm. A fused resin material charged in a cavity between a pair of dies 21, 22 are pressurized, solidified by cooling and thereafter, taken out of the dies 21, 22 to obtain a disk substrate 30 in which a pattern formed on a stamper 10 is transferred. By previously adding a release agent internally to a resin material as a source material of the disk substrate 30, the surface of the stamper 10 is covered with the release agent to improve the releasing property for the formed disk substrate 30. By heat treating the stamper 10 at >=150 deg.C for >=15 min. in the air after produced and before used, the critical surface tension of the surface becomes >=40 dyn/cm and the release agent internally added to the resin material quickly bleeds out all over the surface of the stamper 10.

公开(公告)号：JPH11339325A

公开(公告)日：1999-12-10

申请号：JP14159998

申请日：1998-05-22

Applicant: SONY CORP

Inventor： NOMURA HIROSHI ,  IKEDA ETSURO ,  TAKENOUCHI MASAKI ,  FUJIMOTO TSUTOMU ,  KAIYA TADAKATSU

IPC: G11B7/26

Abstract: PROBLEM TO BE SOLVED: To provide a process for producing optical disks capable of greatly improving the mold parting property of a metallic master disk and to drastically reducing the number of times for 'trial molding'. SOLUTION: A disk substrate is manufactured by a stage for irradiation with UV rays for irradiating a metallic master disk 22 manufactured by a mastering stage and an injection molding stage for injection molding a plastic material by using the metallic master disk 22 subjected to a surface treatment by the irradiation with the UV rays and a reflection film and recording layer are formed thereon, by which the optical disk is produced. The org. matter, such as photoresist, remaining on the metallic master disk 22 is rapidly decomposed away when irradiated with the UV rays, by which the surface of the metallic master disk is cleaned.

公开(公告)号：JPH09153230A

公开(公告)日：1997-06-10

申请号：JP31141995

申请日：1995-11-29

Applicant: SONY CORP

Inventor： IKEDA ETSURO

IPC: G11B7/24 ,  G11B11/10 ,  G11B11/105

Abstract: PROBLEM TO BE SOLVED: To provide such an optical disk that has little warpage in the environmental temp. range for use and that causes no deterioration in the signal quality when the temp. changes. SOLUTION: This optical disk to be used for recording and reproducing by laser light is obtd. by forming a recording layer and a reflecting film 3 on the one principal surface of a plastic substrate 1 and forming a transparent film 4 on the other principal surface. The refractive index n1 of the transparent film 4 and the refractive index n0 of the substrate 1 are in the relation of n1

公开(公告)号：JPH097243A

公开(公告)日：1997-01-10

申请号：JP15440095

申请日：1995-06-21

Applicant: SONY CORP

Inventor： YOSHIDA MIKIO ,  IKEDA ETSURO

IPC: G11B11/10 ,  G11B7/24 ,  G11B7/254 ,  G11B11/105

Abstract: PURPOSE: To simplify the work, to shorten the time required for recording and to increase the recording density by making the protruded height of the front surface of a protection film of a magnetooptical disk smaller than the floating distance of a magnetic head. CONSTITUTION: After forming a recording layer on a substrate, it is irradiated with a laser beam L1 as shown by an arrow L1 from a light source (not shown in the figure),the beam is reflected by a beam splitter 42 arranged in the midway part, the front surface 41a of a protection film 41 is irradiated with the beam, the reflected light beam L2 is transmitted through the beam splitter 42, received by a position sensitive detector 43 and the displacement and the light quantity of the reflected beam are measured. When a protruded part does not exist on the front surface 41a of a protection film 41, the reflected beam is returned vertically to the front surface 41a of the protection film 41 i.e., upward in the figure. A magnetooptical disk is preferably manufactured by sorting only the protruded height smaller than a prescribed value.

公开(公告)号：JPH056582A

公开(公告)日：1993-01-14

申请号：JP5956791

申请日：1991-03-01

Applicant: SONY CORP

Inventor： IKEDA ETSURO ,  YOSHIKAWA MASAHIRO ,  KISHI TAKASHI

IPC: G11B11/10 ,  G11B11/105

Abstract: PURPOSE:To suppress the deterioration of the characteristics of the magneto- optical recording medium and to allow low-magnetic field recording. CONSTITUTION:This magneto-optical recording medium is constituted by laminating a dielectric layer on a recording layer consisting of a RE-TM magnetic film. The constituting elements of the dielectric layer intrudes into the RE-TM magnetic film according to film forming conditions, etc., and the region where the above-mentioned constituting elements intrude is confined to