Patent US3055784A successfully refreshed from Google Patents.
US4417331A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for manufacturing an optical disc
Assignee: Toshiba Corp
•
Filing: 1981-02-17
•
Granted: 1983-11-22
•
Expires: 2001-02-17
Abstract
Abstract In an optical disk having an optical recording layer which is capable of having information thereon using a laser beam with information superposed by modulation there is formed a spiral protruding or recessed track having a width equal to about half or less of the wavelength of a laser beam to be used, this track being utilized as the guiding track of the laser beam. A method for manufacturing such an optical disk is also disclosed according to which a recessed track for tracking is formed by plastic deformation of the upper surface of an original disk with a hard processing stylus such as a diamond stylus. The original disk thus produced is utilized for forming an optical recording disk having a protruding or recessed guiding track.
Inventors
- 👤 Takashi Takaoka
- 👤 Masahiko Mochizuki
- 👤 Mitsuo Yamashita
- 👤 Tadao Miura
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 09:56
CPC Classifications
G; G11; G11B; G11B7/00; G11B7/24; G11B7/26
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
122 words
A method for manufacturing an optical recording disk having an optical recording layer in which information is written by irradiating a focussed laser beam modulated by the information, said method comprising the steps of: (a) plastically deforming a surface of an original disk to form a spiral recessed track having a width of 0.2 to 0.41 μm; (b) coating a metal layer on the original disk plastically deformed according to step (a); (c) separating the metal layer from the original disk to provide a relief mold; (d) forming a substrate having a recessed track by using the relief mold formed according to step (c) as a second original disk; and (e) coating an optical recording layer on the surface of the substrate.
Claim 2
Independent Claim
122 words
A method for manufacturing an optical recording disk having an optical recording layer in which information is written by irradiating a focussed laser beam modulated by the information, said method comprising the steps of: (a) plastically deforming a surface of an original disk to form a spiral recessed track having a width of 0.2 to 0.41 μm; (b) coating a metal layer on the original disk plastically deformed according to step (a); (c) separating the metal layer from the original disk to provide a relief mold; (d) forming a substrate having a recessed track by using the relief mold formed according to step (c) as a second original disk; and (e) coating an optical recording layer on the surface of the substrate.
Claim 3
Independent Claim
152 words
A method for manufacturing an optical recording disk having an optical recording layer in which information is written by irradiating a focussed laser beam modulated by the information, said method comprising the steps of: (a) plastically deforming a surface of an original disk to form a spiral recessed track having a width of 0.2 to 0.41 μm; (b) coating a metal layer on the original disk plastically deformed according to step (a); (c) separating the metal layer from the original disk to provide a second original disk; (d) coating a metal layer on the second original disk to provide a relief mold; (e) casting a synthetic resin layer on the relief mold; (f) forming a substrate having a protruding track by separating the synthetic resin layer and the relief mold and thus inverting the pattern of the recessed track; and (g) coating an optical recording layer on the surface on the substrate.
Claim 4
Independent Claim
152 words
A method for manufacturing an optical recording disk having an optical recording layer in which information is written by irradiating a focussed laser beam modulated by the information, said method comprising the steps of: (a) plastically deforming a surface of an original disk to form a spiral recessed track having a width of 0.2 to 0.41 μm; (b) coating a metal layer on the original disk plastically deformed according to step (a); (c) separating the metal layer from the original disk to provide a second original disk; (d) coating a metal layer on the second original disk to provide a relief mold; (e) casting a synthetic resin layer on the relief mold; (f) forming a substrate having a protruding track by separating the synthetic resin layer and the relief mold and thus inverting the pattern of the recessed track; and (g) coating an optical recording layer on the surface on the substrate.
References Cited (Backward Citations)
US3373997A
Cited
US3430966A
Cited
US3842194A
Cited
US4005259A
Cited
US4295162A
Cited
US4209793A
Cited
JPS55449A
Cited
US4209804A
Cited
GB2035661A
Cited
US4310919A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-11-21 | 1987-05-23 | 1987-11-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-11-21 | 1991-05-23 | 1991-11-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-11-21 | 1995-05-23 | 1995-11-22 | $7700.00 | Window Closed / Lapsed |