US4975355A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Information storage medium
Assignee: Toshiba Corp
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Filing: 1989-06-28
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Granted: 1990-12-04
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Expires: 2009-06-28
Abstract
Abstract An optical disk comprises a polycarbonate substrate, a first protective layer formed on the substrate and made of SiO 2 , a recording layer formed on the first protective layer and made of an In-Sb-Te alloy, a second protective layer formed on the recording layer and made of SiO 2 , and a surface protective layer formed on the second protective layer and made of an ultraviolet curable resin. The recording layer has a composition of In 50-x Sb 50 Te x (wherein x is in atomic % and falls within the range of 0<x<20).
Inventors
- 👤 Katsumi Suzuki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 08:56
CPC Classifications
G; G11; G11B; G11B7/00; G11B7/24; G11B7/241; G11B7/252; G11B7/254; G11B7/242; G11B7/243; G11B2007/24302; G11B2007/2431; G11B2007/24314; G11B2007/24316; G11B7/253; G11B7/2533; G11B7/2534; G11B7/2542; G11B7/257; G11B7/2578; Y; Y10; Y10S; Y10S430/00; Y10S430/146
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
120 words
A method of recording information, comprising the steps of: providing an information storage medium comprising a substrate and a recording layer containing an amorphous In-Sb-Te alloy comprising In 50-x Sb 50 Te x , wherein x is in atomic % and falls within a range of 0<×<20; initializing the recording layer by continuous irradiation with a low power, large pulse width laser beam to convert the amorphous alloy into a crystalline phase having fine grains of SbTe dispersed among fine crystals of an InSb intermetallic compound; and recording information by irradiating the initialized layer with a high power, small pulse width laser beam to transform the SbTe into an amorphous state dispersed among fine crystals of an InSb intermetallic compound.
Claim 2
Independent Claim
120 words
A method of recording information, comprising the steps of: providing an information storage medium comprising a substrate and a recording layer containing an amorphous In-Sb-Te alloy comprising In 50-x Sb 50 Te x , wherein x is in atomic % and falls within a range of 0<×<20; initializing the recording layer by continuous irradiation with a low power, large pulse width laser beam to convert the amorphous alloy into a crystalline phase having fine grains of SbTe dispersed among fine crystals of an InSb intermetallic compound; and recording information by irradiating the initialized layer with a high power, small pulse width laser beam to transform the SbTe into an amorphous state dispersed among fine crystals of an InSb intermetallic compound.
Claim 3
Dependent Claim
36 words
A method as claimed in claim 1, additionally comprising the step of erasing recorded information by continuous irradiation with a low power, large pulse width laser beam to convert the amorphous SbTe into fine crystal grains.
Claim 4
Dependent Claim
17 words
A method according to claim 2, wherein said alloy contains Te of 1 to 10 atomic %.
References Cited (Backward Citations)
US4460636A
Cited
US4449138A
Cited
US4637976A
Cited
JPS60177446A
Cited
EP0184452A2
Cited
US4635076A
Cited
US4808514A
Cited
US4818666A
Cited
US4731755A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-12-03 | 1994-06-04 | 1994-12-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-12-03 | 1998-06-04 | 1998-12-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-12-03 | 2002-06-04 | 2002-12-04 | $7700.00 | Window Closed / Lapsed |