Patent US4533593A successfully refreshed from Google Patents.
US4533593A
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Antireflection coating for potassium chloride
Assignee: National Institute of Advanced Industrial Science and Technology
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Filing: 1983-09-16
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Granted: 1985-08-06
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Expires: 2003-09-16
Abstract
Abstract An antireflection coating for a potassium chloride substrate has a first arsenic trisulfide (As 2 S 3 ) layer, a lead fluoride (PbF 2 ) layer and a second arsenic trisulfide (As 2 S 3 ) layer which are formed on at least one major surface of the potassium chloride (KCl) substrate in the order named. The antireflection coating withstands to irradiate of a high-power carbon dioxide gas laser. The antireflection coating also has good optical characteristics and moisture resistance.
Inventors
- 👤 Takeo Miyata
- 👤 Takuhiro Ono
- 👤 Takashi Iwabuchi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 20:28
CPC Classifications
G; G02; G02B; G02B1/00; G02B1/10; G02B1/11; G02B1/113; G02B1/115; C; C30; C30B; C30B29/00; C30B29/10; C30B29/12; C30B33/00; G02B1/02; Y; Y10; Y10T; Y10T428/00; Y10T428/24; Y10T428/24942; Y10T428/2495; Y10T428/24967; Y10T428/26; Y10T428/261; Y10T428/263; Y10T428/264; Y10T428/265
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
58 words
An antireflection coating for a potassium chloride substrate, said coating comprising a first arsenic trisulfide (As 2 S 3 ) layer, a lead fluoride (PbF 2 ) layer and a second arsenic trisulfide (As 2 S 3 ) layer which are formed on at least one major surface of the potassium chloride (KCl) substrate in the order named.
Claim 2
Dependent Claim
58 words
An antireflection coating for a potassium chloride substrate, said coating comprising a first arsenic trisulfide (As 2 S 3 ) layer, a lead fluoride (PbF 2 ) layer and a second arsenic trisulfide (As 2 S 3 ) layer which are formed on at least one major surface of the potassium chloride (KCl) substrate in the order named.
Claim 3
Dependent Claim
61 words
A layer according to claim 1, wherein the first arsenic trisulfide (As 2 S 3 ) layer, the lead fluoride (PbF 2 ) layer and the second arsenic trisulfide (As 2 S 3 ) layer have optical thicknesses falling in ranges between 2.438 μm and 2.650 μm, between 1.259 μm and 1.363 μm, and between 0.959 μm and 1.038 μm, respectively.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-08-05 | 1989-02-04 | 1989-08-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-08-05 | 1993-02-04 | 1993-08-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-08-05 | 1997-02-04 | 1997-08-06 | $7700.00 | Window Closed / Lapsed |