US4975922A
Expired / Lapsed
US
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Multi-layered dielectric film
Assignee: Sharp Corp
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Filing: 1989-06-19
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Granted: 1990-12-04
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Expires: 2009-06-19
Abstract
Abstract A multi-layered dielectric film that is coated on the end surfaces or other surfaces of optical products, wherein said multi-layered dielectric film is composed of alternate layers consisting of two kinds of dielectric layer, one of which is a first dielectric layer of TiO 2 or ZnS with a high refractive index n 1 and the other of which is a second dielectric layer of Al 2 O 3 with a low refractive index n 2 .
Inventors
- 👤 Chitose Sakane
- 👤 Haruhisa Takiguchi
- 👤 Hiroaki Kudo
- 👤 Satoshi Sugahara
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 04:31
CPC Classifications
G; G02; G02B; G02B1/00; G02B1/10; H; H01; H01S; H01S5/00; H01S5/02; H01S5/028; H01S5/0281
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
65 words
A multi-layered dielectric film coated on the end surfaces or other surfaces of optical products, wherein the multi-layered dielectric film comprises alternate dielectric layers, one of which is a first dielectric layer of TiO 2 with a high refractive index n 1 and the other of which is a second dielectric layer of Al 2 O 3 with a lower refractive index n 2 .
Claim 2
Dependent Claim
65 words
A multi-layered dielectric film coated on the end surfaces or other surfaces of optical products, wherein the multi-layered dielectric film comprises alternate dielectric layers, one of which is a first dielectric layer of TiO 2 with a high refractive index n 1 and the other of which is a second dielectric layer of Al 2 O 3 with a lower refractive index n 2 .
Claim 3
Dependent Claim
32 words
A multi-layered dielectric film according to claim 1, wherein said optical products are semiconductor laser devices and said end surfaces are the facets of said laser devices that are formed by cleavage.
References Cited (Backward Citations)
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 |