Patent US4941146A successfully refreshed from Google Patents.
US4941146A
Expired / Lapsed
US
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Semiconductor laser device
Assignee: NEC Corp
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Filing: 1989-06-28
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Granted: 1990-07-10
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Expires: 2009-06-28
Abstract
Abstract A semiconductor laser device comprises an active layer of a refractive index n 1 , first and second inner cladding layers of a refractive index n 2 and a bandgap energy greater than that of the active layer provided on the both sides of the active layer to form a double heterostructure, and fist and second outer cladding layers of a refractive index n 3 provided on the both sides of the double heterostructure. The refractive indices n 1 , n 2 and n 3 meet a relation of "n 1 >n 3 >n 2 ", so that a vertical radiation angle of an output light beam is controlled in accordance with a thickness of the first and second inner cladding layers, and the refractive index n 3 , even if the active layer is thick.
Inventors
- 👤 Kenichi Kobayashi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 12:03
CPC Classifications
H; H01; H01S; H01S5/00; H01S5/20; H01S5/22; H01S5/223; H01S5/2231; H01S5/2004
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
132 words
A semiconductor laser device, comprising: a double heterostructure including an active layer and first and second inner cladding layers provided on both sides of said active layer, said double heterostructure being provided on a semiconductor substrate and a bandgap energy of said first and second inner cladding layers being greater than that of said active layer; first and second outer cladding layers provided on both sides of said double heterostructure; and first and second electrodes for applying a predetermined voltage across said double heterostructure; wherein a refractive index of said active layer is greater than a refractive index of said first and second outer cladding layers, and said refractive index of said first and second outer cladding layers is greater than a refractive index of said first and second inner cladding layers
Claim 2
Dependent Claim
132 words
A semiconductor laser device, comprising: a double heterostructure including an active layer and first and second inner cladding layers provided on both sides of said active layer, said double heterostructure being provided on a semiconductor substrate and a bandgap energy of said first and second inner cladding layers being greater than that of said active layer; first and second outer cladding layers provided on both sides of said double heterostructure; and first and second electrodes for applying a predetermined voltage across said double heterostructure; wherein a refractive index of said active layer is greater than a refractive index of said first and second outer cladding layers, and said refractive index of said first and second outer cladding layers is greater than a refractive index of said first and second inner cladding layers
Claim 3
Dependent Claim
50 words
A semiconductor laser device, according to claim 1 wherein: said first and second inner cladding layers are of a thickness dependent on a vertical radiation angle of an output light beam, and said first and second outer cladding layers are of a refractive index dependent on said vertical radiation angle.
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) | 1993-07-09 | 1994-01-08 | 1994-07-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-07-09 | 1998-01-08 | 1998-07-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-07-09 | 2002-01-08 | 2002-07-10 | $7700.00 | Window Closed / Lapsed |