Patent US4602370A successfully refreshed from Google Patents.
US4602370A
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US
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Large optical cavity laser having a plurality of active layers
Assignee: Nokia Bell Labs
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Filing: 1983-05-12
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Granted: 1986-07-22
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Expires: 2003-05-12
Abstract
Abstract A large optical cavity injection laser having a plurality of active layers within the large optical cavity. The active layers having a thickness great enough so that quantum effects are not significant.
Inventors
- 👤 Won-Tien Tsang
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 23:30
CPC Classifications
H; H01; H01S; H01S5/00; H01S5/20; H01S5/40; H01S5/4025; H01S5/4031; H01S5/4043; H01S5/2004
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
91 words
A semiconductor laser comprising a first cladding layer having a first conductivity type, a second cladding layer having a second conductivity type, and a large optical cavity, said large optical cavity being between said first cladding layer and said second cladding layer, said large optical cavity comprising a plurality of active layers having a first bandgap interleaved with a plurality of spacer layers having a second bandgap, said first bandgap being less than said second bandgap, said active layers having a thickness great enough so that quantum effects are not significant.
Claim 2
Dependent Claim
91 words
A semiconductor laser comprising a first cladding layer having a first conductivity type, a second cladding layer having a second conductivity type, and a large optical cavity, said large optical cavity being between said first cladding layer and said second cladding layer, said large optical cavity comprising a plurality of active layers having a first bandgap interleaved with a plurality of spacer layers having a second bandgap, said first bandgap being less than said second bandgap, said active layers having a thickness great enough so that quantum effects are not significant.
Claim 3
Dependent Claim
22 words
A semiconductor laser as recited in claim 1 in which said spacer layers have a thickness smaller than the carrier diffusion length.
Claim 4
Dependent Claim
22 words
A laser as recited in claim 2 in which said large optical cavity has a thickness smaller than the carrier diffusion length.
Claim 5
Dependent Claim
21 words
A laser as recited in claim 3 in which said spacer layers have a thickness greater than the carrier tunneling distance.
Claim 6
Dependent Claim
32 words
A laser as recited in claim 4 in which the difference in said first and second bandgaps permits carriers to move by thermionic emission between active layers in said large optical cavity.
Claim 7
Dependent Claim
26 words
A laser as recited in claim 5 in which said layers comprise materials selected from the group consisting of Group III-V and Group III-VI compound semiconductors.
Claim 8
Dependent Claim
22 words
A laser as recited in claim 6 in which said materials are selected from the group consisting of Group III-V compound semiconductors.
Claim 9
Dependent Claim
25 words
A laser as recited in claim 7 in which said Group III-V compound semiconductors are selected from the group consisting of AlGaAs, InGaAsP and GaAlInAs.
Claim 10
Dependent Claim
28 words
A laser as recited in claim 8 in which said active layers comprise Al x Ga 1-x As, and said spacer layers comprise Al y Ga 1-y As.
Claim 11
Dependent Claim
15 words
A laser as recited in claim 9 in which y is less than approximately 0.2+x.
References Cited (Backward Citations)
US4163238A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-07-21 | 1990-01-20 | 1990-07-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-07-21 | 1994-01-20 | 1994-07-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-07-21 | 1998-01-20 | 1998-07-22 | $7700.00 | Window Closed / Lapsed |