EP0187718A2
Expired / Lapsed
EP
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A distributed feedback semiconductor laser device
Assignee: Sharp Corp
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Filing: 1986-01-09
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Granted: —
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Expires: 2006-01-09
Abstract
Abstract A distributed feedback semiconductor laser device comprises an active layer positioned between a first cladding layer and a second cladding layer, and an absorption layer positioned between said active layer and one of said cladding layers, said absorption layer having grooves to form a diffraction grating with a given periodicity in the direction of the propagation of laser light.
Inventors
- 👤 Toshihiko Yoshida
- 👤 Haruhisa Takiguchi
- 👤 Shinji 101 Kyobate Mansion Kaneiwa
- 👤 Sadayoshi Matsui
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-03 11:54
CPC Classifications
H; H01; H01S; H01S5/00; H01S5/10; H01S5/12; H01S5/1228; H01S5/20; H01S5/22; H01S5/223; H01S5/2232
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
60 words
A distributed feedback semiconductor laser device comprising an active layer positioned between a first cladding layer and a second cladding layer, and an absorption layer positioned between said active layer and one of said cladding layers, said absorption layer . having grooves to form a diffraction grating with a given periodicity in the direction of the propagation of laser light.
Claim 2
Dependent Claim
60 words
A distributed feedback semiconductor laser device comprising an active layer positioned between a first cladding layer and a second cladding layer, and an absorption layer positioned between said active layer and one of said cladding layers, said absorption layer . having grooves to form a diffraction grating with a given periodicity in the direction of the propagation of laser light.
Claim 3
Dependent Claim
32 words
A distributed feedback semiconductor laser device according to claim 1, wherein a buffer layer having the same polarity as said cladding layer is positioned between said active layer and said absorption layer.
Claim 4
Dependent Claim
43 words
A distributed feedback semiconductor laser device according to claim 1 or 2, wherein said absorption layer has an energy gap which is equal to or is somewhat narrower than that of said active layer and has the same polarity as said cladding layer.
Claim 5
Dependent Claim
66 words
A distributed feedback semiconductor laser device according to claim 2, wherein said absorption layer has a different polarity from that of said cladding layer and a reverse bias is applied to the junction at the interface between said buffer layer and said absorption layer, resulting in a current blocking structure having a diffraction grating with the same periodicity as the diffraction grating of said absorption layer.
References Cited (Backward Citations)
No citation records indexed.
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