US5727015A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Distributed feedback semiconductor laser
Assignee: Sharp Corp
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Filing: 1996-03-06
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Granted: 1998-03-10
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Expires: 2016-03-06
Abstract
Abstract A gain coupled distributed feedback semiconductor laser includes an active layer and a diffraction grating provided in the vicinity of the active layer and having a plurality of light absorption layers periodically arranged along a resonator length direction. The order of the diffraction grating is one, a duty of the diffraction grating is in the range of about 0.4 to about 0.8, and a thickness of the light absorption layer is in the range of about 6 nm to about 30 nm.
Inventors
- 👤 Koji Takahashi
- 👤 Fumihiro Kounushi
- 👤 Mototaka Taneya
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 18:02
CPC Classifications
H; H01; H01S; H01S5/00; H01S5/10; H01S5/12; H01S5/1228
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
83 words
A gain coupled distributed feedback semiconductor laser, comprising: an active layer; and a diffraction grating provided in the vicinity of said active layer and having a plurality of light absorption layers periodically arranged along a resonator length direction, wherein the order of said diffraction grating is one, a duty of said diffraction grating is in the range of about 0.4 to about 0.8, and a thickness of said light absorption layer is in the range of about 6 nm to about 30 nm.
Claim 2
Dependent Claim
83 words
A gain coupled distributed feedback semiconductor laser, comprising: an active layer; and a diffraction grating provided in the vicinity of said active layer and having a plurality of light absorption layers periodically arranged along a resonator length direction, wherein the order of said diffraction grating is one, a duty of said diffraction grating is in the range of about 0.4 to about 0.8, and a thickness of said light absorption layer is in the range of about 6 nm to about 30 nm.
Claim 3
Dependent Claim
20 words
A distributed feedback semiconductor laser according to claim 1, wherein the effective duty of said diffraction grating is about 0.5.
Claim 4
Dependent Claim
38 words
A distributed feedback semiconductor laser according to claim 1, wherein a cross-sectional shape of said plurality of light absorption layers sectioned along a plane perpendicular to said active layer and parallel to said resonator length direction is rectangular.
Claim 5
Dependent Claim
38 words
A distributed feedback semiconductor laser according to claim 1, wherein a cross-sectional shape of said plurality of light absorption layers sectioned along a plane perpendicular to said active layer and parallel to said resonator length direction is triangular.
Claim 6
Dependent Claim
62 words
A distributed feedback semiconductor laser according to claim 1, wherein an effective forbidden band width of said light absorption layer is smaller than an effective forbidden band width of said active layer, and a difference between the effective forbidden band width of said light absorption layer and the effective forbidden band width of said active layer is about 0.126 eV or greater.
Claim 7
Dependent Claim
88 words
A distributed feedback semiconductor laser according to claim 1, wherein an effective forbidden band width of said light absorption layer is smaller than an effective forbidden band width of said active layer, and a difference between the effective forbidden band width of said light absorption layer and the effective forbidden band width of said active layer is about 0.126 eV or greater, and said active layer is formed of Al x Ga 1-x As, said light absorption layer is formed of Al y Ga 1-y As, and x-y≧0.1.
Claim 8
Dependent Claim
29 words
A distributed feedback semiconductor laser according to claim 1, wherein a thickness of said light absorption layer is in the range of about 12 nm to about 20 nm.
Claim 9
Dependent Claim
92 words
A gain coupled distributed feedback semiconductor laser oscillating at a wavelength shorter than about 1 μm comprising: an active layer; and a diffraction grating provided in the vicinity of said active layer and having a plurality of light absorption layers periodically arranged along a resonator length direction, wherein the order of said diffraction grating is one, a duty of said diffraction grating is in the range of about 0.4 to about 0.8, and a thickness of said light absorption layer is in the range of about 6 nm to about 30 nm.
Claim 10
Dependent Claim
92 words
A gain coupled distributed feedback semiconductor laser oscillating at a wavelength shorter than about 1 μm comprising: an active layer; and a diffraction grating provided in the vicinity of said active layer and having a plurality of light absorption layers periodically arranged along a resonator length direction, wherein the order of said diffraction grating is one, a duty of said diffraction grating is in the range of about 0.4 to about 0.8, and a thickness of said light absorption layer is in the range of about 6 nm to about 30 nm.
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