US4780879A
Expired / Lapsed
US
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Semiconductor laser device having little astigmatism
Assignee: Opnext Japan Inc
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Filing: 1987-02-19
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Granted: 1988-10-25
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Expires: 2007-02-19
Abstract
Abstract A semiconductor laser device having a stripe-shaped active region defined between a pair of end surfaces, at least one of the end surfaces having a curved cross-section in a plane parallel to the active region with a radius of curvature from 10 to 300 μm, the stripe of the active region having such a width that a single transverse mode and a multi-longitudinal mode are allowed. The laser beam emitted from this laser can have little astigmatism and small spot size.
Inventors
- 👤 Naoki Chinone
- 👤 Shigeo Yamashita
- 👤 Shin'ichi Nakatsuka
- 👤 Akemi Yamanaka
- 👤 Yuichi Ono
- 👤 Toshihiro Kawano
- 👤 Kazuhisa Uomi
- 👤 Takashi Kajimura
- 👤 Toshiaki Tanaka
- 👤 Kunio Aiki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 20:38
CPC Classifications
H; H01; H01S; H01S5/00; H01S5/10; H01S5/1082; H01S5/02; H01S5/026; H01S5/0267; H01S5/1053; H01S5/1064
Claims Analysis
Total Claims: 25
Claim 1
Independent Claim
177 words
A semiconductor laser device having little astigmatism comprising: a semiconductor substrate; semiconductor layers formed on said semiconductor substrate, including a first clad semiconductor layer, having a first band gap, a second clad semiconductor layer, having a second band gap, and an active semiconductor layer for generating layer oscillation formed between said first and second clad semiconductor layers, and having a third band gap less than said first and second band gaps; a stripe-shaped region formed in at least a portion of the semiconductor layers to define a laser cavity between a pair of semiconductor end surfaces, wherein at least one of the semiconductor end surfaces is so curved that the intersection of said one semiconductor end surface and a plane parallel to the active semiconductor layer has the form of a curved line, and the width of the stripe-shaped region in a direction perpendicular to a laser beam traveling direction and parallel to the active layer lies within a range from 1 to 10 μm; and a pair of electrodes for injecting current to said stripe-shaped region.
Claim 2
Dependent Claim
177 words
A semiconductor laser device having little astigmatism comprising: a semiconductor substrate; semiconductor layers formed on said semiconductor substrate, including a first clad semiconductor layer, having a first band gap, a second clad semiconductor layer, having a second band gap, and an active semiconductor layer for generating layer oscillation formed between said first and second clad semiconductor layers, and having a third band gap less than said first and second band gaps; a stripe-shaped region formed in at least a portion of the semiconductor layers to define a laser cavity between a pair of semiconductor end surfaces, wherein at least one of the semiconductor end surfaces is so curved that the intersection of said one semiconductor end surface and a plane parallel to the active semiconductor layer has the form of a curved line, and the width of the stripe-shaped region in a direction perpendicular to a laser beam traveling direction and parallel to the active layer lies within a range from 1 to 10 μm; and a pair of electrodes for injecting current to said stripe-shaped region.
Claim 3
Dependent Claim
31 words
A semiconductor laser device according to claim 1, wherein said curved line is a circular arc, and the radius of curvature thereof lies in a range from 10 to 300 μm.
Claim 4
Dependent Claim
24 words
A semiconductor laser device according to claim 1, wherein said width of the stripe-shaped region lies within a range from 3 to 5 μm.
Claim 5
Dependent Claim
22 words
A semiconductor laser device according to claim 1, wherein the semiconductor substrate and the semiconductor layers are made of compound semiconductor materials.
Claim 6
Dependent Claim
15 words
A semiconductor laser device according to claim 1, wherein said curved line is a parabola.
Claim 7
Dependent Claim
30 words
A semiconductor laser device according to claim 1, wherein said curved line is a circular arc, and the radius of curvature lies in a range from 10 to 300 μm.
Claim 8
Dependent Claim
31 words
A semiconductor laser device according to claim 6, wherein said curved line is a circular arc, and the radius of curvature thereof lies in a range from 20 to 50 μm.
Claim 9
Dependent Claim
18 words
A semiconductor laser device according to claim 1, wherein said curved semiconductor end surface has a convex shape.
Claim 10
Dependent Claim
18 words
A semiconductor laser device according to claim 1, wherein said curved semiconductor end surface has a concave shape.
Claim 11
Dependent Claim
34 words
A semiconductor laser device according to claim 8, wherein the width of said stripe-shaped region is smaller at said curved semiconductor end surface than at the other of said pair of semiconductor end surfaces.
Claim 12
Dependent Claim
34 words
A semiconductor laser device according to claim 9, wherein the width of said stripe-shaped region is greater at said curved semiconductor end surface than at the other of said pair of semiconductor end surfaces.
Claim 13
Dependent Claim
46 words
A semiconductor laser device according to claim 1, wherein the other of said pair of semiconductor end surfaces is so curved that the intersection of said other semiconductor end surface and a plane parallel to the active semiconductor layer has the form of a curved line.
Claim 14
Dependent Claim
18 words
A semiconductor laser device according to claim 12, wherein said one semiconductor end surface has a convex shape.
Claim 15
Dependent Claim
18 words
A semiconductor laser device according to claim 13, wherein said other semiconductor end surface has a convex shape.
Claim 16
Dependent Claim
18 words
A semiconductor laser device according to claim 13, wherein said other semiconductor end surface has a concave shape.
Claim 17
Dependent Claim
18 words
A semiconductor laser device according to claim 12, wherein said one semiconductor end surface has a concave shape.
Claim 18
Dependent Claim
18 words
A semiconductor laser device according to claim 16, wherein said other semiconductor end surface has a concave shape.
Claim 19
Dependent Claim
19 words
A semiconductor laser device according to claim 12, wherein the width of said stripe-shaped region varies along its length.
Claim 20
Dependent Claim
20 words
A semiconductor laser device according to claim 1, wherein a laser beam is emitted from said curved semiconductor end surface.
Claim 21
Dependent Claim
24 words
A semiconductor laser device according to claim 1, wherein a laser beam is emitted from the other of said pair of semiconductor end surfaces.
Claim 22
Dependent Claim
15 words
A semiconductor laser device according to claim 1, wherein said curved line is a semi-ellipse.
Claim 23
Dependent Claim
16 words
A semiconductor laser device according to claim 1, wherein said curved line is a Gaussian curve.
Claim 24
Dependent Claim
194 words
A semiconductor laser device comprising: a semiconductor substrate; semiconductor layers formed on said semiconductor substrate, including a first clad semiconductor layer, having a first band gap, a second clad semiconductor layer, having a second band gap, and an active semiconductor layer for generating layer oscillation formed between said first and second clad semiconductor layers, and having a third band gap less than said first and second band gaps; a stripe-shaped region formed in at least a portion of the semiconductor layers to define a laser cavity between a pair of semiconductor end surfaces, wherein at least one of the semiconductor end surfaces is so curved that the intersection of said one semiconductor end surface and a plane parallel to the active semiconductor layer has the form of a curved line, and the width of the stripe-shaped region in a direction perpendicular to a laser beam traveling direction and parallel to the active layer lies within a range from 1 to 10 μm, so as to enable generation of laser oscillation having a single transverse mode and a multi-longitudinal mode with little astigmatism; and a pair of electrodes for injecting current to said stripe-shaped region.
Claim 25
Dependent Claim
194 words
A semiconductor laser device comprising: a semiconductor substrate; semiconductor layers formed on said semiconductor substrate, including a first clad semiconductor layer, having a first band gap, a second clad semiconductor layer, having a second band gap, and an active semiconductor layer for generating layer oscillation formed between said first and second clad semiconductor layers, and having a third band gap less than said first and second band gaps; a stripe-shaped region formed in at least a portion of the semiconductor layers to define a laser cavity between a pair of semiconductor end surfaces, wherein at least one of the semiconductor end surfaces is so curved that the intersection of said one semiconductor end surface and a plane parallel to the active semiconductor layer has the form of a curved line, and the width of the stripe-shaped region in a direction perpendicular to a laser beam traveling direction and parallel to the active layer lies within a range from 1 to 10 μm, so as to enable generation of laser oscillation having a single transverse mode and a multi-longitudinal mode with little astigmatism; and a pair of electrodes for injecting current to said stripe-shaped region.
References Cited (Backward Citations)
No citation records indexed.
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