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Distributed coupler switch

Assignee: Oki Electric Industry Co Ltd
•
Filing: 1988-11-18
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Granted: 1989-12-05
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Expires: 2008-11-18
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Abstract

Abstract In an electro-optic distributed coupler switch having a parallel rib geometry, a coupling enhancement region formed of the same material as the upper cladding layers but of lower step height is located between the ribs. By increasing the electric field strength, the coupling enhancement region enables the coupling length L c to be reduced.

Inventors

  • 👤 Takashi Ushikubo
  • 👤 Hideaki Okayama
  • 👤 Masato Kawahara
  • 👤 Issei Asabayashi

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-08 04:47
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/29; G02F1/31; G02F1/313; G02F1/3132; G02F1/3133; G02F2201/00; G02F2201/06; G02F2201/063

Claims Analysis

Total Claims: 15
Claim 1
Independent Claim 124 words
A distributed coupler switch comprising: a substrate: a lower cladding layer disposed on said substrate; a light-guide layer disposed on said lower cladding layer; and a pair of parallel stripe-geometry upper cladding layers disposed on said light-guide layer; each of said layers being composed of compound semiconductor materials; said switch further comprising a coupling enhancement region disposed on said light-guide layer and extending between said upper cladding layers, said coupling enhancement region being made of the same material as said upper cladding layers but being lower than them in step height; said light-guide layer, in a region outside said upper cladding layers, having no layer thereon which is composed of a material which is the same as the material composing said coupling enhancement region.
Claim 2
Dependent Claim 124 words
A distributed coupler switch comprising: a substrate: a lower cladding layer disposed on said substrate; a light-guide layer disposed on said lower cladding layer; and a pair of parallel stripe-geometry upper cladding layers disposed on said light-guide layer; each of said layers being composed of compound semiconductor materials; said switch further comprising a coupling enhancement region disposed on said light-guide layer and extending between said upper cladding layers, said coupling enhancement region being made of the same material as said upper cladding layers but being lower than them in step height; said light-guide layer, in a region outside said upper cladding layers, having no layer thereon which is composed of a material which is the same as the material composing said coupling enhancement region.
Claim 3
Dependent Claim 30 words
A distributed coupler switch according to claim 1, wherein said lower cladding layer comprises an n-type compound semiconductor material and said upper cladding layer comprises a p-type compound semiconductor material.
Claim 4
Dependent Claim 37 words
A distributed coupler switch according to claim 2, wherein said lower cladding layer is an n-Al 0 .3 Ga 0 .7 As layer and said upper cladding layers are p-Al 0 .3 Ga 0 .7 As layers.
Claim 5
Dependent Claim 30 words
A distributed coupler switch according to claim 1, wherein said lower cladding layer comprises an p-type compound semiconductor material and said upper cladding layer comprises a n-type compound semiconductor material.
Claim 6
Dependent Claim 37 words
A distributed coupler switch according to claim 4, wherein said lower cladding layer is a p-Al 0 .3 Ga 0 .7 As layer and said upper cladding layers are n-Al 0 .3 Ga 0 .7 As layers.
Claim 7
Dependent Claim 16 words
A distributed coupler switch according to claim 1, wherein said light-guide layer comprises an i-GaAs material.
Claim 8
Dependent Claim 26 words
A distributed coupler switch according to claim 1, wherein those regions of said light-guide layer disposed directly below said upper cladding layers operate as optical waveguides.
Claim 9
Dependent Claim 30 words
A distributed coupler switch according to claim 1, wherein said upper cladding layers comprise Al 0 .3 Ga 0 .7 As material, and said light-guide layer comprises an i-GaAs material.
Claim 10
Dependent Claim 22 words
A distributed coupler switch according to claim 8, wherein said lower cladding layer comprises Al 0 .3 Ga 0 .7 As material.
Claim 11
Dependent Claim 30 words
A distributed coupler switch according to claim 9, wherein said upper cladding layer is of a first conductivity type, and said lower cladding layer is of a second conductivity type.
Claim 12
Dependent Claim 34 words
A distributed coupler switch according to claim 10, wherein said upper cladding layers are p-Al 0 .3 Ga 0 .7 As, and said lower cladding layer is n-Al 0 .3 Ga 0 .7 As.
Claim 13
Dependent Claim 34 words
A distributed coupler switch according to claim 10, wherein said upper cladding layers are n-Al 0 .3 Ga 0 .7 As, and said lower cladding layer is p-Al 0 .3 Ga 0 .7 As.
Claim 14
Dependent Claim 186 words
A distributed coupler switch comprising: a substrate: a lower cladding layer disposed on said substrate; a light-guide layer disposed on said lower cladding layer; and a pair of parallel stripe-geometry upper cladding layers disposed on said light-guide layer; each of said layers being composed of compound semiconductor materials; said switch further comprising first and second electrodes for applying an electric field to said light-guide layer and said pair of upper cladding layers, and a coupling enhancement region disposed on said light-guide layer and extending only between said upper cladding layers, said coupling enhancement region being made of the same material as said upper cladding layers but being lower than them in step height; whereby said coupling enhancement region causes the equivalent index of refraction in said light guide layer beneath said coupling enhancement region to be different than the equivalent index of refraction in said light-guide layer in regions which are disposed on either outward side of and which extend away from said upper cladding layers, whereby application of an electric field causes enhanced electric field coupling between said pair of parallel stripe-geometry upper cladding layers.
Claim 15
Dependent Claim 186 words
A distributed coupler switch comprising: a substrate: a lower cladding layer disposed on said substrate; a light-guide layer disposed on said lower cladding layer; and a pair of parallel stripe-geometry upper cladding layers disposed on said light-guide layer; each of said layers being composed of compound semiconductor materials; said switch further comprising first and second electrodes for applying an electric field to said light-guide layer and said pair of upper cladding layers, and a coupling enhancement region disposed on said light-guide layer and extending only between said upper cladding layers, said coupling enhancement region being made of the same material as said upper cladding layers but being lower than them in step height; whereby said coupling enhancement region causes the equivalent index of refraction in said light guide layer beneath said coupling enhancement region to be different than the equivalent index of refraction in said light-guide layer in regions which are disposed on either outward side of and which extend away from said upper cladding layers, whereby application of an electric field causes enhanced electric field coupling between said pair of parallel stripe-geometry upper cladding layers.

References Cited (Backward Citations)

US4693543A Cited
US4737003A Cited
US4795225A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1992-12-04 1993-06-05 1993-12-05 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1996-12-04 1997-06-05 1997-12-05 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 2000-12-04 2001-06-05 2001-12-05 $7700.00 Window Closed / Lapsed

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