US4932032A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Tapered semiconductor waveguides
Assignee: Nokia Bell Labs
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Filing: 1989-08-03
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Granted: 1990-06-05
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Expires: 2009-08-03
Abstract
Abstract Adiabatic mode control and structural reproducibility are achieved by a tapered semiconductor waveguide structure wherein semiconductor guiding layers are interleaved with stop-etch layers and each successive guiding layer extends further along the propagation axis of the waveguide than the guiding layer immediately adjacent thereabove to create a staircase-like core or guiding structure. Cladding regions of appropriate semiconductor material having a lower index of refraction than the tapered core structure may be added to completely surround the tapered guiding structure. The profile of the tapered structure is realizable as any desired staircase-like shape such as linear, parabolic, exponential or the like. Additional layers of higher index of refraction semiconductor material may be included in the cladding region to permit additional beam shaping of the expanded spatial mode propagating along the tapered waveguide.
Inventors
- 👤 Thomas L. Koch
- 👤 Uziel Koren
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 06:03
CPC Classifications
G; G02; G02B; G02B6/00; G02B6/24; G02B6/26; G02B6/30; G02B6/305; G02B6/10; G02B6/12; G02B6/122; G02B6/1228; H; H01; H01S; H01S5/00; H01S5/10; H01S5/1028; H01S5/1032; H01S5/1003; H01S5/1014; H01S5/30; H01S5/32; H01S5/323; H01S5/3235; H01S5/32391
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
76 words
A tapered waveguide having a propagation axis and a reference plane defined normal to said propagation axis, wherein the tapered waveguide comprises a plurality of guiding layers including a first semiconductor material, and a plurality of stop-etch layers arranged including a second semiconductor material, said stop-etch layers arranged alternately with said guiding layers, and each guiding layer arranged to extend from said reference plane along said propagation axis further than said guiding layer immediately adjacent thereabove.
Claim 2
Dependent Claim
76 words
A tapered waveguide having a propagation axis and a reference plane defined normal to said propagation axis, wherein the tapered waveguide comprises a plurality of guiding layers including a first semiconductor material, and a plurality of stop-etch layers arranged including a second semiconductor material, said stop-etch layers arranged alternately with said guiding layers, and each guiding layer arranged to extend from said reference plane along said propagation axis further than said guiding layer immediately adjacent thereabove.
Claim 3
Dependent Claim
53 words
The tapered waveguide defined in claim 1 further including a cladding region substantially surrounding exterior surfaces of said pluralities of guiding and stop-etch layers, said cladding region comprising third semiconductor material, said first semiconductor material having an index of refraction which is greater than an index of refraction for said third semiconductor material.
Claim 4
Dependent Claim
29 words
The tapered waveguide defined in claim 2 wherein said first, second and third semiconductor materials are selected from the group consisting of Group III-V compositions and Group II-VI compositions.
Claim 5
Dependent Claim
23 words
The tapered waveguide defined in claim 2 wherein said first semiconductor material includes InGaAsP, and said second and third semiconductor materials include InP.
Claim 6
Dependent Claim
43 words
The tapered waveguide defined in claim 1 wherein each guiding layer of said plurality extends along the propagation axis sufficiently far for said plurality of guiding layers to exhibit a staircase-like profile selected from the group consisting of linear, parabolic and exponential profiles.
Claim 7
Dependent Claim
138 words
A tapered waveguide having a propagation axis and a reference plane defined normal to said propagation axis, wherein the tapered waveguide comprises a plurality of guiding layers including a first semiconductor material, and a plurality of stop-etch layers including a second semiconductor material, said stop-etch layers arranged alternately with said guiding layers, and each guiding layer arranged to extend from said reference plane along said propagation axis further than said guiding layer immediately adjacent thereabove, a cladding region substantially surrounding exterior surfaces of said pluralities of guiding and stop-etch layers, said cladding region comprising third semiconductor material, said first semiconductor material having an index of refraction which is greater than an index of refraction for said third semiconductor material, said cladding region further including means for controlling a predetermined characteristic of lightwave signals propagating along said tapered waveguide.
Claim 8
Dependent Claim
138 words
A tapered waveguide having a propagation axis and a reference plane defined normal to said propagation axis, wherein the tapered waveguide comprises a plurality of guiding layers including a first semiconductor material, and a plurality of stop-etch layers including a second semiconductor material, said stop-etch layers arranged alternately with said guiding layers, and each guiding layer arranged to extend from said reference plane along said propagation axis further than said guiding layer immediately adjacent thereabove, a cladding region substantially surrounding exterior surfaces of said pluralities of guiding and stop-etch layers, said cladding region comprising third semiconductor material, said first semiconductor material having an index of refraction which is greater than an index of refraction for said third semiconductor material, said cladding region further including means for controlling a predetermined characteristic of lightwave signals propagating along said tapered waveguide.
Claim 9
Dependent Claim
54 words
The tapered waveguide defined in claim 6 wherein said controlling means comprises at least a first beam control layer including a fourth semiconductor material having an index of refraction greater than said index of refraction for said third semiconductor material, said first beam control layer being disposed parallel to said plurality of guiding layers.
Claim 10
Dependent Claim
28 words
The tapered waveguide defined in claim 7 wherein said first through fourth semiconductor materials are selected from the group consisting of Group III-V compositions and Group II-VI compositions.
Claim 11
Dependent Claim
70 words
The tapered waveguide defined in claim 7 wherein said controlling means further comprises a second beam control layer including a fifth semiconductor material having an index of refraction greater than said index of refraction for said third semiconductor material, said second beam control layer being disposed parallel to said plurality of guiding layers and on an opposite side of said plurality of guiding layers from said first beam control layer.
Claim 12
Dependent Claim
28 words
The tapered waveguide defined in claim 9 wherein said first through fifth semiconductor materials are selected from the group consisting of Group III-V compositions and Group II-VI compositions.
Claim 13
Dependent Claim
45 words
The tapered waveguide defined in claims 8 or 10 wherein each guiding layer of said plurality extends along the propagation axis sufficiently far for said plurality of guiding layers to exhibit a staircase-like profile selected from the group consisting of linear, parabolic and exponential profiles.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-06-04 | 1993-12-04 | 1994-06-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-06-04 | 1997-12-04 | 1998-06-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-06-04 | 2001-12-04 | 2002-06-05 | $7700.00 | Window Closed / Lapsed |