Patent US4904042A successfully refreshed from Google Patents.
US4904042A
Expired / Lapsed
US
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N×N optical star coupler
Assignee: Nokia Bell Labs
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Filing: 1988-05-03
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Granted: 1990-02-27
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Expires: 2008-05-03
Abstract
Abstract An efficient N×N star optical coupler suitable for mass production in integrated form is disclosed. The coupler can be realized using silicon technology to form a dielectric coupler slab and two arrays of strip waveguides all on a single glass substrate. Power transfer betwen the two arrays is accomplished through radiation in the dielectric slab with theoretical efficiency exceeding 30% under optimized conditions.
Inventors
- 👤 Corrado Dragone
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 11:23
CPC Classifications
H; H04; H04B; H04B10/00; H04B10/50; G; G02; G02B; G02B6/00; G02B6/24; G02B6/26; G02B6/28; G02B6/2804; G02B6/2808
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
232 words
A device for simultaneously transmitting optical signals representative of intelligence from N sources to N' detectors, comprising (a) a medium capable of transmitting optical radiation with loss less than 1 db/cm; (b) an array of N injection means of aperture a i for injecting, into a substantially two dimensional plane within the said medium, optical radiation; and (c) an array of N' extraction means of aperture a' i , for extracting transmitted optical radiation from the said medium; the invention characterized in that (1) the injection and extraction means comprise single mode waveguides; (2) the array of N injection means are located along a segment of a circle with radius of curvature substantially equal to R, the length, L, of the segment given substantially by L=Σa; (3) the array of N' extraction means are located along a segment of a circle of radius of curvature substantially equal to R, the length, L', of the segment given substantially by L'=Σa'; (4) the center of curvature of the circle whose segment determines the configuration of each array lies substantially on the circle segment which defines the other array; (5) the axis of symmetry of each of the elements is substantially directed to the center of curvature of the circle whose segment defines that array; and (6) the distance R is selected to substantially maximize the transmission between marginal injection elements and marginal extraction elements.
Claim 2
Independent Claim
232 words
A device for simultaneously transmitting optical signals representative of intelligence from N sources to N' detectors, comprising (a) a medium capable of transmitting optical radiation with loss less than 1 db/cm; (b) an array of N injection means of aperture a i for injecting, into a substantially two dimensional plane within the said medium, optical radiation; and (c) an array of N' extraction means of aperture a' i , for extracting transmitted optical radiation from the said medium; the invention characterized in that (1) the injection and extraction means comprise single mode waveguides; (2) the array of N injection means are located along a segment of a circle with radius of curvature substantially equal to R, the length, L, of the segment given substantially by L=Σa; (3) the array of N' extraction means are located along a segment of a circle of radius of curvature substantially equal to R, the length, L', of the segment given substantially by L'=Σa'; (4) the center of curvature of the circle whose segment determines the configuration of each array lies substantially on the circle segment which defines the other array; (5) the axis of symmetry of each of the elements is substantially directed to the center of curvature of the circle whose segment defines that array; and (6) the distance R is selected to substantially maximize the transmission between marginal injection elements and marginal extraction elements.
Claim 3
Dependent Claim
10 words
The device of claim 1 wherein the medium comprises silica.
Claim 4
Dependent Claim
11 words
The device of claim 2 wherein the medium comprises doped silica.
Claim 5
Dependent Claim
15 words
The device of claim 3 wherein the injection and extraction elements comprise doped waveguide regions.
Claim 6
Dependent Claim
39 words
The device of claim 4 further comprising means for aligning optical fibers with the doped waveguide regions such that the axis of symmetry of each doped waveguide region substantially coincides with an axis of symmetry of an optical fiber.
Claim 7
Dependent Claim
11 words
The device of claim 5 wherein the alignment means comprise grooves.
Claim 8
Dependent Claim
23 words
The device of claim 6 wherein the apertures of the individual elements are selected to substantially equalize transmission to each of the elements.
Claim 9
Dependent Claim
21 words
The device of claim 6 wherein the width of the doped waveguide regions increases as the waveguiding portion approaches the medium.
Claim 10
Independent Claim
18 words
The device of claims 1 or 4 wherein the array of injection and extraction means is three dimensional.
References Cited (Backward Citations)
US4474425A
Cited
US4786131A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-02-26 | 1993-08-28 | 1994-02-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-02-26 | 1997-08-28 | 1998-02-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-02-26 | 2001-08-28 | 2002-02-27 | $7700.00 | Window Closed / Lapsed |