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US5013115A
Expired / Lapsed
US
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Polarization insensitive optical frequency mixer
Assignee: British Telecommunications PLC
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Filing: 1989-02-15
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Granted: 1991-05-07
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Expires: 2009-02-15
Abstract
Abstract A polarisation insensitive optical frequency mixer comprising an optical fibre coupler block (2) a silica fibre (6) with a region whose cladding (4) has been polished off close to the core (8) on which is rotatably mounted interdigitated electrodes (12) spaced from the coupler block (2) by a polymer film spacer (12). The electrodes (12) induce a spatially periodic electric field within the core (4) which reverses every half period which provides frequency doubling of light passing through the fibre (6) over the whole grating length. The electrodes are dimensioned to provide polarisation insensitised frequency mixing by providing that the electric field components within the optical waveguide are substantially equal in two mutually orthogonal directions transverse the waveguide.
Inventors
- 👤 Raman Kashyap
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 19:11
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/35; G02F1/353; G02F1/3544; G02F1/37; G02F1/377; G02F1/3546
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
93 words
A polarisation insensitive optical frequency mixer for generating a harmonic of a light signal comprising an optical waveguide; and a pair of interdigitated electrodes located on one side of the waveguide for producing within the waveguide a spatially periodic electric field having a reversal every half period; the period being selected to phasematch the interacting frequencies each with its own mode with the light signal and the electrode dimensions being selected to provide that the electric field within the optical waveguide is substantially equal in two mutually orthogonal directions transverse to the waveguide.
Claim 2
Dependent Claim
93 words
A polarisation insensitive optical frequency mixer for generating a harmonic of a light signal comprising an optical waveguide; and a pair of interdigitated electrodes located on one side of the waveguide for producing within the waveguide a spatially periodic electric field having a reversal every half period; the period being selected to phasematch the interacting frequencies each with its own mode with the light signal and the electrode dimensions being selected to provide that the electric field within the optical waveguide is substantially equal in two mutually orthogonal directions transverse to the waveguide.
Claim 3
Dependent Claim
102 words
A polarization insensitive optical frequency mixer for generating a harmonic of a light signal comprising: an optical waveguide; and a pair of interdigitated electrodes located on one side of the waveguide for producing within the waveguide a spatially periodic electric field having a reversal every half period, said electrodes being rotatable relative to said optical waveguide; the period being selected to phasematch the interacting frequencies each with its own mode with the light signal and the electrode dimensions being selected to provide that the electric field within the optical waveguide is substantially equal in two mutually orthogonal directions transverse to the waveguide.
Claim 4
Dependent Claim
102 words
A polarization insensitive optical frequency mixer for generating a harmonic of a light signal comprising: an optical waveguide; and a pair of interdigitated electrodes located on one side of the waveguide for producing within the waveguide a spatially periodic electric field having a reversal every half period, said electrodes being rotatable relative to said optical waveguide; the period being selected to phasematch the interacting frequencies each with its own mode with the light signal and the electrode dimensions being selected to provide that the electric field within the optical waveguide is substantially equal in two mutually orthogonal directions transverse to the waveguide.
Claim 5
Dependent Claim
37 words
An optical frequency mixer as claimed in claim 1 in which said electrodes diverge along an axis and are moveable relative to the waveguide thereby to change the spatial periodicity of the electrodes relative to the waveguide.
Claim 6
Dependent Claim
24 words
An optical frequency mixer as claimed in claim 1 in which said optical waveguide comprises an optical fibre coupler block incorporating a silica fibre.
Claim 7
Dependent Claim
41 words
An optical frequency mixer as claimed in claim 1 in which said electrodes are formed on a glass slide and separated from the optical waveguide by a spacer of a medium of lower refractive index than the cladding of the waveguide.
Claim 8
Dependent Claim
74 words
A polarization insensitive optical frequency mixer for generating a harmonic of a light signal comprising: an optical waveguide, and interdigitated electrodes adjacent the waveguide generating a spatially periodic electric field within the waveguide that reverses at half periods, said field being substantially equal in two orthogonal directions transverse to said waveguide; the period of said field being selected to phasematch interacting frequencies of said light signal each corresponding to a mode of the waveguide.
Claim 9
Dependent Claim
74 words
A polarization insensitive optical frequency mixer for generating a harmonic of a light signal comprising: an optical waveguide, and interdigitated electrodes adjacent the waveguide generating a spatially periodic electric field within the waveguide that reverses at half periods, said field being substantially equal in two orthogonal directions transverse to said waveguide; the period of said field being selected to phasematch interacting frequencies of said light signal each corresponding to a mode of the waveguide.
Claim 10
Dependent Claim
18 words
An optical frequency mixer as in claim 6 in which said electrodes are rotatable relative to said waveguide.
Claim 11
Dependent Claim
28 words
An optical frequency mixer as in claim 6 in which said electrodes diverge and are moveable relative to said waveguide to adjust the spatial periodicity of said field.
Claim 12
Independent Claim
112 words
A method for genrating a harmonic of a light signal using a polarization insensitive optical frequency mixer comprising a waveguide and interdigitated electrodes adjacent the waveguide, said method comprising the steps of: a. launching an optical signal through the waveguide, b. applying a periodic electric current to the electrodes to generate a spatially periodic electric field in the waveguide that reverse at half periods, c. orienting the electrodes so that the electric field is substantially equal in two orthogonal directions transverse to the waveguide, and d. selecting the period of the spatially periodic electric field to phasematch interacting frequencies of the light signal that each correspond to a mode of the waveguide.
Claim 13
Independent Claim
112 words
A method for genrating a harmonic of a light signal using a polarization insensitive optical frequency mixer comprising a waveguide and interdigitated electrodes adjacent the waveguide, said method comprising the steps of: a. launching an optical signal through the waveguide, b. applying a periodic electric current to the electrodes to generate a spatially periodic electric field in the waveguide that reverse at half periods, c. orienting the electrodes so that the electric field is substantially equal in two orthogonal directions transverse to the waveguide, and d. selecting the period of the spatially periodic electric field to phasematch interacting frequencies of the light signal that each correspond to a mode of the waveguide.
Claim 14
Dependent Claim
17 words
A method as claim 9 wherein said orienting step comprises rotating the electrodes relative to the waveguide.
References Cited (Backward Citations)
FR2385114A1
Cited
US4684215A
Cited
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| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
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| 3.5 Years (Year 4) | 1994-05-06 | 1994-11-05 | 1995-05-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-05-06 | 1998-11-05 | 1999-05-07 | $3760.00 | Window Closed / Lapsed |
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