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Electrooptic polarization multiplexer/demultiplexer

Assignee: Nokia Bell Labs
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Filing: 1984-05-29
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Granted: 1987-12-08
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Expires: 2004-05-29
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Abstract

Abstract An electrooptic polarization multiplexer/demultiplexer incorporates an electrooptic, directional coupler switch structure. The multiplexer/demultiplexer includes a substrate of birefringent, electrooptic material, a pair of phase matched, dielectric waveguides embedded in the substrate and spaced closely together over a distance L (the coupler or device length), a buffer layer of insulating material positioned over the substrate and the pair of electrodes, and a plurality of metallic electrodes positioned on the buffer layer in the vicinity of the waveguides. Electrodes are arranged in a multi-section, reversed Δβ configuration. The distance L is selected such that 1≦L/1 TE ≦2 and L/1 TM ≦0.5, where 1 TE and 1 TM are transfer lengths for the TE and TM modes, respectively.

Inventors

  • 👤 Rodney C. Alferness

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-28 12:38
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/29; G02F1/31; G02F1/313; G02F1/3132; H; H04; H04J; H04J14/00; H04J14/06; G02F1/01; G02F1/0136; G02F1/0144; G02F2201/00; G02F2201/12; G02F2201/125

Claims Analysis

Total Claims: 12
Claim 1
Independent Claim 153 words
A polarization sensitive switching device including a substrate of birefringent, electrooptic material, a first and second dielectric waveguide embedded in said substrate and closely spaced together over a distance L, at least first and second metallic electrodes, said first and second electrode extending for said distance L in the vicinity of said first and second waveguides, respectively, said second electrode including at least first and second portions electrically disconnected from each other and having respective lengths substantially equal to L/2, and a buffer layer of insulating material intermediate to the electrodes and both the substrate and waveguides, the device characterized in that the first and second waveguides are substantially phase matched to each other for similarly polarized modes of an input optical signal, and said distance L is such that 1≦L/1 TE ≦2 and L/1 TM ≦0.5, where 1 TE and 1 TM are transfer lengths for the TE and TM modes, respectively.
Claim 2
Dependent Claim 153 words
A polarization sensitive switching device including a substrate of birefringent, electrooptic material, a first and second dielectric waveguide embedded in said substrate and closely spaced together over a distance L, at least first and second metallic electrodes, said first and second electrode extending for said distance L in the vicinity of said first and second waveguides, respectively, said second electrode including at least first and second portions electrically disconnected from each other and having respective lengths substantially equal to L/2, and a buffer layer of insulating material intermediate to the electrodes and both the substrate and waveguides, the device characterized in that the first and second waveguides are substantially phase matched to each other for similarly polarized modes of an input optical signal, and said distance L is such that 1≦L/1 TE ≦2 and L/1 TM ≦0.5, where 1 TE and 1 TM are transfer lengths for the TE and TM modes, respectively.
Claim 3
Dependent Claim 34 words
The device defined in claim 1 further characterized in that the difference for propagation constants of the first and second waveguides is substantially equal to zero for each polarization of the input optical signal.
Claim 4
Dependent Claim 155 words
A polarization sensitive switching device including a substrate of birefringent, electrooptic material, a first and second dielectric waveguide embedded in said substrate and closely spaced together over a distance L, at least first and second metallic electrodes, said first and second electrode extending for said distance L in the vicinity of said first and second waveguides, respectively, said second electrode including at least first and second portions being electrically disconnected from each other and having respective lengths substantially equal to L/2, and a buffer layer of insulating material intermediate to the electrodes and both the substrate and waveguides, the device characterized in that the first and second waveguides are substantially phase matched to each other for similar polarizations of an input optical signal, and said distance L is such that L/1 TE ≧1 and L/1 TM ≦L/1 TE /2, where 1 TE and 1 TM are transfer lengths for the TE and TM modes, respectively.
Claim 5
Dependent Claim 155 words
A polarization sensitive switching device including a substrate of birefringent, electrooptic material, a first and second dielectric waveguide embedded in said substrate and closely spaced together over a distance L, at least first and second metallic electrodes, said first and second electrode extending for said distance L in the vicinity of said first and second waveguides, respectively, said second electrode including at least first and second portions being electrically disconnected from each other and having respective lengths substantially equal to L/2, and a buffer layer of insulating material intermediate to the electrodes and both the substrate and waveguides, the device characterized in that the first and second waveguides are substantially phase matched to each other for similar polarizations of an input optical signal, and said distance L is such that L/1 TE ≧1 and L/1 TM ≦L/1 TE /2, where 1 TE and 1 TM are transfer lengths for the TE and TM modes, respectively.
Claim 6
Dependent Claim 34 words
The device defined in claim 3 further characterized in that the difference for propagation constants of the first and second waveguides is substantially equal to zero for each polarization of the input optical signal.
Claim 7
Dependent Claim 128 words
An electrooptic device including a directional coupler switch having a substrate of birefringent material, a pair of dielectric waveguides embedded in said substrate and spaced closely together over a distance L, a buffer layer positioned over said substrate and said pair of electrodes, and a plurality of electrodes positioned on the buffer layer in the vicinity of said waveguides, said electrodes being arranged in at least a two-section, reversed Δβ configuration, the device being characterized in that, the pair of waveguides are substantially phase matched to each other for similar polarizations of an input optical signal, and said distance L is such that L/1 TE ≧1 and L/1 TM ≦L/1 TE /2, where 1 TE and 1 TM are transfer lengths for the TE and TM modes, respectively.
Claim 8
Dependent Claim 128 words
An electrooptic device including a directional coupler switch having a substrate of birefringent material, a pair of dielectric waveguides embedded in said substrate and spaced closely together over a distance L, a buffer layer positioned over said substrate and said pair of electrodes, and a plurality of electrodes positioned on the buffer layer in the vicinity of said waveguides, said electrodes being arranged in at least a two-section, reversed Δβ configuration, the device being characterized in that, the pair of waveguides are substantially phase matched to each other for similar polarizations of an input optical signal, and said distance L is such that L/1 TE ≧1 and L/1 TM ≦L/1 TE /2, where 1 TE and 1 TM are transfer lengths for the TE and TM modes, respectively.
Claim 9
Dependent Claim 33 words
The device defined in claim 5 further characterized in that the difference for propagation constants of the pair of waveguides is substantially equal to zero for each polarization of the input optical signal.
Claim 10
Dependent Claim 126 words
An electrooptic device including a directional coupler switch having a substrate of birefringent material, a pair of dielectric waveguides embedded in said substrate and spaced closely together over a distance L, a buffer layer positioned over said substrate and said pair of electrodes, and a plurality of electrodes positioned on the buffer layer in the vicinity of said waveguides, said electrodes being arranged in at least a two-section, reversed Δβ configuration, the device being characterized in that, the pair of waveguides are substantially phase matched to each other for similar polarizations of an input optical signal, and said distance L is such that 1≦L/1 TE ≦2 and L/1 TM ≦0.5, where 1 TE and 1 TM are transfer lengths for the TE and TM modes, respectively.
Claim 11
Dependent Claim 126 words
An electrooptic device including a directional coupler switch having a substrate of birefringent material, a pair of dielectric waveguides embedded in said substrate and spaced closely together over a distance L, a buffer layer positioned over said substrate and said pair of electrodes, and a plurality of electrodes positioned on the buffer layer in the vicinity of said waveguides, said electrodes being arranged in at least a two-section, reversed Δβ configuration, the device being characterized in that, the pair of waveguides are substantially phase matched to each other for similar polarizations of an input optical signal, and said distance L is such that 1≦L/1 TE ≦2 and L/1 TM ≦0.5, where 1 TE and 1 TM are transfer lengths for the TE and TM modes, respectively.
Claim 12
Dependent Claim 33 words
The device defined in claim 7 further characterized in that the difference for propagation constants of the pair of waveguides is substantially equal to zero for each polarization of the input optical signal.

References Cited (Backward Citations)

US4243295A Cited
US4262993A Cited
US4390236A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1990-12-07 1991-06-08 1991-12-08 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1994-12-07 1995-06-08 1995-12-08 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1998-12-07 1999-06-08 1999-12-08 $7700.00 Window Closed / Lapsed

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