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US5375180A
Expired / Lapsed
US
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Process tolerant reverse delta-beta directional coupler switch and method of fabricating same
Assignee: AT&T Inc
•
Filing: 1993-10-04
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Granted: 1994-12-20
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Expires: 2013-10-04
Abstract
Abstract A three or more section reverse DELTA beta directional coupler designed to operate at a number of coupling lengths (L/l) selected from a region of a corresponding switching diagram where the cross and bar state switching curves are approximately parallel to each other and to the vertical axis, the vertical axis defining numbers of coupling lengths, or from a region of corresponding process sensitivity plots for the cross and bar states where the cross and bar state voltage curves are both approximately of zero slope. A number of these directional couplers form an optical switching array and a number of arrays form a system or network for switching optical signals each of which are capable of operation with uniform cross and bar state voltages at low crosstalk levels.
Inventors
- 👤 Edmond J. Murphy
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 22:04
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/29; G02F1/31; G02F1/313; G02F1/3132; G02F1/01; G02F1/21; G02F1/225; G02F2201/00; G02F2201/12; G02F2201/125
Claims Analysis
Total Claims: 88
Claim 1
Independent Claim
165 words
An optical waveguide switch comprising: first and second optical waveguides formed in or on a substrate of electro-optic material, said first and second optical waveguides being closely disposed to each other in a coupling region having a number of coupling lengths selected from a corresponding switching diagram having cross and bar state switching curves, said switching diagram having a first axis corresponding to numbers of coupling lengths and a second axis proportional to cross and bar state voltages, said number of coupling lengths selected from a region of the switching diagram where the cross and bar state switching curves are approximately in parallel with each other and with the first axis of the switching diagram corresponding to the numbers of coupling lengths, and at least three pairs of reverse Δβ electrodes in the coupling region for switching said first and second optical waveguides to a cross state in response to a cross state voltage and a bar state in response to a bar state voltage.
Claim 2
Dependent Claim
165 words
An optical waveguide switch comprising: first and second optical waveguides formed in or on a substrate of electro-optic material, said first and second optical waveguides being closely disposed to each other in a coupling region having a number of coupling lengths selected from a corresponding switching diagram having cross and bar state switching curves, said switching diagram having a first axis corresponding to numbers of coupling lengths and a second axis proportional to cross and bar state voltages, said number of coupling lengths selected from a region of the switching diagram where the cross and bar state switching curves are approximately in parallel with each other and with the first axis of the switching diagram corresponding to the numbers of coupling lengths, and at least three pairs of reverse Δβ electrodes in the coupling region for switching said first and second optical waveguides to a cross state in response to a cross state voltage and a bar state in response to a bar state voltage.
Claim 3
Dependent Claim
14 words
The optical switch of claim 1, wherein the substrate is formed from lithium niobate.
Claim 4
Dependent Claim
17 words
The optical switch of claim 2, wherein the waveguides are formed in the substrate by titanium diffusion.
Claim 5
Dependent Claim
16 words
The optical switch of claim 1, wherein the waveguides are in parallel in the coupling region.
Claim 6
Dependent Claim
26 words
The optical switch of claim 1, wherein the electrodes are formed on an upper surface of the substrate using suitable thin film deposition techniques and photolithography.
Claim 7
Dependent Claim
26 words
The optical switch of claim 1, wherein the electrodes are formed on a dielectric film on the substrate using suitable thin film deposition techniques and photolithography.
Claim 8
Dependent Claim
14 words
The optical switch of claim 6, wherein the dielectric film is SiO 2 .
Claim 9
Dependent Claim
26 words
The optical switch of claim 1, wherein the electrodes are of equal length, are equally spaced, and are aligned to the waveguides in the coupling region.
Claim 10
Dependent Claim
17 words
The optical switch of claim 1, wherein the optical switch is a three-section reverse Δβ directional coupler.
Claim 11
Dependent Claim
15 words
The optical switch of claim 9, wherein the number of coupling lengths is approximately 3.
Claim 12
Dependent Claim
103 words
The optical switch of claim 10, wherein there are three pairs of reverse Δβ electrodes, a first, second, and third pair, each pair comprising first and second electrodes, the second electrode of each pair integrally formed as a center electrode, said center electrode moving from a position covering said second waveguide and in operable alignment with said first electrode of said first pair to a second position covering said first waveguide and in operable alignment with said first electrode of said second pair and to a position covering said second waveguide and in operable alignment with said first electrode of said third pair.
Claim 13
Dependent Claim
16 words
The optical switch of claim 1, wherein the optical switch is a one-input/one-output coupled waveguide interferometer.
Claim 14
Dependent Claim
16 words
The optical switch of claim 1, wherein the optical switch is a polarization independent directional coupler.
Claim 15
Dependent Claim
119 words
An optical waveguide switch comprising: first and second optical waveguides formed in or on a substrate of electro-optic material, said first and second optical waveguides being closely disposed to each other in a coupling region having a number of coupling lengths, said number of coupling lengths selected from a region of corresponding process sensitivity plots, having cross and bar state voltage curves, where the cross and bar state voltage curves are both of approximately zero slope, and at least three pairs of reverse Δβ electrodes in the coupling region for switching said first and second optical waveguides to a cross state in response to a cross state voltage and a bar state in response to a bar state voltage.
Claim 16
Dependent Claim
119 words
An optical waveguide switch comprising: first and second optical waveguides formed in or on a substrate of electro-optic material, said first and second optical waveguides being closely disposed to each other in a coupling region having a number of coupling lengths, said number of coupling lengths selected from a region of corresponding process sensitivity plots, having cross and bar state voltage curves, where the cross and bar state voltage curves are both of approximately zero slope, and at least three pairs of reverse Δβ electrodes in the coupling region for switching said first and second optical waveguides to a cross state in response to a cross state voltage and a bar state in response to a bar state voltage.
Claim 17
Dependent Claim
14 words
The optical switch of claim 14, wherein the substrate is formed from lithium niobate.
Claim 18
Dependent Claim
17 words
The optical switch of claim 15, wherein the waveguides are formed in the substrate by titanium diffusion.
Claim 19
Dependent Claim
16 words
The optical switch of claim 14, wherein the waveguides are in parallel in the coupling region.
Claim 20
Dependent Claim
26 words
The optical switch of claim 14, wherein the electrodes are formed on the upper surface of the substrate using suitable thin film deposition techniques and photolithography.
Claim 21
Dependent Claim
26 words
The optical switch of claim 14, wherein the electrodes are formed on a dielectric film on the substrate using suitable thin film deposition techniques and photolithography.
Claim 22
Dependent Claim
14 words
The optical switch of claim 19, wherein the dielectric film is SiO 2 .
Claim 23
Dependent Claim
26 words
The optical switch of claim 14, wherein the electrodes are of equal length, are equally spaced, and are aligned to the waveguides in the coupling region.
Claim 24
Dependent Claim
17 words
The optical switch of claim 14, wherein the optical switch is a three-section reverse Δβ directional coupler.
Claim 25
Dependent Claim
15 words
The optical switch of claim 22, wherein the number of coupling lengths is approximately 3.
Claim 26
Dependent Claim
103 words
The optical switch of claim 23, wherein there are three pairs of reverse Δβ electrodes, a first, second, and third pair, each pair comprising first and second electrodes, the second electrode of each pair integrally formed as a center electrode, said center electrode moving from a position covering said second waveguide and in operable alignment with said first electrode of said first pair to a second position covering said first waveguide and in operable alignment with said first electrode of said second pair and to a position covering said second waveguide and in operable alignment with said first electrode of said third pair.
Claim 27
Dependent Claim
16 words
The optical switch of claim 14, wherein the optical switch is a one-input/one-output coupled waveguide interferometer.
Claim 28
Dependent Claim
15 words
The optical switch of claim 14, wherein the optical switch is a polarization independent coupler.
Claim 29
Dependent Claim
137 words
An optical waveguide switch comprising: means for propagating an optical signal from one or more inputs to one or more outputs having a coupling region of a number of coupling lengths selected from a corresponding switching diagram having cross and bar state switching curves, said switching diagram having a first axis corresponding to numbers of coupling lengths and a second axis proportional to cross and bar state voltages, said number of coupling lengths selected from a region of the switching diagram where said cross and bar state switching curves are approximately in parallel with each other and with the first axis of the switching diagram corresponding to the numbers of coupling lengths, and means for coupling said optical signal between each of said one or more inputs and outputs in response to cross and bar state voltages.
Claim 30
Dependent Claim
137 words
An optical waveguide switch comprising: means for propagating an optical signal from one or more inputs to one or more outputs having a coupling region of a number of coupling lengths selected from a corresponding switching diagram having cross and bar state switching curves, said switching diagram having a first axis corresponding to numbers of coupling lengths and a second axis proportional to cross and bar state voltages, said number of coupling lengths selected from a region of the switching diagram where said cross and bar state switching curves are approximately in parallel with each other and with the first axis of the switching diagram corresponding to the numbers of coupling lengths, and means for coupling said optical signal between each of said one or more inputs and outputs in response to cross and bar state voltages.
Claim 31
Dependent Claim
48 words
The optical switch of claim 27, wherein the means for propagating an optical signal includes first and second optical waveguides formed by titanium diffusion in a substrate of lithium niobate, said first and second optical waveguides in parallel and closely disposed to each other in said coupling region.
Claim 32
Dependent Claim
54 words
The optical switch of claim 27, wherein the means for coupling includes at least three pairs of reverse Δβ electrodes in the coupling region for switching said first and second optical waveguides to a cross state in response to a cross state voltage and a bar state in response to a bar state voltage.
Claim 33
Dependent Claim
17 words
The optical switch of claim 27, wherein said optical switch is a three-section reverse Δβ directional coupler.
Claim 34
Dependent Claim
15 words
The optical switch of claim 30, wherein the number of coupling lengths is approximately 3.
Claim 35
Dependent Claim
90 words
An optical switch comprising: means for propagating an optical signal from one or more inputs to one or more outputs having a coupling region of a number of coupling lengths, said number of coupling lengths selected from a region of corresponding process sensitivity plots, having cross and bar state voltage curves, where the cross and bar state voltage curves are both of approximately zero slope, and means for coupling said optical signal between each of said one or more inputs and outputs in response to cross and bar state voltages.
Claim 36
Dependent Claim
90 words
An optical switch comprising: means for propagating an optical signal from one or more inputs to one or more outputs having a coupling region of a number of coupling lengths, said number of coupling lengths selected from a region of corresponding process sensitivity plots, having cross and bar state voltage curves, where the cross and bar state voltage curves are both of approximately zero slope, and means for coupling said optical signal between each of said one or more inputs and outputs in response to cross and bar state voltages.
Claim 37
Dependent Claim
48 words
The optical switch of claim 32, wherein the means for propagating an optical signal includes first and second optical waveguides formed by titanium diffusion in a substrate of lithium niobate, said first and second optical waveguides in parallel and closely disposed to each other in said coupling region.
Claim 38
Dependent Claim
54 words
The optical switch of claim 32, wherein the means for coupling includes at least three pairs of reverse Δβ electrodes in the coupling region for switching said first and second optical waveguides to a cross state in response to a cross state voltage and a bar state in response to a bar state voltage.
Claim 39
Dependent Claim
17 words
The optical switch of claim 32, wherein said optical switch is a three-section reverse Δβ directional coupler.
Claim 40
Dependent Claim
15 words
The optical switch of claim 35, wherein the number of coupling lengths is approximately 3.
Claim 41
Dependent Claim
191 words
An optical switching array capable of operation with uniform cross and bar state voltages at low crosstalk levels comprising a plurality of directional couplers, wherein each of said directional couplers includes: first and second optical waveguides formed in or on a substrate of electro-optic material, said first and second optical waveguides being closely disposed to each other in a coupling region having a number of coupling lengths selected from a corresponding switching diagram having cross and bar state switching curves, said switching diagram having a first axis corresponding to numbers of coupling lengths and a second axis proportional to cross and bar state voltages, said number of coupling lengths selected from a region of the switching diagram where the cross and bar state switching curves are approximately in parallel with each other and with the first axis of the switching diagram corresponding to the numbers of coupling lengths, and at least three pairs of reverse Δβ electrodes in the coupling region for switching said first and second optical waveguides to a cross state in response to a cross state voltage and a bar state in response to a bar state voltage.
Claim 42
Dependent Claim
191 words
An optical switching array capable of operation with uniform cross and bar state voltages at low crosstalk levels comprising a plurality of directional couplers, wherein each of said directional couplers includes: first and second optical waveguides formed in or on a substrate of electro-optic material, said first and second optical waveguides being closely disposed to each other in a coupling region having a number of coupling lengths selected from a corresponding switching diagram having cross and bar state switching curves, said switching diagram having a first axis corresponding to numbers of coupling lengths and a second axis proportional to cross and bar state voltages, said number of coupling lengths selected from a region of the switching diagram where the cross and bar state switching curves are approximately in parallel with each other and with the first axis of the switching diagram corresponding to the numbers of coupling lengths, and at least three pairs of reverse Δβ electrodes in the coupling region for switching said first and second optical waveguides to a cross state in response to a cross state voltage and a bar state in response to a bar state voltage.
Claim 43
Dependent Claim
145 words
An optical switching array capable of operation with uniform cross and bar state voltages at low crosstalk levels comprising a plurality of directional couplers, wherein each of said directional couplers includes: first and second optical waveguides formed in or on a substrate of electro-optic material, said first and second optical waveguides being closely disposed to each other in a coupling region having a number of coupling lengths, said number of coupling lengths selected from a region of corresponding process sensitivity plots, having cross and bar state voltage curves, where the cross and bar state voltage curves are both of approximately zero slope, and at least three pairs of reverse Δβ electrodes in the coupling region for switching said first and second optical waveguides to a cross state in response to a cross state voltage and a bar state in response to a bar state voltage.
Claim 44
Dependent Claim
145 words
An optical switching array capable of operation with uniform cross and bar state voltages at low crosstalk levels comprising a plurality of directional couplers, wherein each of said directional couplers includes: first and second optical waveguides formed in or on a substrate of electro-optic material, said first and second optical waveguides being closely disposed to each other in a coupling region having a number of coupling lengths, said number of coupling lengths selected from a region of corresponding process sensitivity plots, having cross and bar state voltage curves, where the cross and bar state voltage curves are both of approximately zero slope, and at least three pairs of reverse Δβ electrodes in the coupling region for switching said first and second optical waveguides to a cross state in response to a cross state voltage and a bar state in response to a bar state voltage.
Claim 45
Dependent Claim
163 words
An optical switching array capable of operation with uniform cross and bar state voltages at low crosstalk levels comprising a plurality of directional couplers, wherein each of said directional couplers includes: means for propagating an optical signal from one or more inputs to one or more outputs having a coupling region of a number of coupling lengths selected from a corresponding switching diagram having cross and bar state switching curves, said switching diagram having a first axis corresponding to numbers of coupling lengths and a second axis corresponding to cross and bar state voltages, said number of coupling lengths selected from a region of the switching diagram where said cross and bar state switching curves are approximately in parallel with each other and with the first axis of the switching diagram corresponding to the numbers of coupling lengths, and means for coupling said optical signal between each of said one or more inputs and outputs in response to cross and bar state voltages.
Claim 46
Dependent Claim
163 words
An optical switching array capable of operation with uniform cross and bar state voltages at low crosstalk levels comprising a plurality of directional couplers, wherein each of said directional couplers includes: means for propagating an optical signal from one or more inputs to one or more outputs having a coupling region of a number of coupling lengths selected from a corresponding switching diagram having cross and bar state switching curves, said switching diagram having a first axis corresponding to numbers of coupling lengths and a second axis corresponding to cross and bar state voltages, said number of coupling lengths selected from a region of the switching diagram where said cross and bar state switching curves are approximately in parallel with each other and with the first axis of the switching diagram corresponding to the numbers of coupling lengths, and means for coupling said optical signal between each of said one or more inputs and outputs in response to cross and bar state voltages.
Claim 47
Dependent Claim
117 words
An optical switching array capable of operation with uniform cross and bar state voltages at low crosstalk levels comprising a plurality of directional couplers, wherein each of said directional couplers includes: means for propagating an optical signal from one or more inputs to one or more outputs having a coupling region of a number of coupling lengths, said number of coupling lengths selected from a region of corresponding process sensitivity plots, having cross and bar state voltage curves, where the cross and bar state voltage curves are both of approximately zero slope, and means for coupling said optical signal between each of said one or more inputs and outputs in response to cross and bar state voltages.
Claim 48
Dependent Claim
117 words
An optical switching array capable of operation with uniform cross and bar state voltages at low crosstalk levels comprising a plurality of directional couplers, wherein each of said directional couplers includes: means for propagating an optical signal from one or more inputs to one or more outputs having a coupling region of a number of coupling lengths, said number of coupling lengths selected from a region of corresponding process sensitivity plots, having cross and bar state voltage curves, where the cross and bar state voltage curves are both of approximately zero slope, and means for coupling said optical signal between each of said one or more inputs and outputs in response to cross and bar state voltages.
Claim 49
Independent Claim
158 words
A system for switching optical signals capable of operation with uniform cross and bar state voltages at low crosstalk levels comprising a plurality of optical switching arrays, each of said arrays having a plurality of directional couplers, wherein each of said directional couplers includes: first and second optical waveguides formed in or on a substrate of electro-optic material, said first and second optical waveguides being closely disposed to each other in a coupling region having a number of coupling lengths, said number of coupling lengths selected from a region of corresponding process sensitivity plots, having cross and bar state voltage curves, where the cross and bar state voltage curves are both of approximately zero slope, and at least three pairs of reverse Δβ electrodes in the coupling region for switching said first and second optical waveguides to a cross state in response to a cross state voltage and a bar state in response to a bar state voltage.
Claim 50
Independent Claim
158 words
A system for switching optical signals capable of operation with uniform cross and bar state voltages at low crosstalk levels comprising a plurality of optical switching arrays, each of said arrays having a plurality of directional couplers, wherein each of said directional couplers includes: first and second optical waveguides formed in or on a substrate of electro-optic material, said first and second optical waveguides being closely disposed to each other in a coupling region having a number of coupling lengths, said number of coupling lengths selected from a region of corresponding process sensitivity plots, having cross and bar state voltage curves, where the cross and bar state voltage curves are both of approximately zero slope, and at least three pairs of reverse Δβ electrodes in the coupling region for switching said first and second optical waveguides to a cross state in response to a cross state voltage and a bar state in response to a bar state voltage.
Claim 51
Independent Claim
176 words
A system for switching optical signals capable of operation with uniform cross and bar state voltages at low crosstalk levels comprising a plurality of optical switching arrays, each of said arrays having a plurality of directional couplers, wherein each of said directional couplers includes: means for propagating an optical signal from one or more inputs to one or more outputs having a coupling region of a number of coupling lengths selected from a corresponding switching diagram having cross and bar state switching curves, said switching diagram having a first axis corresponding to numbers of coupling lengths and a second axis proportional to cross and bar state voltages, said number of coupling lengths selected from a region of the switching diagram where said cross and bar state switching curves are approximately in parallel with each other and with the first axis of the switching diagram corresponding to the numbers of coupling lengths, and means for coupling said optical signal between each of said one or more inputs and outputs in response to cross and bar state voltages.
Claim 52
Independent Claim
176 words
A system for switching optical signals capable of operation with uniform cross and bar state voltages at low crosstalk levels comprising a plurality of optical switching arrays, each of said arrays having a plurality of directional couplers, wherein each of said directional couplers includes: means for propagating an optical signal from one or more inputs to one or more outputs having a coupling region of a number of coupling lengths selected from a corresponding switching diagram having cross and bar state switching curves, said switching diagram having a first axis corresponding to numbers of coupling lengths and a second axis proportional to cross and bar state voltages, said number of coupling lengths selected from a region of the switching diagram where said cross and bar state switching curves are approximately in parallel with each other and with the first axis of the switching diagram corresponding to the numbers of coupling lengths, and means for coupling said optical signal between each of said one or more inputs and outputs in response to cross and bar state voltages.
Claim 53
Independent Claim
130 words
A system for switching optical signals capable of operation with uniform cross and bar state voltages at low crosstalk levels comprising a plurality of optical switching arrays, each of said arrays having a plurality of directional couplers, wherein each of said directional couplers includes: means for propagating an optical signal from one or more inputs to one or more outputs having a coupling region of a number of coupling lengths, said number of coupling lengths selected from a region of corresponding process sensitivity plots, having cross and bar state voltage curves, where the cross and bar state voltage curves are both of approximately zero slope, and means for coupling said optical signal between each of said one or more inputs and outputs in response to cross and bar state voltages.
Claim 54
Independent Claim
130 words
A system for switching optical signals capable of operation with uniform cross and bar state voltages at low crosstalk levels comprising a plurality of optical switching arrays, each of said arrays having a plurality of directional couplers, wherein each of said directional couplers includes: means for propagating an optical signal from one or more inputs to one or more outputs having a coupling region of a number of coupling lengths, said number of coupling lengths selected from a region of corresponding process sensitivity plots, having cross and bar state voltage curves, where the cross and bar state voltage curves are both of approximately zero slope, and means for coupling said optical signal between each of said one or more inputs and outputs in response to cross and bar state voltages.
Claim 55
Independent Claim
204 words
A system for switching optical signals capable of operation with uniform cross and bar state voltages at low crosstalk levels comprising a plurality of optical switching arrays, each of said arrays having a plurality of directional couplers, wherein each of said directional couplers includes: first and second optical waveguides formed in or on a substrate of electro-optic material, said first and second optical waveguides being closely disposed to each other in a coupling region having a number of coupling lengths selected from a corresponding switching diagram having cross and bar state switching curves, said switching diagram having a first axis corresponding to numbers of coupling lengths and a second axis proportional to cross and bar state voltages, said number of coupling lengths selected from a region of the switching diagram where the cross and bar state switching curves are approximately in parallel with each other and with the first axis of the switching diagram corresponding to the numbers of coupling lengths, and at least three pairs of reverse Δβ electrodes in the coupling region for switching said first and second optical waveguides to a cross state in response to a cross state voltage and a bar state in response to a bar state voltage.
Claim 56
Independent Claim
204 words
A system for switching optical signals capable of operation with uniform cross and bar state voltages at low crosstalk levels comprising a plurality of optical switching arrays, each of said arrays having a plurality of directional couplers, wherein each of said directional couplers includes: first and second optical waveguides formed in or on a substrate of electro-optic material, said first and second optical waveguides being closely disposed to each other in a coupling region having a number of coupling lengths selected from a corresponding switching diagram having cross and bar state switching curves, said switching diagram having a first axis corresponding to numbers of coupling lengths and a second axis proportional to cross and bar state voltages, said number of coupling lengths selected from a region of the switching diagram where the cross and bar state switching curves are approximately in parallel with each other and with the first axis of the switching diagram corresponding to the numbers of coupling lengths, and at least three pairs of reverse Δβ electrodes in the coupling region for switching said first and second optical waveguides to a cross state in response to a cross state voltage and a bar state in response to a bar state voltage.
Claim 57
Independent Claim
258 words
A method of fabricating an optical switching array of directional couplers capable of operation with uniform cross and bar state voltages at low crosstalk levels comprising the steps of: fabricating first and second waveguide patterns for each of the directional couplers in the array on a substrate of electro-optic material using suitable thin film deposition techniques and photolithography, diffusing a metal dopant into the substrate of electro-optic material for each of said first and second waveguide patterns to form first and second waveguides for each of the directional couplers in the array, said first and second waveguides being closely disposed to each other in a coupling region having a number of coupling lengths selected from a switching diagram having cross and bar state switching curves, said switching diagram having a first axis corresponding to numbers of coupling lengths and a second axis proportional to cross and bar state voltages, said number of coupling lengths selected from a region of the switching diagram where the cross and bar state switching curves are approximately in parallel with each other and with the first axis of the switching diagram corresponding to the numbers of coupling lengths, and fabricating three or more sections of reverse Δβ electrodes on the substrate using suitable thin film deposition techniques and photolithography, said electrodes positioned in the coupling region of each of the couplers in the array for switching said first and second waveguides to a cross state in response to a cross state voltage and a bar state in response to a bar state voltage.
Claim 58
Independent Claim
258 words
A method of fabricating an optical switching array of directional couplers capable of operation with uniform cross and bar state voltages at low crosstalk levels comprising the steps of: fabricating first and second waveguide patterns for each of the directional couplers in the array on a substrate of electro-optic material using suitable thin film deposition techniques and photolithography, diffusing a metal dopant into the substrate of electro-optic material for each of said first and second waveguide patterns to form first and second waveguides for each of the directional couplers in the array, said first and second waveguides being closely disposed to each other in a coupling region having a number of coupling lengths selected from a switching diagram having cross and bar state switching curves, said switching diagram having a first axis corresponding to numbers of coupling lengths and a second axis proportional to cross and bar state voltages, said number of coupling lengths selected from a region of the switching diagram where the cross and bar state switching curves are approximately in parallel with each other and with the first axis of the switching diagram corresponding to the numbers of coupling lengths, and fabricating three or more sections of reverse Δβ electrodes on the substrate using suitable thin film deposition techniques and photolithography, said electrodes positioned in the coupling region of each of the couplers in the array for switching said first and second waveguides to a cross state in response to a cross state voltage and a bar state in response to a bar state voltage.
Claim 59
Dependent Claim
88 words
The method of claim 45, wherein the step of fabricating the waveguide patterns on the substrate includes the steps of: depositing a layer of photosensitive material on said substrate, placing a waveguide mask over the photosensitive layer, said mask defining said first and second waveguide patterns for each of the directional couplers in the array, exposing the photosensitive layer on said substrate to ultraviolet light through the mask, and developing the photosensitive layer to form openings in the photosensitive layer corresponding to said first and second waveguide patterns.
Claim 60
Dependent Claim
88 words
The method of claim 46, wherein the step of diffusing the metal dopant into the substrate includes the steps of: depositing a thin layer of metal dopant on the photosensitive layer and in the openings, applying a solvent to remove the metal dopant on the photosensitive layer and thereby leaving patterns of the metal dopant in the openings corresponding to said first and second waveguide patterns, and diffusing said waveguide patterns into the substrate to form said first and second waveguides for each directional coupler in the array.
Claim 61
Dependent Claim
11 words
The method of claim 47, wherein the metal dopant is titanium.
Claim 62
Dependent Claim
24 words
The method of claim 45, wherein the method further includes the step of depositing a dielectric layer on the substrate before fabricating the electrodes.
Claim 63
Dependent Claim
13 words
The method of claim 49, wherein the dielectric layer is SiO 2 .
Claim 64
Independent Claim
213 words
A method of fabricating an optical switching array of directional couplers capable of operation with uniform cross and bar state voltages at low crosstalk levels comprising the steps of: fabricating first and second waveguide patterns for each of the directional couplers in the array on a substrate of electro-optic material using suitable thin film deposition techniques and photolithography, diffusing a metal dopant into the substrate of electro-optic material for each of said first and second waveguide patterns to form first and second waveguides for each of the directional couplers in the array, said first and second waveguides being closely disposed to each other in a coupling region having a number of coupling lengths, said number of coupling lengths selected from a region of corresponding process sensitivity plots, having cross and bar state voltage curves, where the cross and bar state voltage curves are both of approximately zero slope, and fabricating three or more sections of reverse Δβ electrodes on the substrate using suitable thin film deposition techniques and photolithography, said electrodes positioned in the coupling region of each of the couplers in the array for switching said first and second waveguides to a cross state in response to a cross state voltage and a bar state in response to a bar state voltage.
Claim 65
Independent Claim
213 words
A method of fabricating an optical switching array of directional couplers capable of operation with uniform cross and bar state voltages at low crosstalk levels comprising the steps of: fabricating first and second waveguide patterns for each of the directional couplers in the array on a substrate of electro-optic material using suitable thin film deposition techniques and photolithography, diffusing a metal dopant into the substrate of electro-optic material for each of said first and second waveguide patterns to form first and second waveguides for each of the directional couplers in the array, said first and second waveguides being closely disposed to each other in a coupling region having a number of coupling lengths, said number of coupling lengths selected from a region of corresponding process sensitivity plots, having cross and bar state voltage curves, where the cross and bar state voltage curves are both of approximately zero slope, and fabricating three or more sections of reverse Δβ electrodes on the substrate using suitable thin film deposition techniques and photolithography, said electrodes positioned in the coupling region of each of the couplers in the array for switching said first and second waveguides to a cross state in response to a cross state voltage and a bar state in response to a bar state voltage.
Claim 66
Dependent Claim
88 words
The method of claim 51, wherein the step of fabricating the waveguide patterns on the substrate includes the steps of: depositing a layer of photosensitive material on said substrate, placing a waveguide mask over the photosensitive layer, said mask defining said first and second waveguide patterns for each of the directional couplers in the array, exposing the photosensitive layer on said substrate to ultraviolet light through the mask, and developing the photosensitive layer to form openings in the photosensitive layer corresponding to said first and second waveguide patterns.
Claim 67
Dependent Claim
88 words
The method of claim 52, wherein the step of diffusing the metal dopant into the substrate includes the steps of: depositing a thin layer of metal dopant on the photosensitive layer and in the openings, applying a solvent to remove the metal dopant on the photosensitive layer and thereby leaving patterns of the metal dopant in the openings corresponding to said first and second waveguide patterns, and diffusing said waveguide patterns into the substrate to form said first and second waveguides for each directional coupler in the array.
Claim 68
Dependent Claim
11 words
The method of claim 53, wherein the metal dopant is titanium.
Claim 69
Dependent Claim
24 words
The method of claim 51, wherein the method further includes the step of depositing a dielectric layer on the substrate before fabricating the electrodes.
Claim 70
Dependent Claim
13 words
The method of claim 55, wherein the dielectric layer is SiO 2 .
Claim 71
Independent Claim
251 words
A method of fabricating an optical switching array of directional couplers capable of operation with uniform cross and bar state voltages at low crosstalk levels comprising the steps of: fabricating first and second waveguide patterns for each of the directional couplers in the array on a substrate of electro-optic material using suitable thin film deposition techniques and photolithography, forming first and second waveguides for each of the directional couplers in the array by an ion-exchange process for each of said first and second waveguide patterns, said first and second waveguides being closely disposed to each other in a coupling region having a number of coupling lengths selected from a switching diagram having cross and bar state switching curves, said switching diagram having a first axis corresponding to numbers of coupling lengths and a second axis proportional to cross and bar state voltages, said number of coupling lengths selected from a region of the switching diagram where the cross and bar state switching curves are approximately in parallel with each other and with the first axis of the switching diagram corresponding to the numbers of coupling lengths, and fabricating three or more sections of reverse Δβ electrodes on said substrate using suitable thin film deposition techniques and photolithography, said electrodes positioned in the coupling region of each of the couplers in the array for switching said cross and second waveguides to a cross state in response to a cross state voltage and a bar state in response to a bar state voltage.
Claim 72
Independent Claim
251 words
A method of fabricating an optical switching array of directional couplers capable of operation with uniform cross and bar state voltages at low crosstalk levels comprising the steps of: fabricating first and second waveguide patterns for each of the directional couplers in the array on a substrate of electro-optic material using suitable thin film deposition techniques and photolithography, forming first and second waveguides for each of the directional couplers in the array by an ion-exchange process for each of said first and second waveguide patterns, said first and second waveguides being closely disposed to each other in a coupling region having a number of coupling lengths selected from a switching diagram having cross and bar state switching curves, said switching diagram having a first axis corresponding to numbers of coupling lengths and a second axis proportional to cross and bar state voltages, said number of coupling lengths selected from a region of the switching diagram where the cross and bar state switching curves are approximately in parallel with each other and with the first axis of the switching diagram corresponding to the numbers of coupling lengths, and fabricating three or more sections of reverse Δβ electrodes on said substrate using suitable thin film deposition techniques and photolithography, said electrodes positioned in the coupling region of each of the couplers in the array for switching said cross and second waveguides to a cross state in response to a cross state voltage and a bar state in response to a bar state voltage.
Claim 73
Dependent Claim
90 words
The method of claim 57, wherein the step of fabricating the waveguide patterns on the substrate includes the steps of: depositing a layer of photosensitive material on said substrate, placing a waveguide mask over the photosensitive layer, said mask defining said first and second waveguide patterns for each of the directional couplers in the array, exposing the photosensitive layer on said substrate to ultraviolet light through the mask, and developing the photosensitive layer to form said first and second waveguide patterns for each of the directional couplers in the array.
Claim 74
Dependent Claim
74 words
The method of claim 58, wherein the step of forming said first and second waveguides by an ion-exchange process includes the steps of: depositing a metal layer on the substrate and on the photosensitive layer corresponding to said first and second waveguide patterns; removing the photosensitive layer corresponding to said first and second waveguide patterns and the metal layer thereon; and placing the substrate in benzoic acid, at 250° C., for a few hours.
Claim 75
Dependent Claim
11 words
The method of claim 59, wherein the metal layer is Au.
Claim 76
Independent Claim
206 words
A method of fabricating an optical switching array of directional couplers capable of operation with uniform cross and bar state voltages at low crosstalk levels comprising the steps of: fabricating first and second waveguide patterns for each of the directional couplers in the array on a substrate of electro-optic material using suitable thin film deposition techniques and photolithography, forming first and second waveguides for each of the directional couplers in the array by an ion-exchange process for each of said first and second waveguide patterns, said first and second waveguides being closely disposed to each other in a coupling region having a number of coupling lengths, said number of coupling lengths selected from a region of corresponding process sensitivity plots, having cross and bar state voltage curves, where the cross and bar state voltage curves are both of approximately zero slope, and fabricating three or more sections of reverse Δβ electrodes on said substrate using suitable thin film deposition techniques and photolithography, said electrodes positioned in the coupling region of each of the couplers in the array for switching said cross and second waveguides to a cross state in response to a cross state voltage and a bar state in response to a bar state voltage.
Claim 77
Independent Claim
206 words
A method of fabricating an optical switching array of directional couplers capable of operation with uniform cross and bar state voltages at low crosstalk levels comprising the steps of: fabricating first and second waveguide patterns for each of the directional couplers in the array on a substrate of electro-optic material using suitable thin film deposition techniques and photolithography, forming first and second waveguides for each of the directional couplers in the array by an ion-exchange process for each of said first and second waveguide patterns, said first and second waveguides being closely disposed to each other in a coupling region having a number of coupling lengths, said number of coupling lengths selected from a region of corresponding process sensitivity plots, having cross and bar state voltage curves, where the cross and bar state voltage curves are both of approximately zero slope, and fabricating three or more sections of reverse Δβ electrodes on said substrate using suitable thin film deposition techniques and photolithography, said electrodes positioned in the coupling region of each of the couplers in the array for switching said cross and second waveguides to a cross state in response to a cross state voltage and a bar state in response to a bar state voltage.
Claim 78
Dependent Claim
90 words
The method of claim 61, wherein the step of fabricating the waveguide patterns on the substrate includes the steps of: depositing a layer of photosensitive material on said substrate, placing a waveguide mask over the photosensitive layer, said mask defining said first and second waveguide patterns for each of the directional couplers in the array, exposing the photosensitive layer on said substrate to ultraviolet light through the mask, and developing the photosensitive layer to form said first and second waveguide patterns for each of the directional couplers in the array.
Claim 79
Dependent Claim
74 words
The method of claim 62, wherein the step of forming said first and second waveguides by an ion-exchange process includes the steps of: depositing a metal layer on the substrate and on the photosensitive layer corresponding to said first and second waveguide patterns; removing the photosensitive layer corresponding to said first and second waveguide patterns and the metal layer thereon; and placing the substrate in benzoic acid, at 250° C., for a few hours.
Claim 80
Dependent Claim
11 words
The method of claim 63, wherein the metal layer is Au.
Claim 81
Independent Claim
223 words
A method of fabricating an optical switching array of directional couplers capable of operation with uniform cross and bar state voltages at low crosstalk levels comprising the steps of: fabricating first and second waveguides for each of the directional couplers in the array on a substrate of electro-optic material using suitable thin film deposition techniques and photolithography, said first and second waveguides being closely disposed to each other in a coupling region having a number of coupling lengths selected from a switching diagram having cross and bar state switching curves, said switching diagram having a first axis corresponding to numbers of coupling lengths and a second axis proportional to cross and bar state voltages, said number of coupling lengths selected from a region of the switching diagram where the cross and bar state switching curves are approximately in parallel with each other and with the first axis of the switching diagram corresponding to the numbers of coupling lengths, and fabricating three or more sections of reverse Δβ electrodes on the substrate using suitable thin film deposition techniques and photolithography, said electrodes positioned in the coupling region of each of the couplers in the array for switching said first and second waveguides to a cross state in response to a cross state voltage and a bar state in response to a bar state voltage.
Claim 82
Independent Claim
223 words
A method of fabricating an optical switching array of directional couplers capable of operation with uniform cross and bar state voltages at low crosstalk levels comprising the steps of: fabricating first and second waveguides for each of the directional couplers in the array on a substrate of electro-optic material using suitable thin film deposition techniques and photolithography, said first and second waveguides being closely disposed to each other in a coupling region having a number of coupling lengths selected from a switching diagram having cross and bar state switching curves, said switching diagram having a first axis corresponding to numbers of coupling lengths and a second axis proportional to cross and bar state voltages, said number of coupling lengths selected from a region of the switching diagram where the cross and bar state switching curves are approximately in parallel with each other and with the first axis of the switching diagram corresponding to the numbers of coupling lengths, and fabricating three or more sections of reverse Δβ electrodes on the substrate using suitable thin film deposition techniques and photolithography, said electrodes positioned in the coupling region of each of the couplers in the array for switching said first and second waveguides to a cross state in response to a cross state voltage and a bar state in response to a bar state voltage.
Claim 83
Dependent Claim
83 words
The method of claim 65, wherein the step of fabricating the first and second waveguides on the substrate includes the steps of: depositing one or more layers of semiconductor material on said substrate, placing a waveguide mask over the semiconductor layers, said mask defining said first and second waveguides for each of the directional couples in the array, exposing said semiconductor layers on said substrate to ultraviolet light through the mask, and developing the semiconductor layers to form said first and second waveguides.
Claim 84
Dependent Claim
12 words
The method of claim 65, wherein the semiconductor layers comprise InGaAsP/InP heterostructures.
Claim 85
Independent Claim
178 words
A method of fabricating an optical switching array of directional couplers capable of operation with uniform cross and bar state voltages at low crosstalk levels comprising the steps of: fabricating first and second waveguides for each of the directional couplers in the array on a substrate of electro-optic material using suitable thin film deposition techniques and photolithography, said first and second waveguides being closely disposed to each other in a coupling region having a number of coupling lengths, said number of coupling lengths selected from a region of corresponding process sensitivity plots, having cross and bar state voltage curves, where the cross and bar state voltage curves are both of approximately zero slope, and fabricating three or more sections of reverse Δβ electrodes on the substrate using suitable thin film deposition techniques and photolithography, said electrodes positioned in the coupling region of each of the couplers in the array for switching said first and second waveguides to a cross state in response to a cross state voltage and a bar state in response to a bar state voltage.
Claim 86
Independent Claim
178 words
A method of fabricating an optical switching array of directional couplers capable of operation with uniform cross and bar state voltages at low crosstalk levels comprising the steps of: fabricating first and second waveguides for each of the directional couplers in the array on a substrate of electro-optic material using suitable thin film deposition techniques and photolithography, said first and second waveguides being closely disposed to each other in a coupling region having a number of coupling lengths, said number of coupling lengths selected from a region of corresponding process sensitivity plots, having cross and bar state voltage curves, where the cross and bar state voltage curves are both of approximately zero slope, and fabricating three or more sections of reverse Δβ electrodes on the substrate using suitable thin film deposition techniques and photolithography, said electrodes positioned in the coupling region of each of the couplers in the array for switching said first and second waveguides to a cross state in response to a cross state voltage and a bar state in response to a bar state voltage.
Claim 87
Dependent Claim
83 words
The method of claim 68, wherein the step of fabricating the first and second waveguides on the substrate includes the steps of: depositing one or more layers of semiconductor material on said substrate, placing a waveguide mask over the semiconductor layers, said mask defining said first and second waveguides for each of the directional couples in the array, exposing said semiconductor layers on said substrate to ultraviolet light through the mask, and developing the semiconductor layers to form said first and second waveguides.
Claim 88
Dependent Claim
12 words
The method of claim 68, wherein the semiconductor layers comprise InGaAsP/InP heterostructures.
References Cited (Backward Citations)
US4211467A
Cited
US4679893A
Cited
US4763974A
Cited
US4871223A
Cited
US5103491A
Cited
US5066086A
Cited
US5004447A
Cited
US5111517A
Cited
US5146518A
Cited
USPTO Annuity & Maintenance Windows
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