Patent US3801185A successfully refreshed from Google Patents.
US3801185A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Switch for thin-film optics
Assignee: AT&T Inc
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Filing: 1972-12-06
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Granted: 1974-04-02
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Expires: 1992-12-06
Abstract
Abstract An optical switch for thin-film light guides utilizes electrically induced changes in the index of refraction of the switch material to produce the switching effect. Electrodes located along the length of the switch material and separated from it by an insulating layer induce an electric field in a region of the switch material when a voltage difference is applied to them. This causes the index of refraction to increase in that region to such an extent that a light guide is formed in the switch material, allowing transmission through the switch. Removal of the voltage destroys the guide, thereby stopping transmission.
Inventors
- 👤 V Ramaswamy
- 👤 R Standley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 02:53
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/03; G02F1/035
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
89 words
An electro-optic switch comprising: a substrate of electro-optic material having a raised ridge extending longitudinally along one surface; a dielectric material covering said ridge, the index of refraction of said dielectric material being less than the index of refraction of said substrate; and means for raising the index of refraction of said ridge above that of the rest of said substrate in a substantially uniform manner, comprising first and second ridge electrodes located along opposite sides of said ridge, respectively, and means for applying a voltage between said electrodes.
Claim 2
Dependent Claim
89 words
An electro-optic switch comprising: a substrate of electro-optic material having a raised ridge extending longitudinally along one surface; a dielectric material covering said ridge, the index of refraction of said dielectric material being less than the index of refraction of said substrate; and means for raising the index of refraction of said ridge above that of the rest of said substrate in a substantially uniform manner, comprising first and second ridge electrodes located along opposite sides of said ridge, respectively, and means for applying a voltage between said electrodes.
Claim 3
Dependent Claim
100 words
An electro-optic switch comprising: a substrate of electro-optic material having an elongated raised ridge disposed on one surface thereof; a layer of dielectric material overlying said surface including said ridge, the index of refractiOn of said dielectric material being less than the index of refraction of said substrate; and means for raising the index of refraction of said ridge above that of the rest of said substrate in a substantially uniform manner, comprising first and second electrodes imbedded in said layer of dielectric material along opposite sides of said ridge, respectively, and means for applying a voltage between said electrodes.
Claim 4
Dependent Claim
100 words
An electro-optic switch comprising: a substrate of electro-optic material having an elongated raised ridge disposed on one surface thereof; a layer of dielectric material overlying said surface including said ridge, the index of refractiOn of said dielectric material being less than the index of refraction of said substrate; and means for raising the index of refraction of said ridge above that of the rest of said substrate in a substantially uniform manner, comprising first and second electrodes imbedded in said layer of dielectric material along opposite sides of said ridge, respectively, and means for applying a voltage between said electrodes.
Claim 5
Dependent Claim
17 words
An electro-optic switch as claimed in claim 2 wherein said dielectric material consists of poly(methyl methacrylate) (PMMA).
Claim 6
Dependent Claim
39 words
An electro-optic switch as claimed in claim 2 wherein the electro-optic material of said substrate is selected from the group of materials consisting of potassium dihydrogen phosphate (KDP), lithium niobate (LiNbO3), lithium tantalate (LiTaO3), and ammonium dihydrogen phosphate (ADP).
References Cited (Backward Citations)
US3464762A
Cited
US3736046A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-04-01 | 1977-10-01 | 1978-04-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-04-01 | 1981-10-01 | 1982-04-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-04-01 | 1985-10-01 | 1986-04-02 | $7700.00 | Window Closed / Lapsed |