Patent US4381138A successfully refreshed from Google Patents.
US4381138A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrooptic devices
Assignee: AT&T Inc
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Filing: 1980-08-25
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Granted: 1983-04-26
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Expires: 2000-08-25
Abstract
Abstract The response, as a function of frequency, of electrooptic mode converters using comb electrodes has been found to include several peaks at frequencies above and below the desired frequency. These spurious peaks appear to be caused by fringing of the electric field which effectively changes the spatial period of the electrode fingers. To prevent this unwanted coupling, channels have been etched between the comb fingers. The result is to confine the electric field to the narrow region between opposing electrode fingers, thereby minimizing the spurious responses. It also serves to reduce the magnitude of the applied voltage required to produce the same field strength.
Inventors
- 👤 Lawrence L. Buhl
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 03:58
CPC Classifications
G; G02; G02F; G02F1/00; G02F1/01; G02F1/03; G02F1/035; G02F1/0353; G02F1/29; G02F1/31; G02F1/313; G02F1/3132; G02F1/0136; G02F1/0142; G02F2201/00; G02F2201/06; G02F2201/066; G02F2201/12; G02F2201/124; G02F2203/00; G02F2203/05; G02F2203/055
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
129 words
An electrooptic device (30, 60) at least one optical waveguiding region (11, 50) embedded in a substrate (12, 52) of electrooptic material of lower refractive index; means for providing periodic regions of electric field within said substrate longitudinally distributed along the length of said waveguiding region including: a pair of comb electrodes (13-14, 53-54) having fingers (13-1, 13-2 . . . 14-1, 14-2 . . . , 53-1, 53-2 . . . 54-1, 54-2) whose ends are disposed opposite each other along said length; CHARACTERIZED IN THAT portions (1, 2, 3) of the substrate between adjacent fingers are removed so as to minimize fringing of the electric field between pairs of opposing fingers (13-1, 14-1; 13-2, 14-2 . . . ; 53-1, 54-1; 53-2, 54-2 . . . ).
Claim 2
Dependent Claim
129 words
An electrooptic device (30, 60) at least one optical waveguiding region (11, 50) embedded in a substrate (12, 52) of electrooptic material of lower refractive index; means for providing periodic regions of electric field within said substrate longitudinally distributed along the length of said waveguiding region including: a pair of comb electrodes (13-14, 53-54) having fingers (13-1, 13-2 . . . 14-1, 14-2 . . . , 53-1, 53-2 . . . 54-1, 54-2) whose ends are disposed opposite each other along said length; CHARACTERIZED IN THAT portions (1, 2, 3) of the substrate between adjacent fingers are removed so as to minimize fringing of the electric field between pairs of opposing fingers (13-1, 14-1; 13-2, 14-2 . . . ; 53-1, 54-1; 53-2, 54-2 . . . ).
Claim 3
Dependent Claim
27 words
The device according to claim 1 comprising a single waveguiding region (11) wherein said electrodes (13, 14) are aligned along opposite sides of said waveguiding region (11).
Claim 4
Dependent Claim
37 words
The device according to claim 2 wherein the portions (1, 2) of said substrate bounded by said fingers (13-1, 13-2 . . . , 14-1, 14-2 . . . ) and said waveguiding region (11) are removed.
Claim 5
Dependent Claim
37 words
The device according to claim 1 comprising a pair of coupled waveguiding regions (50, 51) wherein said electrodes (53, 54) are superimposed over said waveguiding regions and extend at least up to the region of substrate therebetween.
Claim 6
Dependent Claim
35 words
The device according to claim 4 wherein the portions (3) of substrate bounded by said fingers (53-1, 53-2 . . . 54-1, 54-2 . . . ) and said waveguiding regions (50, 51) are removed.
Claim 7
Dependent Claim
20 words
The device according to claim 1 wherein said portions of substrate are removed to a depth of approximately one micron.
References Cited (Backward Citations)
US3877782A
Cited
US4236785A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-04-25 | 1986-10-25 | 1987-04-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-04-25 | 1990-10-25 | 1991-04-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-04-25 | 1994-10-25 | 1995-04-26 | $7700.00 | Window Closed / Lapsed |