Patent US4990818A successfully refreshed from Google Patents.
US4990818A
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Method of making a transducer from a boule of lithium tetraborate and transducer so made
Assignee: United States Department of the Army
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Filing: 1989-10-23
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Granted: 1991-02-05
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Expires: 2009-10-23
Abstract
Abstract An improved transducer is obtained by providing a plate of lithium tetrabte with a doubly rotated orientation of φ≅17° to 21° and θ≅54° to 58° where doubly rotated orientations are described by the IEEE notation widely known in the art as (YXwl)φ/θ.
Inventors
- 👤 Arthur Ballato
- 👤 John A. Kosinski
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 12:11
CPC Classifications
H; H10; H10N; H10N30/00; H10N30/80; H10N30/85; H10N30/853; H10N30/8542
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
68 words
In a transducer including a lapped and polished plate of lithium tetraborate with metallic electrodes deposited on the major surfaces of the plate and the plate mounted in an evacuated sealed enclosure, the improvement of providing the plate with a doubly rotated orientation of φ≅17° to 21° and θ≅54° to 58° where doubly rotated orientations are described by the IEEE notation widely known in the art as (YXwl)φ/θ.
Claim 2
Dependent Claim
68 words
In a transducer including a lapped and polished plate of lithium tetraborate with metallic electrodes deposited on the major surfaces of the plate and the plate mounted in an evacuated sealed enclosure, the improvement of providing the plate with a doubly rotated orientation of φ≅17° to 21° and θ≅54° to 58° where doubly rotated orientations are described by the IEEE notation widely known in the art as (YXwl)φ/θ.
Claim 3
Dependent Claim
22 words
In a transducer according to claim 1, the improvement of providing the plate with a doubly rotated orientation of φ≅19° and θ≅56°.
References Cited (Backward Citations)
US4523119A
Cited
US4634913A
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US4634913B1
Cited
US4672255A
Cited
US4772817A
Cited
US4950937A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-02-04 | 1994-08-06 | 1995-02-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-02-04 | 1998-08-06 | 1999-02-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-02-04 | 2002-08-06 | 2003-02-05 | $7700.00 | Window Closed / Lapsed |