Patent US4707631A successfully refreshed from Google Patents.
US4707631A
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Isotropic acoustic wave substrate
Assignee: Northrop Grumman Corp
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Filing: 1986-07-17
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Granted: 1987-11-17
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Expires: 2006-07-17
Abstract
Abstract A surface acoustic wave (SAW) diffraction-effect or interference-effect device with a highly isotropic substrate having a high coupling coefficient and low attenuation losses. The use of X-propagating rotated-Y-cut lithium niobate as the SAW substrate, with the Y rotation angle selected at 121 degrees, provides a practically isotropic material, with a high coupling coefficient and relatively low attenuation losses.
Inventors
- 👤 Robert B. Stokes
- 👤 Kuo-Hsiung Yen
- 👤 Kei-Fung Lau
- 👤 Reynold S. Kagiwada
- 👤 Michael J. Delaney
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 07:29
CPC Classifications
H; H03; H03H; H03H9/00; H03H9/02; H03H9/125; H03H9/145; H03H9/14544; H03H9/1455; H03H3/00; H03H3/007; H03H3/08; H03H9/02535; H03H9/02543; H03H9/02559
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
74 words
For use in a two-dimensional diffraction-effect or interference-effect surface acoustic wave (SAW) device, a structure comprising: a substantially isotropic SAW substrate of X-propagating rotated Y-cut lithium niobate (LiNbO 3 ) having a Y rotation angle of approximately 121 degrees; and a plurality of electro-acoustic transducers disposed on a surface of said substrate at substantially different angles relative to the principal X propagating direction, thereby directly exploiting the diffraction or interference properties of acoustic waves.
Claim 2
Dependent Claim
74 words
For use in a two-dimensional diffraction-effect or interference-effect surface acoustic wave (SAW) device, a structure comprising: a substantially isotropic SAW substrate of X-propagating rotated Y-cut lithium niobate (LiNbO 3 ) having a Y rotation angle of approximately 121 degrees; and a plurality of electro-acoustic transducers disposed on a surface of said substrate at substantially different angles relative to the principal X propagating direction, thereby directly exploiting the diffraction or interference properties of acoustic waves.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1990-11-16 | 1991-05-18 | 1991-11-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-11-16 | 1995-05-18 | 1995-11-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-11-16 | 1999-05-18 | 1999-11-17 | $7700.00 | Window Closed / Lapsed |