US4055821A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Acoustic ridge transversal filter
Assignee: Texas Instruments Inc
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Filing: 1976-05-11
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Granted: 1977-10-25
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Expires: 1996-05-11
Abstract
Abstract An improved acoustic waveguide structure which comprises a ridge waveguide disposed in a horizontal direction extending outwardly from a substrate. The horizontal orientation of the waveguide which is in the form of a ledge results in particle motion of the ledge predominantly normal to the substrate plane with the largest motion at the free edge of the ledge and almost no motion in the substrate, thereby permitting a plurality of such structures to be densely packed on a common substrate.
Inventors
- 👤 Robert S. Wagers
- 👤 Clinton S. Hartmann
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 21:37
CPC Classifications
G; G10; G10K; G10K11/00; G10K11/18; G10K11/24; G01; G01N; G01N2291/00; G01N2291/02; G01N2291/024; G01N2291/02491; G01N2291/04; G01N2291/042; G01N2291/0427
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
86 words
A transversal filter comprising: a substrate; a horizontal ledge having at least a top surface portion thereof made of piezoelectric material, said ledge extending outwardly from said substrate with the top surface portion of said ledge being coplanar with the top surface of said substrate, said substrate and said ledge defining an acoustic waveguide; and at least one tapped transducer deposited on said ledge comprising a transducer pad having a plurality of electrode fingers extending therefrom in a lateral direction toward the edge of said ledge.
Claim 2
Dependent Claim
86 words
A transversal filter comprising: a substrate; a horizontal ledge having at least a top surface portion thereof made of piezoelectric material, said ledge extending outwardly from said substrate with the top surface portion of said ledge being coplanar with the top surface of said substrate, said substrate and said ledge defining an acoustic waveguide; and at least one tapped transducer deposited on said ledge comprising a transducer pad having a plurality of electrode fingers extending therefrom in a lateral direction toward the edge of said ledge.
Claim 3
Dependent Claim
45 words
A transversal filter as set forth in claim 1, wherein said horizontal ledge is of composite form and includes a body portion of a single crystal material, and a layer of piezoelectric material deposited on said body portion to define said top surface portion thereof.
Claim 4
Dependent Claim
17 words
A transversal filter as set forth in claim 1, wherein said horizontal ledge has a wedge-shaped geometry.
Claim 5
Dependent Claim
89 words
A transversal filter comprising: a substrate; a horizontal ledge having a least a top surface portion thereof made of piezoelectric material, said ledge extending outwardly from said substrate with the top surface portion of said ledge being coplanar with the top surface of said substrate, said substrate and said ledge defining an acoustic waveguide; and an input transducer deposited on one end of said ledge and an output transducer deposited on the other end of said ledge, with at least one of said input and output transducers being tapped.
Claim 6
Dependent Claim
89 words
A transversal filter comprising: a substrate; a horizontal ledge having a least a top surface portion thereof made of piezoelectric material, said ledge extending outwardly from said substrate with the top surface portion of said ledge being coplanar with the top surface of said substrate, said substrate and said ledge defining an acoustic waveguide; and an input transducer deposited on one end of said ledge and an output transducer deposited on the other end of said ledge, with at least one of said input and output transducers being tapped.
Claim 7
Dependent Claim
45 words
A transversal filter as set forth in claim 4, wherein said horizontal ledge is of composite form and includes a body portion of a single crystal material, and a layer of piezoelectric material deposited on said body portion to define said top surface portion thereof.
Claim 8
Dependent Claim
37 words
A transversal filter as set forth in claim 4, wherein said input and output transducers comprise a transducer pad having a plurality of electrode fingers extending therefrom in a lateral direction toward the edge of said ledge.
Claim 9
Dependent Claim
17 words
A transversal filter as set forth in claim 4, wherein said horizontal ledge has a wedge-shaped geometry.
References Cited (Backward Citations)
US3755761A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-10-24 | 1981-04-25 | 1981-10-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-10-24 | 1985-04-25 | 1985-10-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-10-24 | 1989-04-25 | 1989-10-25 | $7700.00 | Window Closed / Lapsed |