Patent US3621765A successfully refreshed from Google Patents.
Patent US4837476A successfully refreshed from Google Patents.
US4837476A
Expired / Lapsed
US
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Surface acoustic wave resonator having transducers and reflectors of different periods
Assignee: Pioneer Corp
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Filing: 1986-04-28
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Granted: 1989-06-06
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Expires: 2006-04-28
Abstract
Abstract A surface acoustic wave resonator comprising at least two interdigital electro-acoustic transducers found between two sets of reflective gratings on a crystalline substrate. The period of the electrodes of the transducers is selected to be less than the period of the reflective gratings.
Inventors
- 👤 Masami Mochizuki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 06:48
CPC Classifications
H; H03; H03H; H03H9/00; H03H9/02; H03H9/02535; H03H9/02637; H03H9/02685
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
115 words
A surface acoustic wave resonator, comprising: a substrate of a crystal; a pair of surface wave reflectors formed on a crystal surface of said substrate and each comprising a plurality of reflection gratings; a plurality of electro-acoustic interdigital transducers formed on said substrate surface between said pair of reflectors and each having a plurality of electrodes; and a film covering only said pair of reflectors or only said plurality of transducers, thereby providing different propagation velocities, wherein a spatial propagation period L T1 of said electrodes of said interdigital transducers and a spatial propagation period L R1 of said gratings of said reflectors have values having a ratio L T1 /L R1 less than one.
Claim 2
Dependent Claim
115 words
A surface acoustic wave resonator, comprising: a substrate of a crystal; a pair of surface wave reflectors formed on a crystal surface of said substrate and each comprising a plurality of reflection gratings; a plurality of electro-acoustic interdigital transducers formed on said substrate surface between said pair of reflectors and each having a plurality of electrodes; and a film covering only said pair of reflectors or only said plurality of transducers, thereby providing different propagation velocities, wherein a spatial propagation period L T1 of said electrodes of said interdigital transducers and a spatial propagation period L R1 of said gratings of said reflectors have values having a ratio L T1 /L R1 less than one.
Claim 3
Dependent Claim
19 words
A resonator as recited in claim 1, wherein said film comprises aluminum oxide and covers said plurality of transducers.
Claim 4
Dependent Claim
19 words
A resonator as recited in claim 1, wherein said film comprises silicon oxide and covers said pair of reflectors.
Claim 5
Dependent Claim
25 words
A resonator as recited in claim 1, wherein said film is an insulator uniformly covering either said pair of reflectors or said plurality of conductors.
References Cited (Backward Citations)
US3883831A
Cited
US3886504A
Cited
US4065735A
Cited
US4155057A
Cited
US4472652A
Cited
US4243960A
Cited
US4425554A
Cited
US4427956A
Cited
US4617487A
Cited
US4635009A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1992-06-05 | 1992-12-05 | 1993-06-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1996-06-05 | 1996-12-05 | 1997-06-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2000-06-05 | 2000-12-05 | 2001-06-06 | $7700.00 | Window Closed / Lapsed |