US4491811A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Surface acoustic wave device
Assignee: Faurecia Clarion Electronics Co Ltd
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Filing: 1983-06-22
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Granted: 1985-01-01
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Expires: 2003-06-22
Abstract
Abstract A surface acoustic wave device in which first electrodes are provided on a piezoelectric film deposited on an elastic substrate, second electrodes between the piezoelectric film and the elastic substrate, and third electrode within the piezoelectric film, respectively, so that an electric signal is applied to the first and second electrodes.
Inventors
- 👤 Teruo Niitsuma
- 👤 Shoichi Minagawa
- 👤 Takeshi Okamoto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 13:21
CPC Classifications
H; H03; H03H; H03H9/00; H03H9/02; H03H9/125; H03H9/145; H03H9/14502; H03H9/14508; H03H9/02228
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
76 words
A surface acoustic wave device which comprises: an elastic substrate; a piezoelectric film deposited on said elastic substrate; input and output first electrodes both provided on said piezoelectric film; input and output second electrodes both provided between said piezoelectric film and said elastic substrate; third electrode provided within said piezoelectric film and between said first electrodes and said second electrodes; and a signal supply means applying an electric signal to the first and second input electrodes.
Claim 2
Dependent Claim
76 words
A surface acoustic wave device which comprises: an elastic substrate; a piezoelectric film deposited on said elastic substrate; input and output first electrodes both provided on said piezoelectric film; input and output second electrodes both provided between said piezoelectric film and said elastic substrate; third electrode provided within said piezoelectric film and between said first electrodes and said second electrodes; and a signal supply means applying an electric signal to the first and second input electrodes.
Claim 3
Dependent Claim
37 words
A surface acoustic wave device as set forth in claim 1 wherein said first and second electrodes are disposed at a predetermined positional lag in a direction to propagate a surface acoustic wave generated in said device.
Claim 4
Dependent Claim
37 words
A surface acoustic wave device as set forth in claim 2 wherein said lag is (θ-π)λ 0 /2π (λ 0 is wavelength of the surface acoustic wave, and θ is a phase difference of the electric signal).
Claim 5
Dependent Claim
19 words
A surface acoustic wave device as set forth in claim 2 wherein said electric signal has 90° phase difference.
Claim 6
Dependent Claim
19 words
A surface acoustic wave device as set forth in claim 1 wherein said electric signal has 180° phase difference.
Claim 7
Dependent Claim
22 words
A surface acoustic wave device as set forth in claim 1 wherein said third electrode is connected to an earth potential point.
Claim 8
Dependent Claim
40 words
A surface acoustic wave device as set forth in claim 1 wherein said first and second electrodes each have plural electrode fingers which are wide and spaced as much as one half of the wavelength of the surface acoustic wave.
Claim 9
Dependent Claim
21 words
A surface acoustic wave device as set forth in claim 7 wherein said first and second electrodes have a same configuration.
Claim 10
Dependent Claim
25 words
A surface acoustic wave device as set forth in claim 3 wherein said lag in one forth of the wavelength of said surface acoustic wave.
Claim 11
Dependent Claim
21 words
A surface acoustic wave device as set forth in claim 1 wherein said elastic substrate is made of a semiconductive material.
References Cited (Backward Citations)
US3955160A
Cited
US4354130A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-01-01 | 1988-07-02 | 1989-01-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-01-01 | 1992-07-02 | 1993-01-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-01-01 | 1996-07-02 | 1997-01-01 | $7700.00 | Window Closed / Lapsed |