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US3984791A
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Acoustic surface wave filters having bifurcated members with connecting links
Assignee: Plessey Handel und Investments AG
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Filing: 1975-06-24
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Granted: 1976-10-05
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Expires: 1995-06-24
Abstract
Abstract An acoustic surface wave filter which includes a strip member of a piezoelectric material having input and output interdigital transducers formed on a major surface thereof, each of the interdigital transducers including two interlaced rows of parallel spaced-apart elongated members, each of the elongated members of at least one of the rows being bifurcated to provide two parallel limbs, the limbs of each of the bifurcated members being connected together by means of at least one connecting link.
Inventors
- 👤 John Maxwell Deacon
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 23:05
CPC Classifications
H; H03; H03H; H03H9/00; H03H9/02; H03H9/125; H03H9/145; H03H9/14544; H03H9/14552; H03H9/02535; H03H9/02818; H03H9/02842; H03H9/0285; Y; Y10; Y10T; Y10T29/00; Y10T29/42
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
90 words
An acoustic surface wave filter which includes a strip member of a piezoelectric material having input and output interdigital transducers formed on a major surface thereof, each of the interdigital transducers including two interlaced rows of parallel spaced-apart elongated members, each of the elongated members of at least one of the rows being bifurcated to provide two parallel limbs, the limbs of each of the bifurcated members being connected together by means of at least one connecting link of a material different from the piezoelectric material of said strip member.
Claim 2
Dependent Claim
90 words
An acoustic surface wave filter which includes a strip member of a piezoelectric material having input and output interdigital transducers formed on a major surface thereof, each of the interdigital transducers including two interlaced rows of parallel spaced-apart elongated members, each of the elongated members of at least one of the rows being bifurcated to provide two parallel limbs, the limbs of each of the bifurcated members being connected together by means of at least one connecting link of a material different from the piezoelectric material of said strip member.
Claim 3
Dependent Claim
30 words
An acoustic surface wave filter as claimed in claim 1 wherein the free ends of the limbs of each of the bifurcated members are connected together by the connecting link.
Claim 4
Dependent Claim
33 words
An acoustic surface wave filter as claimed in claim 1 wherein the limbs of each of the bifurcated members are connected together by the connecting link at a position along the length thereof.
Claim 5
Dependent Claim
16 words
An acoustic surface wave filter as claimed in claim 1 wherein the piezoelectric material is quartz.
Claim 6
Dependent Claim
36 words
An acoustic surface wave filter as claimed in claim 1 wherein the limbs of each of said bifurcated members are conductively connected together by means of at least one connecting link of an electrically conductive material.
Claim 7
Dependent Claim
26 words
An acoustic surface wave filter as claimed in claim 1 wherein the elongated members of each of the rows are bifurcated to provide two parallel limbs.
Claim 8
Dependent Claim
33 words
An acoustic surface wave filter as claimed in claim 6 wherein the limbs of each of the bifurcated members are connected together by the connecting link at a position along the length thereof.
Claim 9
Dependent Claim
30 words
An acoustic surface wave filter as claimed in claim 6 wherein the free ends of the limbs of each of the bifurcated members are connected together by the connecting link.
References Cited (Backward Citations)
US3768032A
Cited
US3727155A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1979-10-05 | 1980-04-05 | 1980-10-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1983-10-05 | 1984-04-05 | 1984-10-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1987-10-05 | 1988-04-05 | 1988-10-05 | $7700.00 | Window Closed / Lapsed |