US3601639A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Low-temperature coefficient lithium tantalate resonator
Assignee: AT&T Inc
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Filing: 1970-01-09
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Granted: 1971-08-24
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Expires: 1990-01-09
Abstract
Abstract Length extensional mode and width-length flexure mode resonators fabricated from lithium tantalate piezoelectric single crystals cut to have orientations within the range of zyw (+25*) to zyw (+50*) exhibit zero temperature coefficients of frequency, thus permitting their use as resonators in wideband crystal filters and voltage controlled oscillators.
Inventors
- 👤 John J Hannon
- 👤 Peter Lloyd
- 👤 Robert T Smith
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 22:15
CPC Classifications
H; H03; H03H; H03H9/00; H03H9/02; H03H9/02007; H03H9/02015; H03H9/02031
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
54 words
An electrical device including a piezoelectric single crystal resonator of length 1, said resonator having at least two opposite parallel faces of length 1, and at least two electrodes attached to said faces, characterized in that said crystal consists essentially of lithium tantalate having an orientation within the range zyw +25* to zyw +50*.
Claim 2
Dependent Claim
54 words
An electrical device including a piezoelectric single crystal resonator of length 1, said resonator having at least two opposite parallel faces of length 1, and at least two electrodes attached to said faces, characterized in that said crystal consists essentially of lithium tantalate having an orientation within the range zyw +25* to zyw +50*.
Claim 3
Dependent Claim
14 words
The device of claim 1 in which all of the crystal faces are rectangular.
Claim 4
Dependent Claim
16 words
The device of claim 1 in which said crystal resonates in the fundamental length extensional mode.
Claim 5
Dependent Claim
20 words
The device of claim 3 in which said crystal has an orientation within the range zyw +35* to zyw +50*.
Claim 6
Dependent Claim
23 words
The device of claim 3 in which the width w of the crystal is up to one-half the length 1 of the crystal.
Claim 7
Dependent Claim
18 words
The device of claim 1 in which said crystal resonates in an overtone of the length extensional mode.
Claim 8
Dependent Claim
15 words
The device of claim 1 in which said crystal resonates in the width-length flexure mode.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-08-23 | 1975-02-22 | 1975-08-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-08-23 | 1979-02-22 | 1979-08-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-08-23 | 1983-02-22 | 1983-08-24 | $7700.00 | Window Closed / Lapsed |