US4388599A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Piezoelectric elastic-wave convolver device
Assignee: Thales SA
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Filing: 1981-05-18
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Granted: 1983-06-14
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Expires: 2001-05-18
Abstract
Abstract A convolver based on the propagation of acoustic waves at the surface of a piezoelectric solid comprises a piezoelectric substrate, means for exciting two backward-traveling acoustic waves at the frequency f, means consisting of at least two electrodes for collecting the signal at the frequency 2f, the signal being produced as a result of nonlinear interaction of the two acoustic waves. The convolver device is connected to one of the two electrodes by means of a plurality of electrical contacts placed lengthwise and at intervals along the axis of propagation of the two interacting acoustic waves which are representative of the electrical signals applied to the two convolver inputs.
Inventors
- 👤 Herve Gautier
- 👤 Charles Maerfeld
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 17:37
CPC Classifications
G; G06; G06G; G06G7/00; G06G7/12; G06G7/19; G06G7/195
Claims Analysis
Total Claims: 41
Claim 1
Independent Claim
97 words
A convolver device based on the propagation of acoustic waves at the surface of a piezoelectric solid and comprising: a piezoelectric substrate, means for exciting two backward-traveling acoustic waves at the frequency f, means consisting of at least two electrodes for collecting the signal at the frequency 2f, said signal being produced as a result of the nonlinear interaction of the two acoustic waves, wherein the output of said device is connected to one of said electrodes by means of a plurality of electrical contacts placed lengthwise along the axis of propagation of the two acoustic waves.
Claim 2
Dependent Claim
97 words
A convolver device based on the propagation of acoustic waves at the surface of a piezoelectric solid and comprising: a piezoelectric substrate, means for exciting two backward-traveling acoustic waves at the frequency f, means consisting of at least two electrodes for collecting the signal at the frequency 2f, said signal being produced as a result of the nonlinear interaction of the two acoustic waves, wherein the output of said device is connected to one of said electrodes by means of a plurality of electrical contacts placed lengthwise along the axis of propagation of the two acoustic waves.
Claim 3
Dependent Claim
31 words
A convolver device according to claim 1, wherein said device comprises means for spatial compression of the two acoustic waves and wherein the electrode connected to the output forms a waveguide.
Claim 4
Dependent Claim
48 words
A convolver device according to claim 2, wherein the spacing between the contacts is chosen so as to have a small value in comparison with the electromagnetic wavelength λ EM equal to v EM /2f where v EM is the velocity of the electromagnetic waves within the guide.
Claim 5
Dependent Claim
44 words
A convolver device according to claim 2, wherein the spacing between the contacts is chosen so as to ensure that the product of resistance and capacitance of the waveguide portions between two contacts is of sufficiently low value in comparison with the period 1/s.
Claim 6
Dependent Claim
25 words
A convolver device according to claim 2, wherein the electrode connected to the output is a metallization layer deposited on the surface of the substrate.
Claim 7
Dependent Claim
57 words
A convolver device according to claim 5, wherein the electrical contacts are formed directly on the waveguide by welding or by bonding, the dimension of the weld spot or bonding spot connection being smaller than 0.1 times the acoustic wavelength λ a equal to v a /2f, where v a is the velocity of the acoustic waves.
Claim 8
Dependent Claim
16 words
A convolver device according to claim 6, wherein the weld spot connection is obtained by thermocompression.
Claim 9
Dependent Claim
17 words
A convolver device according to claim 6, wherein the weld spot connection is obtained by ultrasonic vibrations.
Claim 10
Dependent Claim
21 words
A convolver device according to claim 6, wherein the bonding operation is carried out with indium or with conductive epoxy resin.
Claim 11
Dependent Claim
18 words
A convolver device according to claim 5, wherein the electrical contacts extend laterally with respect to the waveguide.
Claim 12
Dependent Claim
49 words
A convolver device according to claim 10, wherein metallic chips extending alongside the waveguide are deposited in recesses in order to receive the electrical contacts and are joined to the waveguide by means of first metallic strips, the width of said first strips being smaller than λ a /5.
Claim 13
Dependent Claim
31 words
A convolver device according to claim 11, wherein the connection chips are joined to the first strips by means of strips which increase in width at a distance from the waveguide.
Claim 14
Dependent Claim
34 words
A convolver device according to claim 12, wherein said device comprises a thin film of insulating material between the surface of the piezoelectric substrate and the assembly consisting of widened strips and connection chips.
Claim 15
Dependent Claim
27 words
A convolver device according to claim 1, wherein said device comprises two ground electrodes deposited at the surface of the substrate on each side of the waveguide.
Claim 16
Dependent Claim
24 words
A convolver device according to claim 11, wherein each electrical contact is associated with two connection chips placed on each side of the waveguide.
Claim 17
Dependent Claim
29 words
A convolver device according to claim 11, wherein said device comprises ground electrodes deposited on the surface of the substrate, said ground electrodes being recessed around each connection chip.
Claim 18
Dependent Claim
19 words
A convolver device according to claim 11, wherein the first strips are deposited on the surface of the substrate.
Claim 19
Dependent Claim
26 words
A convolver device according to claim 11, wherein the first strips are in the form of stirrup-pieces whose ends rest on the surface of the substrate.
Claim 20
Dependent Claim
35 words
A convolver device according to claim 10, wherein the contacts are formed by one of the following means: welding by thermocompression, welding by ultrasonic vibrations, bonding with indium and bonding with electrically conductive epoxy resin.
Claim 21
Dependent Claim
37 words
A convolver device according to claim 2, wherein the dimensions of the electrode which is connected to the output are similar to those of the waveguide, said electrode being located at a predetermined distance above said waveguide.
Claim 22
Dependent Claim
47 words
A convolver device according to claim 20, wherein said device comprises a second substrate applied to the surface of the first substrate which supports the waveguide and wherein a recess is formed in said second substrate and fitted with the electrode which is connected to the output.
Claim 23
Dependent Claim
79 words
A convolver device according to claim 21, wherein the depth of the recess is chosen so as to ensure that the distance h between the waveguide and the electrode which is connected to the output is considerably smaller than W/ε p , where W is the width of the waveguide and ε p is the relative permittivity of the substrate, and permits a capacitive coupling between said waveguide and said output-connected electrode without impairing the efficiency of the convolver.
Claim 24
Dependent Claim
40 words
A convolver device according to claim 21, wherein the contact faces of the first and second substrate are polished and then held together either by bonding or by mechanical pressing or by adhesion obtained by means of an optical joint.
Claim 25
Dependent Claim
32 words
A device according to claim 20, wherein a recess is formed in the first substrate and fitted with the waveguide, a second substrate being applied to the surface of the first substrate.
Claim 26
Dependent Claim
30 words
A convolver device according to claim 21, wherein the acoustic wave guide is formed by depositing a metallization layer on the surface of the first substrate over the width W.
Claim 27
Dependent Claim
25 words
A convolver device according to claim 21, wherein the waveguide is formed by means of an overthickness of the first substrate having a width W.
Claim 28
Dependent Claim
30 words
A convolver device according to claim 21, wherein the waveguide is formed by modifying the structure of the surface of the first substrate over the width W by ion implantation.
Claim 29
Dependent Claim
65 words
A convolver device according to claim 5, wherein the waveguide is shaped in thickness transversely to the axis of propagation of the acoustic waves so as to have a central zone of greater thickness having a width W and at least one lateral zone of smaller thickness, the electrical contacts being formed at the level of the outer edges of the lateral zone or zones.
Claim 30
Dependent Claim
28 words
A convolver device according to claim 28, wherein shaping of the waveguide is performed by overlaying a material having a width W on a metallization layer previously formed.
Claim 31
Dependent Claim
19 words
A convolver device according to claim 28, wherein shaping of the waveguide is performed by machining the metallization layer.
Claim 32
Dependent Claim
30 words
A convolver device according to claim 28, wherein the waveguide is shaped so as to have two lateral zones having the same width on each side of the central zone.
Claim 33
Dependent Claim
60 words
A convolver device according to claim 5, wherein the waveguide is formed of a full central zone having a width W for guiding the waves and of at least one recessed lateral zone having the same thickness and constituted by strips extending away from the axis of the waveguide, the electrical contacts being formed at the ends of said strips.
Claim 34
Dependent Claim
20 words
A convolver device according to claim 32, wherein the relative spacing of the strips does not exceed λ a /2.
Claim 35
Dependent Claim
21 words
A convolver device according to claim 32, wherein said device comprises a lateral zone on each side of the central zone.
Claim 36
Dependent Claim
38 words
A convolver device according to claim 28, wherein the electrical contacts are formed by one of the following means: welding by thermocompression, welding by ultrasonic vibrations, bonding with indium and bonding by means of electrically conductive epoxy resin.
Claim 37
Dependent Claim
23 words
A convolver device according to claim 28, wherein the electrical contacts consist of chips formed by metallization at the surface of the substrate.
Claim 38
Dependent Claim
25 words
A device according to claim 28, wherein the metallized chips are separated from the surface of the substrate by a thin film of insulating material.
Claim 39
Dependent Claim
22 words
A convolver device according to claim 5, wherein metallization is obtained as a result of deposition performed by evaporation of the metal.
Claim 40
Dependent Claim
22 words
A convolver device according to claim 5, wherein metallization is obtained as a result of deposition performed by sputtering of the metal.
Claim 41
Dependent Claim
32 words
A device according to claim 2, wherein the electrical contacts are connected to the output by means of tracks of equal length of a printed circuit placed in proximity to the substrate.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-06-13 | 1986-12-13 | 1987-06-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-06-13 | 1990-12-13 | 1991-06-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-06-13 | 1994-12-13 | 1995-06-14 | $7700.00 | Window Closed / Lapsed |