US4541280A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Efficient laser generation of surface acoustic waves
Assignee: National Research Council Canada
•
Filing: 1982-12-28
•
Granted: 1985-09-17
•
Expires: 2002-12-28
Abstract
Abstract The surface acoustic waves are generated by laser beam that is focussed onto a surface to irradiate it in an arcuate pattern as a partial annulus or as a still or moving fringe pattern. The arcuate pattern may be formed by a transmitting or a reflecting axicon, while the fringe pattern may be formed by splitting the laser beam into two beams and directing the two beams to the surface. In addition, a lens or a frequency shifting device may be placed in the path of one of the split beams to form a circular fringe or a moving fringe, respectively.
Inventors
- 👤 Paolo G. Cielo
- 👤 Jean Bussiere
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 15:50
CPC Classifications
G; G01; G01N; G01N29/00; G01N29/22; G01N29/24; G01N29/2418; G10; G10K; G10K15/00; G10K15/04; G10K15/046; G01N2291/00; G01N2291/04; G01N2291/042; G01N2291/0422; G01N2291/0423; G01N2291/0426
Claims Analysis
Total Claims: 16
Claim 1
Independent Claim
41 words
A method of generating surface acoustic waves on a surface comprising: providing a laser generated optical beam; directing the beam to the surface; and focusing the beam into an annulus irradiated pattern on the surface to form a converging surface wave.
Claim 2
Independent Claim
41 words
A method of generating surface acoustic waves on a surface comprising: providing a laser generated optical beam; directing the beam to the surface; and focusing the beam into an annulus irradiated pattern on the surface to form a converging surface wave.
Claim 3
Dependent Claim
15 words
A method as claimed in claim 1 in which the annulus is a partial annulus.
Claim 4
Dependent Claim
40 words
Apparatus for generating acoustic surface waves on a surface comprising: laser means for generating a coherent beam of optical energy; and means for focusing the beam onto the surface in an annulus irradiated pattern to form a converging surface wave.
Claim 5
Dependent Claim
40 words
Apparatus for generating acoustic surface waves on a surface comprising: laser means for generating a coherent beam of optical energy; and means for focusing the beam onto the surface in an annulus irradiated pattern to form a converging surface wave.
Claim 6
Dependent Claim
14 words
Apparatus as claimed in claim 3 wherein the annulus pattern is a partial annulus.
Claim 7
Dependent Claim
21 words
Apparatus as claimed in claim 3 or 4 wherein the focusing means includes an axicon lens located on the beam path.
Claim 8
Dependent Claim
23 words
Apparatus as claimed in claim 3 or 4 wherein the focusing means includes an axicon reflector for reflecting the beam to the surface.
Claim 9
Independent Claim
46 words
A method of generating acoustic waves on a surface comprising: providing a laser generated optical beam; splitting the beam into two beams; directing the beams to the surface; and focusing the beams to form a fringe pattern on the surface to form a converging surface wave.
Claim 10
Independent Claim
46 words
A method of generating acoustic waves on a surface comprising: providing a laser generated optical beam; splitting the beam into two beams; directing the beams to the surface; and focusing the beams to form a fringe pattern on the surface to form a converging surface wave.
Claim 11
Dependent Claim
27 words
A method as claimed in claim 7 which includes: shifting the frequency of one of the two beams such that the fringe pattern moves on the surface.
Claim 12
Dependent Claim
55 words
Apparatus for generating acoustic surface waves on a surface comprising: laser means for generating a coherent beam of optical energy; beam splitter means for splitting the beam into two beams; and reflector means for deflecting the two beams onto the surface to form a fringe pattern on the surface to form a converging surface wave.
Claim 13
Dependent Claim
55 words
Apparatus for generating acoustic surface waves on a surface comprising: laser means for generating a coherent beam of optical energy; beam splitter means for splitting the beam into two beams; and reflector means for deflecting the two beams onto the surface to form a fringe pattern on the surface to form a converging surface wave.
Claim 14
Dependent Claim
21 words
Apparatus as claimed in claim 9 which further includes a lens located in the path of one of the two beams.
Claim 15
Dependent Claim
22 words
Apparatus as claimed in claim 10 which further includes frequency shifting means located in the path of one of the two beams.
Claim 16
Dependent Claim
22 words
Apparatus as claimed in claim 9 which further includes frequency shifting means located in the path of one of the two beams.
References Cited (Backward Citations)
US4121470A
Cited
US4169662A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-09-16 | 1989-03-18 | 1989-09-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-09-16 | 1993-03-18 | 1993-09-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-09-16 | 1997-03-18 | 1997-09-17 | $7700.00 | Window Closed / Lapsed |