Dual-beam interferometer for the accurate determination of surface-wave velocity
Abstract
A novel dual-beam interferometer has been designed and constructed that enables two beams from an He-Ne laser to probe remotely the surface of a material. The separation of the two He-Ne beams is adjustable in the 15-40-mm range with a spatial resolution of 2 microns. SAW measurements have been performed with two different probe separations so that the travel time for the surface waves over a known distance can be determined accurately. With the aid of autocorrelation algorithms, the Rayleigh pulse velocity on 7075-T651 aluminum has been measured to be 2888 +/-4 m/s.
- Publication:
-
Applied Optics
- Pub Date:
- October 1991
- DOI:
- 10.1364/AO.30.004034
- Bibcode:
- 1991ApOpt..30.4034M
- Keywords:
-
- Helium-Neon Lasers;
- Laser Beams;
- Laser Interferometry;
- Rayleigh Waves;
- Surface Waves;
- Velocity Measurement;
- Elastic Anisotropy;
- Nondestructive Tests;
- Q Switched Lasers;
- Wave Attenuation;
- Instrumentation and Photography;
- INTERFEROMETRY;
- PHOTOACOUSTICS;
- NONDESTRUCTIVE TESTING;
- ULTRASOUND