Abstract
Laser-generated high-frequency surface acoustic waves (SAWs) and their optical detection for noncontact and nondestructive materials evaluation were presented. Scanning interference fringes (SIF) produced by intersecting two coherent pulsed laser beams on a tested object with different frequencies were used as a thermoelastic source to generate a 110 MHz SAW. The SAW was detected by the optical knife edge method using another continuous wave (CW) laser as a probe beam. Estimation of the SAW amplitude was carried out and the amplitude enhancement effect of the phase velocity scanning (PVS) method was verified. As a result, the SAW amplitude of 1.4 nm was obtained on an aluminum specimen with 0.71 MW/cm2power density of second-harmonic waves (532 nm) of a Q-switched Nd:YAG laser. An application to anisotropic SAW velocity measurement on a silicon (100) surface was carried out.
| Original language | English |
|---|---|
| Pages (from-to) | 3260-3264 |
| Number of pages | 5 |
| Journal | Japanese journal of applied physics |
| Volume | 33 |
| Issue number | 5S |
| DOIs | |
| Publication status | Published - 1994 May |
| Externally published | Yes |
Keywords
- Elastic anisotropy
- Fringe
- Laser-generated ultrasounds
- Nondestructive evaluation
- Optical knife edge method
- Phase velocity scanning method
- Scanning interference
- Surface acoustic waves
- Thermoelastic effect
ASJC Scopus subject areas
- Engineering(all)
- Physics and Astronomy(all)