Optical Detection of Sub-Angstrom Transient Mechanical Displacements

Detection of Leaky-Rayleigh Waves at Air-Solid Interfaces by Laser Interferometry

“…In order to detect the propagation of the ultrasonic pulses, a broad band electronic processing, similar to that used in the displacement measurements has been used in this experiment [12,13].…”

Measurement by Laser Generated Ultrasound of the Stiffness Tensor of an Anisotropic Material at Elevated Temperatures

“…In those conditions, ablation occurs at the sample surface, and marks it slightly. The LASER interferometric probe for the detection is a Mach-Zehnder, heterodyne type [2]. The bandwidth extends from 200 kHz to 18 MHz, and the sensitivity is 10 my/A.…”

“…= 0 (2) where to is the group time measured in direction t?, and p is the projection on the interface of the phase slowness in direction f}p. In Eq. 2, X stands for the unknown coefficients vector.…”

Three Ultrasonic Devices for the Elastic Moduli Determination at High Temperatures

“…The experimental set-up is composed of a Q-switched Nd:Yag laser operating at the wavelength of 1.064 ttm and of a Mach-Zehnder heterodyne interferometer [6] (Figure 3). The probe is sensitive to out-of-plane displacement and its large bandwidth extends from 20 kHz to 30 MHz with a sensitivity less than 10.…”