Sonic velocity measurement by using Bragg reflection detection technique based on optical feedback effects for laser diode

Summary form only given. Ultrasonic spectroscopy, which is defined as the velocity and/or absorption measurement as a function of frequency, has been recognized as one of the methods for investigating the dynamical properties of liquids and solids. In this paper, we propose an ultrasonic measurement technique by using a Bragg reflection detection instrument that is based on optical feedback effects for a laser diode (LD).