Abstract: Photoelastic visualization is a method by which ultrasonic field in transparent solids can be effectively observed.
In the present paper, we briefly discribe the basic principles of this method and show the experimental apparatus used in our laboratory and some ultrasonic filed photos taken in a transparent medium. Furthermore, a simple method is introduced, which can be conveniently used to measure the stress distribution in solids by a system of linearly polarized light. In this way we, had overcome some difficulties when we quantitatively measured the ultrasonic fields scattered by a cylindical cavity embeded in a glass sample.