Abstract
The Cavitation reduces the performance of the fluid device. When the cavitation bubbles collapse, it will causes the shock wave and sometimes causes the micro-jet towards the wall. We visualized the laser-induced bubbles using BOS(Background Oriented Schlieren) method. The BOS technique is one of the visualization techniques, which enable us to perform experiments with simple optical system, and it requires a high-speed camera, a background image and a light source across to illuminate a background. The principle of BOS technique is similar to conventional Schlieren technique. As a result we have been able to visualize the density information of the shock wave induced by laser.