| Abstract: | A flow field induced by pulsed laser ablation of several target materials in air was observed by high-speed photography. Two Nd:YAG lasers were used in this study, one as an energy source and the other as a light source. Propagation of produced shock wave front in the early stage was visualized by the laser shadowgraphy technique. We found an appreciable density variation after about 100 7s of laser irradiation. We have tested the targets of several kinds of metals, silicon, and graphite, and observed the same phenomena at a similar delay time. This dark shadow region seems to represent the cloud of nanoparticles produced by ablated materials, which can be collected on a glass plate. |
