Dual-View Imaging of Laser-Induced Plasma Expansion at Varying Pressures

Using a prism-based dual-view setup, we observed laser-induced plasma expansion at varying pressures and energies. In this experiment, a pulsed Nd:YAG laser at 532 nm was focused through a plano-convex lens and fired at a carbon target of carbon within a vacuum chamber. This plasma was then imaged at different pressures and laser energies to observe plasma expansion using a combined high-speed camera and light intensifier setup. Pressures ranged from 100 millitorr to 760 torr and laser energies of 100-400 mJ. A mirror and prism setup was used to capture the side and front views of the plasma emissions at the same time in a split-screen. This was done using a set of five mirrors and a right-angle prism mirror to capture both split-screen views into one image. Split-screen images at various pressures and laser fluences were compared with each other to evaluate differences in plasma expansion. It was found that the plasma expansion was wider and more dispersed at lower pressures compared to higher pressures.