Visualization of Femtosecond Laser-Induced Underwater Micro Shock Waves

― Visualization of High-Speed Phenomena in Micro Scale ―

Abstract

Our group has been studying the fundamental phenomena of micro-shock waves generated by femtosecond laser-induced shock waves to utilize them as effective microscale stimulation for regenerating tissue cells. By now, we have confirmed that micro-shock waves are generated in liquid by optical focusing of a femtosecond laser. And we also visualized them by using a high-speed camera to investigate the wavefront structure and generated compression waves around the focus (plasma emission). Thus, we have been observing micro shock waves and bubble behavior. In this paper, we introduce some of the research that our group has conducted to date, and then introduce visualization methods for observing the propagation behavior of shock wavefront that accompanies the initial generation of femtosecond laser-induced underwater shock waves. In addition, we also introduce the information that can be obtained from the images.