Optical Detection and Analysis of Non-Linear Optoacoustic Waves

Abstract

Detection and analysis of optoacoustic waves, generated by interaction of high intensity pulsed laser beams with solid surfaces, have opened new possibilities in monitoring of laser induced damage [1–4] and laser manufacturing processes [5–7]. Several experimental studies [1–3] have pointed out the nonlinear nature of these waves. It has been shown recently [4], that some nonlinear features of laser induced OA waves in air can be explained using the point explosion model. This contribution discusses the results of the time and frequency domain analysis of finite amplitude OA waves, detected by a knife edge laser probe in air at normal atmospheric conditions. considering OA wave generation and propagation as a laser induced point explosion, acoustic energy and transfer function of the detection system are determined.