A Study On Thermal Effect Of Optical Materials Under Strong Laser Illumination

Since the laser has appeared, as countries continue to input, lasers and laser technology has been the development of more than fifty years.Now laser technology is almost applied in various natural disciplines, each field.As the field of laser application in real life is getting more and more broad.Laser technology is playing a more and more irreplaceable role.This paper mainly described the heat effect of laser irradiating targets around.Based on the physical model of the strong laser irradiating on optical materials,a more detailed description of the light propagation in medium and the mechanism of interaction between intense laser and optical materials is made. With Continuous Gauss beam irradiation,temperature and stress distribution of 2D and 3D cylindrical was calculated.By using finite difference method,a detailed analysis of the one and 2D finite difference format is done,compared with the COMSOL simulation results and literature.At last,a simulation software of laser irradiation to the target is developed with hybrid programming between Microsoft Visual C# and MATLAB.This major work and innovation are as follows:1.The mechanism of light and medium material is introduced. Combined with the Maxwell equations of electromagnetism,the absorption process of wave in the medium propagation is deduced in detail.From the microscopic point of view,analysis of the interaction between high power laser and materials including the intrinsic absorption, self focusing effect, electron avalanche and multiphoton ionization,impurities and defects, ultrasonic, nonlinear absorption.And the heat conduction process in the material irradiated by laser and the equation of heat conduction and thermal stress equationis is emphatically introduced.2.According to the heat transfer equation, the heat stress equation and integral transform method,temperature and stress distribution in optical material irradiated by Gauss beam is derived in 2D cylindrical coordinates compared with the literature.And on this basis,we get the 3D temperature and stress distribution with Neumann boundary condition,compared with the COMSOL simulation results.3.With the application of finite difference method,we get the 1D explicit difference of the thermal conductivity equation.Based on the one-dimensional implicit six point difference format,the alternating direction implicit difference format is obtained compared with the COMSOL simulation results.4.Combining the respective advantages of C# and MATLAB,build a laser irradiation optical material simulation software with the use of hybrid programming between C# and MATLAB.