Simulation Of Self-focusing Phenomenon Of High-power Laser Based On Iterative Ray-Tracing

With the constant development and popularized application of High-Power Laser, nonlinear self-focusing effect has become one of the focuses of research. In this paper, a simulation method of self-focusing based on iteration and ray-tracing is presented. The simulation result of this method accords well with the result of previous mature methods.The method presented solves the problem of inhomogeneous refractive index media by "cutting" it into massive slices and solves the problem of unknown parameters in solving the ray equation by iteration. Moreover, a modeling method of optical system based on element by which we analyze an actual high-power laser system is presented, the result meets expectation. In addition, a simulation method based on Winger Distribution Function is presented and the simulation result meets expectation.Compared with Beam Propagation Method, the advantages of methods based on ray-tracing that it works well with linear propagation and gives a intuitive vision of propagation make it more suitable for engineering applications. Also, this method is more precise when off-axis rays are involved because no paraxial approximations are applied. Compared with other methods based on ray-tracing, the method presented offers a different way, which does not change key equations, to solve key problems in simulation, thus lifts the limit of accuracy.Simulation of nonlinear self-focusing phenomenon of high-power laser is a significant guild of applications. For a large high-power laser system, both the unexpected damage brought by small-scale self-focusing and the beam quality reduction of target surface are severe problems of the designing, setting and functions. For a laser beam propagating in atmosphere, it has great significance for applications such as laser radar to research the filament effectIn summary, a simulation method of self-focusing, the combination of linear tracing and nonlinear tracing, a modeling method based on element which improves the efficiency and accuracy of design and an attempt to apply Wigner Distribution Function to nonlinear optics and presented as research works of this paper.