The Design Of Electromagnetic Devices Based On The Principle Of Microwave And Ray Tracing

Based on Maxwell’s equations,this thesis focuses on the design of devices for electromagnetic optics by using the theories for microwaves and ray optics.More specifically,the design background of such devices and the basic theories of microwaves and optics are presented,and three different approaches,ray optics,transformation optics,dispersion equations,are employed in the design process to enrich the device variety and design methods.The ideas are as follows.First,a method for solving the refractive index of a medium with a spherical symmetry distribution is introduced from the theory of ray optics.Inspired by this method,a circular curve cluster is designed.Then,the refractive index distribution of Maxwell fish-eye lens is obtained by analyzing this cluster and the detailed analyzing process is given.According to the characteristics of the designed curve cluster,a possible application of the fish-eye lens is also proposed.This work further develops the theoretical basis and the application prospect of the fish-eye lens.Second,a one-way invisible electromagnetic wave concentrator is designed by introducing the concept of PT symmetry in quantum mechanics into the theory of transformation optics,and the working mechanism of this concentrator is also discussed.This kind of concentrator with one-way invisibility expands the types of existing concentrators,and possibly could be further explored to applications such as wireless charging.Third,a new design method for multidirectional cloaks is proposed by applying dispersion equations of anisotropic materials to manipulate light paths.The cloaks designed by this method can be fabricated using natural anisotropic crystals.Theoretically,this design method has infinite solutions,and one of the feasible solutions is presented to illustrate the design process.In sum,this method provides a practical and feasible new choice for the design and fabrication of cloaks and makes the cloaks a step forward for practical applications.This thesis has theoretical and practical values for the design and implementation of new electromagnetic devices.