The Special Beam Generator Based On The Micro-structure

With expansion of the application fields and the constant development of laser technology,special laser beams have great important applications in laser capture,optical microoperation,atomic optics,laser processing and other fields.It has become an emerging field.Therefore,it is of importance to study the control of the incident light field to produce the special beam generator with special shape of light field distribution.In this paper,two kinds of special beam generator with micro-structure based on the surface plasmon and the whole dielectric resonance are designed.The difference between this kind of beam generator and those designed in the past is that the structure of the former one is designed on the end face of the optical fiber.And this enable the special light beam generator to own many characteristics,such as spatial alignment and coupling without strict,high integration,flexible operation,system stability and strong anti-interference ability etc.The main contents are as follows:1.Introduce the basic theory,generated conditions and methods of Airy beams.According to the surface plasmon properties of micro-structure,through the finite element software to design a single Airy beam generator,and the simulation results are analyzed to optimize the structure,and further analyze the affection on simulation results when this single Airy beam generator is immersed in liquid with different refractive index.Based on the single Airy beam generator,double Airy beam generator is proposed and symmetrical structure double Airy beam generator and asymmetric one are designed respectively.And the characteristics of two kinds of double Airy beam generators are analyzed in the transmission process,and the distribution of electric field in the far field focusing is also studied.On top of this,the effect of air groove depth and spacing of two air seam on the focusing phenomenon of double symmetric structure Airy beam generator are studied.The influence of different initial phase difference on the focusing phenomenon of asymmetrical structure double Airy beam generator is also researched.2.Introduce the theoretical basis of focused beam and its generation method.According to the surface plasmon properties of the micro-structure,using finite element software to design a single light beam generator,verify the validity of the structure.To design a double beam generator with different focal length in the basis of single focused beam,analyze its structure and then propose the optimization plan.In accordance with all dielectric resonant of micro-structure,design a single focused light beam generator,analyze its simulation results and summarize advantages and disadvantages of the two methods respectively.