Laser Beam Shaping Based on Liquid Crystal Spatial Light Modulator
|School||Dalian University of Technology|
|Course||Signal and Information Processing|
|Keywords||Beam shaping A liquid crystal spatial light modulator The cover teacher Berger - Isaac Stone algorithm PMA- smooth correction hybrid algorithm|
The laser beam emitted light intensity Gaussian distribution , the propagation path of the hyperbolic nature largely restricts the application and development of laser technology . For example : in the processing of some semiconductor flattened beam can be improved laser energy processing window thereby improving efficiency ; in laser projection printing requires uniform light intensity ; , far field light source requires a uniform illumination in the laser radar and the coherent imaging . Gaussian laser beam shaping space , upcoming Gaussian beam shaping for the flat-top beam . This article using a liquid crystal spatial light modulator , the beam shaping , by changing the phase function of the liquid crystal spatial light modulator to achieve real time shaping of the Gaussian beam , is a controllable and efficient beam shaping method . The content of this article can be divided into the following aspects : First , the analysis of a typical beam shaping technology in the field of laser shaping , and compare their advantages and disadvantages . The development status and working principle of the liquid crystal spatial light modulator , summarize the advantages of using a liquid crystal spatial light modulator for beam shaping . Second, the study of a liquid crystal spatial light modulator phase function design principle and common optimization iterative algorithm , PMA- smooth Berg - Isaac Stone cover division algorithm based on modified hybrid algorithm , reducing the output beam top of the unevenness and the root mean square error , and using the algorithm to complete the design of the liquid crystal spatial light modulator the phase function . Again, the design and completed based on the liquid crystal spatial light modulator a beam shaping experiment . This article using a liquid crystal spatial light modulator the phase modulation characteristics , combined with the PMA- smoothing correction hybrid algorithm designed experimental optical path , optical experiment , to achieve a Gaussian beam intensity shaping near \using a liquid crystal spatial light modulator for beam shaping, the beam shaping is an effective method .