Long Transmission Hollow Beams Produced Based On The Double Diffraction Optical Element Combination

Due to hollow beam has the unique property:the light intensity distribution present barrel, the size of the center of the dark spot look smaller, beam transmission is invariance, unique spin angular momentum and orbital angular momentum. So hollow beams are widely used in laser tube, optical wrench and scan. But in the long distance transmission process, it is used to appear the image distortion. At the same time when making some device for hollow beam transmission, it ask us for the precision of the lens must be too high, then it is difficult to get it large-scale application. So it is necessary that develop a new type of hollow beams which can be long-distance transmission.Based on the diffraction optical transmission theory and diffraction optical element,we design mechanism. Through the two pieces of diffraction optical element combinations we get hollow beam can be long-range transmission.At the same time, we proposed a modified of the beam shaping algorithm, and on the basis we get two pieces of optical element phase distribution and the simulation intensity distribution of the emergent hollow beam.Finally we get the long distance transmission simulation of the hollow beams. Through the improvement between in different distance of hollow beams with general positive and negative pyramid combination of hollow beam analysis, we prove that the improved hollow beams in the long distance transmission process is better, the intensity distribution image of the emergent light remains good, it also can be proved that this research on the development of hollow beams have progress.