新型组合正轴棱锥产生局域空心光束

New combined positive axicon for generating bottle beam

提出了一种产生局域空心光束(Bottle beam)的新型光学元件,此元件由两个底面半径不等的正轴棱锥胶合而成,具有结构简单、容易加工等优点。研究了其沿径向分布不同部分光线的ABCD传输矩阵,通过几何光学分析了其产生Bottle beam的原理,数值模拟了平面波通过此新型光学元件后的纵向光场分布和沿轴向不同距离处的二维光斑图。为产生Bottle beam提出了一种新方法,对Bottle beam在光镊、光捕获等方面的应用有较好的指导意义。

A new type of optical element was proposed for generating bottle beam. This element glued two positive axicons with unequal radius of bottom flat surface. It had advantages of simple structure and easily being machined. The ABCD transfer matrix of the element in radial distribution was investigated. The principle of the bottle beam generated was analyzed by the geometrical optics. The longitudinal optical field distribution and 2D light spot image in different propagation distance behind new element were numerical simulated. A new way for generating bottle beam is proposed through the research results, it also shows the significant guidance for the practical applications of the bottle beam in the aspects of optical tweezers and optical capture.