轴棱锥椭圆加工误差产生畸变无衍射光束的修正

轴棱锥的斜入射和加工误差对产生零阶贝塞耳光的光束质量有很大影响,而轴棱锥的加工误差常常是轴棱锥圆形横截面被加工成椭圆.由衍射理论和几何光学方法出发,分析了圆轴棱锥的斜入射和椭圆轴棱锥的正入射对产生贝塞耳光束质量影响的等价性.根据理论计算,模拟了圆轴棱锥的斜入射和椭圆轴棱锥加工误差的衍射光斑图.提出利用轴棱锥旋转法修正椭圆轴棱锥对无衍射贝塞耳光束质量的影响,获得了近似理想的贝塞耳光束,理论分析与模拟和实验结果基本相符.

Modification of Aberration Nondiffraction Beams in Manufacture Error of Elliptical Axicon

Beam′s oblique incidence and manufacture error of an axicon have a great influence on the quality of zero-order Bessel beams. Generally, the manufacture error is that the cross section of the axicon is not a circle but an ellipse. Based on the diffraction and geometry optics, the quality equivalence between the beam′s oblique incidence in a circular axicon and beams incidence in vertical angle in an elliptical axicon are analyzed. The diffractive optical patterns in oblique illumination on a circular axicon and the manufacture error in an elliptical axicon were simulated according to the calculation. The method to modify the influence on the nondiffraction Bessel beam of an elliptical axicon by rotating the axicon is proposed and the approximately perfect Bessel beams are obtained. The experimental result agrees with the theoretical analysis and numerical simulation.