基于轴棱锥的新型光学元件设计及其特性研究

【作者】 马亮；

【导师】 吴逢铁；

【作者基本信息】 华侨大学 ， 光学， 2011， 硕士

【摘要】 学位论文设计了几种新型光学元件,包括新型锥透镜、阶变折射率轴棱锥、组合正轴棱锥、螺旋轴棱锥,并利用衍射理论分析了它们的光传输特性,还研究了无衍射光束经环形障碍物的重建和高阶贝塞尔-高斯光束的聚焦重建特性,研究内容主要包括如下:1.提出一种可产生无衍射Bessel光的新型光学元件──组合锥透镜,由正、负轴棱锥胶合在一起设计而成。其变换光束特性与单个正轴棱锥相同,等效底角由正、负轴棱锥底角之差决定,因此可通过较大底角的正、负轴棱锥组合得到更小角度的底角,以获得更长距离的无衍射光,数值模拟平面波通过组合锥透镜后的光场为无衍射Bessel光,并从几何光学角度用Zemax软件模拟组合锥透镜后的光场分布,研究结果为获得长距离无衍射Bessel光开辟一条新的途径。2.设计了可产生局域空心光束的阶变折射率轴棱锥和组合正轴棱锥,具有结构简单,容易加工等优点,利用衍射积分理论数值模拟两种新型光学元件光传输的光场分布和不同距离处的二维光斑图,在原子引导和囚禁、光学捕捉及光镊等方面有广泛的应用。3.利用Hankel波理论和几何光学原理对无衍射光经环形障碍物的重建过程进行分析,并用Zemax软件对无衍射光经环形障碍物进行光线仿真,模拟了环形障碍物后的轴上不同位置处的截面光强图,设计实验,实验和仿真结果基本吻合。理论和实验结果均表明无衍射光束经环形障碍物后会重建并能产生中心光强为零的局域空心光束。4.提出利用薄透镜元件对聚焦后的高阶贝塞尔-高斯光束进行重建。基于衍射理论分析其聚焦后的重建行为,数值模拟高阶贝塞尔-高斯光束经薄透镜聚焦再通过另一薄透镜重建的三维光场分布和截面光强分布图,结果表明高阶贝塞尔-高斯光束经单个薄透镜后产生中空的局域空心光束,在焦点后合适位置处放入另一薄透镜可矫正焦点后发散的光束,使得其后光场不变,仍满足贝塞尔分布。更多还原

【Abstract】 In this thesis, several new optical elements are designed, including novel axicon、Step refractive index axicon、combined positive axicons and helical axicon, and their optical propagation properties are analyzed, The reconstructions of Bessel beam with an annular obstacle and focused high order Bessel-Gauss beams are studied either, the main results are summarized as following:1. A new type of optical element --- combined axicon was proposed for generating non-diffracting Bessel beams, this element is designed with gluing positive and negative axicon. Its property is the same as single positive axicon for beam transformation, and equivalent cone angle is decided by the cone angle difference of positive and negative axicon, therefore, we can get smaller cone angle by combining positive and negative axicon with comparatively large cone angle for each axicons, also get longer non-diffracting distance. The numerical calculation results show that the combined axicon can transform plane wave to Bessel beam. The optical field distribution behind combined axicon was also simulated by Zemax software, Research results open a new way for generating non diffracting Bessel beams with a longer non-diffracting distance.2. Step refractive index axicon and combined positive axicons for generating Bottle beam is designed, they have advantages of simple structure and easy processing. The optical field distribution and 2D light spot image in different propagation distance behind two kinds of axicons are numerical simulated by the diffraction integral theory. Research results show the significant guidance for the practical applications of the bottle beam.3. Based on Hankel waves theory and geometric optical theory, the reconstruction of Bessel beam disturbed by an annular obstacle is studied, non-diffracting beam disturbed by annular obstacle is simulated with Zemax software, the cross sections intensity distribution at different place on axis behind annular obstacle is stimulated, the experiment is designed, and the result agrees with the simulation. The theoretical analysis and experimental results both show that reconstruction of Bessel beam with an annular obstacle can generate Bottlte beam with zero central optical intensity.4. Reconstruction of focused high order Bessel-Gauss beams by using thin lens is proposed. Based on the diffraction theory, reconstruction behavior of focused high order Bessel-Gauss beams is analyzed. The three dimensional optical intensity distribution and the cross section optical intensity distribution of the high order Bessel-Gauss beam focused by first thin lens, and then reconstructed by the second thin lens are numerical simulated. Result shows that the high order Bessel-Gauss beams pass through the single thin lens can generate Bottle beam. To rectify the beam divergence after focus, another thin lens is introduced at suitable position. After that, the beam keeps the Bessel distribution.更多还原