基于涡旋光照明的暗场数字全息显微方法研究

提出了一种基于涡旋光照明的暗场数字全息显微方法. 从理论上阐述了涡旋光环形照明原理和暗场数字全息显微原理, 分析了涡旋光的准无衍射特性对成像的影响; 搭建了相应的数字全息显微成像系统, 采用690 nm的聚苯乙烯小球作为实验样品; 最后通过对小球明暗场下数字全息显微再现像的分析对比, 证明该方法可以有效地提高数字全息系统的分辨率, 同时增强了再现像的对比度. 关键词： 全息 暗场数字全息显微 涡旋光 分辨率

Dark-field digital holographic microscopy by using vortex beam illumination

We propose a dark-field digital holographic microscopy (DHM) by using vortex beam illumination. In this paper, the annular illumination of vortex beam and the dark-field DHM imaging system are theoretically analyzed, and the quasi-nondiffracting property of the vortex beam is discussed. A corresponding DHM imaging system is established. The polystyrene spheres each with a size of 690 nm are utilized as objects in the experiment. By comparing the results of reconstructed images under bright-field illumination with those under dark-field illumination DHM, it is proved that the resolution of dark-field DHM under speckle-field illumination is improved and the contrast of its reconstructed image is enhanced accordingly.
Keywords： holography dark-field digital holographic microscopy vortex beam resolution