Increased depth of focus in random-phase-free holographic projection  

作　　者：Michal Makowski Tomoyoshi Shimobaba Tomoyoshi Ito 

机构地区：[1]Warsaw University of Technology, Faculty of Physics [2]Graduate School of Engineering, Chiba University

出　　处：《Chinese Optics Letters》2016年第12期55-59,共5页中国光学快报（英文版）

基　　金：funded by the Polish National Centre for Research and Development(No.LIDER/013/469/L-4/12/NCBR/2013);the Polish National Science Centre(No.2015/17/B/ST7/03754)

摘　　要：The recently proposed random-phase-free method enables holographic reconstructions with very low noise,which allows fine projections without time integration of sub-holograms. Here, we describe the additional advantage of this method, namely, the extended depth of sharp imaging. It can be attributed to a lower effective aperture of the hologram section forming a given image point at the projection screen. We experimentally compare the depth of focus and imaging resolution for various defocusing parameters in the cases of the random-phase method and the random-phase-free method. Moreover, we discuss the influence of the effective aperture in the presence of local obstacles in the hologram＇s plane.The recently proposed random-phase-free method enables holographic reconstructions with very low noise,which allows fine projections without time integration of sub-holograms. Here, we describe the additional advantage of this method, namely, the extended depth of sharp imaging. It can be attributed to a lower effective aperture of the hologram section forming a given image point at the projection screen. We experimentally compare the depth of focus and imaging resolution for various defocusing parameters in the cases of the random-phase method and the random-phase-free method. Moreover, we discuss the influence of the effective aperture in the presence of local obstacles in the hologram＇s plane.

关 键 词：projection holographic aperture obstacles pixel sharp camera attributed convergent shadow 

分 类 号：O438.1[机械工程—光学工程]