Effect of Wavefront Properties on Numerical Aperture of Fresnel Hologram in Incoherent Holographic Microscopy
WAN Yu-Hong1,2**, MAN Tian-Long1,2, CHEN Hao1,2, JIANG Zhu-Qing1,2, WANG Da-Yong1,2
1Institute of Information Photonics Technology, Beijing University of Technology, Beijing 100124 2College of Applied Sciences, Beijing University of Technology, Beijing 100124
Abstract：Fresnel incoherent correlation holographic (FINCH) microscopy is a recently developed new technique, which employs a spatial light modulator (SLM) as the beam splitter. Light originating from the same object point is split into two beams by the wavefront-division phase mask displayed on SLM, and a Fresnel-zone plate-like hologram is formed by the interference of the two beams. The numerical aperture NAH of the recorded Fresnel hologram is introduced as a comprehensive parameter for evaluating the imaging characteristics in the FINCH scheme. The effect of wavefront properties on NAH of the hologram is investigated theoretically in the sense of optimizing imaging resolution. The variation trends of NAH are described and an optimal NAH is achieved by implementing an appropriate phase mask for a given recording distance between SLM and CCD; thus optimized imaging resolution and signal-to-noise ratio are demonstrated experimentally.
2014, Vol. 31 
