The Research Of Particle Fields Reconstruction By Ditital Holography

Digital holography records holograms with solid-state imaging sensors (CCD), which integrates optical holography principle, computer technology, electronic technology and digital image resolution technology. With the digital holographic approach, holograms are directly recorded by a digital camera and reconstructed numerically. In this paper, digital holographic principle and its application in particle field reconstruction are studied specifically in both theory and experiment. The mathematical model of digital holographic record and reconstruction is made. According to the spherical wave and plane wave theories of light diffraction, two different digital reconstruction approaches are represented, i.e. frequent field reconstruction and Fresnel transform. The approach for utilizing digital holography combined with complex amplitude to reconstruct particle field distribution is studied and reconstructed numerically, which avoids not only traditional holographic physical and chemical processing, but also mechanical scanning of reconstructed 3D images. This paper designs a simple in-line holographic setup to reconstruct the particle fields, solving the low pixel resolutions of solid-state imaging sensors. The reconstructed particle's depth resolution is effectively modified by use of the complex amplitude. Complex amplitude information of reconstructed field is used fully, which enables the reconstructed particle accurately located. The correspondent programs are written with the MATLAB, by which the recorded digital holograms are processed analytically. Thus the particle field is clearly reconstructed, which proves the correctness of the theory.