Format

Send to

Choose Destination
See comment in PubMed Commons below
Opt Lett. 2008 Sep 1;33(17):1945-7.

Laplacian differential reconstruction of in-line holograms recorded at two different distances.

Author information

  • 1Department of Physics, Shandong Normal University, Jinan, China. guochsh@sdnu.edu.cn

Abstract

We analyze the diffraction of the picture obtained by the subtraction of two in-line holograms recorded in two planes at distances of z and z+Deltaz apart from the object plane. Our theoretical analysis reveals that the reconstructed field at the object plane is approximately equal to the Laplacian second-order differentiation of the object wave in transverse direction when Deltaz is much smaller than the distance z, that is, the reconstructed image presents a high quality of edge enhancement. We further investigate the dependence of the edge-enhancement quality on the longitudinal differential distance Deltaz and find that the reconstructed images have the sharpest edge-enhancement and high signal-to-noise ratio at the same time only when the value of Deltaz/z lies between 0.7% and 0.9% under our experimental condition. We also construct a criteria function, named the entropy of the image, to automatically focus the edge-enhanced image and demonstrate its adaptability in experiments.

PMID:
18758573
[PubMed]
PubMed Commons home

PubMed Commons

0 comments
How to join PubMed Commons

    Supplemental Content

    Full text links

    Icon for Optical Society of America
    Loading ...
    Support Center