Extended depth of focus in a particle field measurement using a single-shot digital hologram

Abstract

We propose a method to extend the depth of focus in a particle field measurement using a single-shot digital hologram. A focal plane is obtained for each pixel based on an entropy method, and a depth map is subsequently extracted. A synthesized extended focused image is determined correspondingly using the extracted depth map. In addition, a wavelet modulus maxima algorithm and Canny algorithm are further employed to detect the edges of each particle, and the sizes and a three-dimensional localization of the particles are also estimated. Preliminary results are presented to show the feasibility and effectiveness of the proposed technique. © 2009 American Institute of Physics.