#### Abstract

Four algorithms have been developed to reconstruct 3-D object points, all of which involve representation of the 3-D wavefront by its zero-crossings on the hologram plane. The first algorithm discussed is the Randomly Selected Zero-Crossing (RSZC) algorithm. This straightforward approach involves randomly selecting the positions of the desired number of apertures on the hologram plane, and perturbing each one of them until they satisfy the zero-crossing criterion. A second approach, the Fast Weighted Zero-Crossing algorithm (FWZC), is devised to combat some problems inherent with the RSZC algorithm. It can be considered to be the generalization of the zero-crossing techniques discussed above, with a fast architecture and removal of saturation through selective choice (i.e., thresholding) of zero-crossings. The final two algorithms, the Randomly Selected Zero-Crossing, Off Axis Plane Wave (RSZC-OPW) algorithm and the Fast Weighted Zero-Crossing, Off-Axis Plane Wave (FWZC-OPW) algorithm, are similar to the first two except that they are designed to be reconstructed with an off-axis (tilted) plane wave rather than a normally incident plane wave. This has potential advantages

#### Date of this Version

March 2006