Parallel quasi-phase-shifting digital holography

We propose parallel quasi-phase-shifting digital holography as a technique capable of noiseless instantaneous measurement of three-dimensional objects. The technique implements four kinds of phase shifting at a time using a phase shifting array device located in the reference beam. The device is an array of 2x2 phase retarders. We conduct both numerical simulation and preliminary experiment, and the results agree well with those of the conventional phase shifting method. Also, the results are superior to those using a Fresnel transform alone, which is another digital holography method that can achieve instantaneous measurement. (C) 2004 American Institute of Physics.