Patent ID: 6246495
Filing Date: 2001-06-12
Classification: G03H

Abstract:
A phase-shift digital holographic apparatus comprising:a single wavelength light source for using as a reference wave and for generating an object wave emitting from an object;a phase shifting means for shifting a phase of the reference wave;a holographic image pickup means for producing holographic image data, having an image forming surface on which an object wave and the reference wave fall simultaneously, said object wave emitted from the object falling directly on the image forming surface without passing through a lens;an object wave calculating means for processing a plurality of holographic image data produced by the object wave and a plurality of reference waves of different phases determined by shifting the phase of the reference wave by the phase shifting means to calculate phase data on the phase of the object wave and amplitude data on the amplitude of the object wave; anda reproduced image calculating means for constituting object wave data of the phase data on the phase of the object wave and the amplitude data on the amplitude of the object wave calculated by the object wave calculating means, and subjecting the constituted object wave data to a two dimensional Fresnel transformation process to calculate a reproduced image, wherein the two dimensional Fresnel transformation process is done so that the reproduced image is represented by a two dimensional coordinate plane and a Z-coordinate value, wherein the two dimensional coordinate plane is set parallel to the image forming surface and the Z-coordinate value can be set so as to be related to a distance from the image forming surface to a position on the object in a direction perpendicular to the two dimensional coordinate plane, and wherein when the Z-coordinate value is set to said distance, the reproduced image represents a two dimensional image of the object at said position on the object.