REPRODUCING METHOD FOR PHASE SHIFT DIGITAL HOLOGRAPHY USING SPHERICAL WAVE REFERENCE BEAM, AND DISPLACEMENT DISTRIBUTION MEASURING METHOD AND DEVICE

摘要

PROBLEM TO BE SOLVED: To provide a reproducing method for phase shift digital holography using a spherical wave reference beam, and a displacement distribution measuring method using the phase shift digital holography using the spherical wave reference beam. SOLUTION: Images of an object are respectively taken five times by a CCD camera while sequentially shifting a phase of the spherical wave reference beam for a predetermined amount before and after displacement of the object, and respective five interference fringes are recorded as digital holography. A constant velocity phase shift method is used on each set of five interference fringes obtained in such way to obtain complex amplitude distributions on a CCD face before and after the displacement. Complex amplitude distributions of an object face before and after the displacement are obtained by Fresnel conversion from the complex amplitude distributions on the CCD face before and after the displacement. A phase difference distribution is obtained from the complex amplitude distributions of the object face before and after the displacement. COPYRIGHT: (C)2007,JPO&INPIT