Patent ID: 8363977
Filing Date: 2013-01-29
Classification: G01B

Abstract:
1. A method of measuring an amount of deformation of a specimen employing a phase variation of an interference pattern caused by emitting light to the specimen, the method comprising: acquiring a first interference pattern image and two or more phase shift images having different amounts of phase shift for the first interference pattern image using an image pickup unit; acquiring a second interference pattern image after a lapse of a predetermined period of time using the image pickup unit; computing a phase of the first interference pattern image from the first interference pattern image and the two or more phase shift images; computing a first phase variation of an interference pattern image occurring during the predetermined period of time from the first interference pattern image, the phase shift images for the first interference pattern image, and the second interference pattern image using a calculation unit; computing a phase shift image for the second interference pattern image based on the phase of the first interference pattern image, the phase variation, and the amounts of phase shift; and computing the amount of deformation of the specimen based on the second interference pattern image and the two or more computed phase shift images for the second interference pattern image.