Patent ID: 8077320

Claim:
A wavefront measuring method comprising: a first obtaining step for obtaining a first two-dimensional phase image or a first transmitted wavefront based on a transmitted light beam when a light beam is made incident into an inspected substance at a first angle; a second obtaining step for obtaining a second interference fringe image formed based on a transmitted light beam when a light beam is made incident into the inspected substance at a second angle different from the first angle; a mask generating step for generating a mask corresponding to an interference degree of the second interference fringe image; a converting step for converting the first two-dimensional phase image to match with a temporary second two-dimensional phase image obtained based on the second interference fringe image or converting the first transmitted wavefront to match with a temporary second transmitted wavefront obtained based on the second interference fringe image; and an unwrapping step for unwrapping based on (1) the second interference fringe image, the mask, and the first two-dimensional phase image converted in the converting step, or (2) the second interference fringe image, the mask, and the first transmitted wavefront converted in the converting step, to obtain a second transmitted wavefront by a light beam transmitted through the inspected substance when a light beam is made incident into the inspected substance at the second angle.