Object shape measuring method, object shape measuring apparatus, optical phase measuring method, and optical phase measuring apparatus

摘要

PROBLEM TO BE SOLVED: To provide an object shape measurement method that enables a measurement of a surface shape of an object possible to contain a height difference exceeding a wavelength of light to be used without conducting phase connections.SOLUTION: From first object light and first reference light of a first wavelength including information on a surface shape of an object, a first interference fringe and second interference fringe are actually created, and a third interference fringe and fourth interference fringe are virtually created, and then, intensity distributions of these four interference fringes are obtained. From the intensity distributions of the four interference fringes, a first phase distribution is calculated that is included in the first object light. From second object light and second reference light of a second wavelength including information on a surface shape of an object, a fifth interference fringe and sixth interference fringe are actually created, and a seventh interference fringe and eighth interference fringe are virtually created, and then, intensity distributions of these four interference fringes are obtained. From the intensity distributions of the four interference fringes, a second phase distribution is calculated that is included in the second object light. From the first phase distribution and second phase distribution, a depth distribution is calculated that represents the surface shape of the object .SELECTED DRAWING: Figure 1