Transmitted wavefront measuring method, refractive-index distribution measuring method, method of manufacturing optical element, and transmitted wavefront measuring apparatus

摘要

A transmitted wavefront measuring method comprises the steps of emitting light (101) from a light source (100) onto an object to be measured (120) to receive interfering light transmitted through the object and a diffraction grating (130) on a light receiving portion (140) disposed at a predetermined distance from the diffraction grating to measure an intensity distribution of the interfering light (T10), performing a Fourier transform of the intensity distribution to calculate a frequency distribution (T20), and obtaining a transmitted wavefront of the object based on a primary frequency spectrum in the frequency distribution (T30 to T90). The step of obtaining the transmitted wavefront comprises the steps of performing an inverse Fourier transform of the primary frequency spectrum with reference to a grating frequency of the diffraction grating to calculate a complex amplitude of the interfering light (T60), and obtaining the transmitted wavefront based on the complex amplitude (T90).