WAVEFRONT MEASUREMENT DEVICE, WAVEFRONT MEASUREMENT METHOD, METHOD OF MANUFACTURING OPTICAL ELEMENT, AND METHOD OF MANUFACTURING OPTICAL SYSTEM

摘要

PROBLEM TO BE SOLVED: To measure the wavefront of an optical element and an optical system over a wide measurement range with high accuracy.;SOLUTION: Light from a light source 10 is divided into detected light and reference light, the detected light enters a detected object 50, the detected light passing through the detected object 50 or the detected light reflected on the detected object 50 enters a light flux dividing element 60 to be divided into plural pieces of detected light, the plural pieces of detected light enters a first surface 70a of a diffraction element 70, the plural pieces of detected light emitted from a second surface 70b of the diffraction element 70 and the reference light interfere with one another, to thereby measure interference light. A phase of the interference light is calculated, a centre of gravity position of the plural pieces of detected light is calculated, and the centre of gravity position and the phase of the interference light are used to calculate a wavefront of the detected object 50.;SELECTED DRAWING: Figure 1;COPYRIGHT: (C)2018,JPO&INPIT