SURFACE SHAPE MEASUREMENT METHOD AND SURFACE SHAPE MEASUREMENT DEVICE AND OPTICAL ELEMENT USING SURFACE SHAPE MEASUREMENT METHOD AND SURFACE SHAPE MEASUREMENT DEVICE

摘要

PROBLEM TO BE SOLVED: To solve the problem in which in a method of projecting a light flux to a measured surface via an optical system and measuring a measured surface shape by detecting a wavefront of a reflection light flux, an error of the optical system makes a highly accurate measurement of the measured surface shape difficult.;SOLUTION: In a surface shape measurement method configured to: project light from a light source to a known reference surface via an optical system; measure, by a detection unit, a light lay angle distribution of a reflection light flux; similarly, measure a measured surface; and measure a measured surface shape from a difference between the measurement light ray angle distributions and a magnification distribution, the surface shape measurement method is configured to calibrate the magnification distribution on the basis of calculation of calculating a wavefront change before and after the reference surface is driven at a known amount, a result of measuring the wavefront change before and after the reference surface is driven by driving the reference surface at the known amount, and the magnification distribution.;SELECTED DRAWING: Figure 1;COPYRIGHT: (C)2016,JPO&INPIT