OPTICAL SURFACE MEASURING METHOD AND APPARATUS USING DEFORMABLE MIRROR

摘要

The present invention relates to a method and a device to measure a shape of a non-spherical optical surface including a free-form surface, comprising: a collimation light source forming a light wave front without distortion; a beam splitter which partially reflects the light wave front created from the collimation light source while partially transmitting the same; a deformable mirror which deforms the light wave front reflected from the beam splitter in order to correspond to a shape of the measured optical surface; a lens which diverges the wave front if the shape of the measured optical surface is concave, and which converges the wave front if the shape of the measured optical surface is convex; a wave front sensor which receives an incidental wave front reflected from the measured optical surface to measure a remaining wave front error; and a control part connected to the deformable mirror which controls deformation of the reflecting face of the deformable mirror in order to correspond to the measured optical surface as measured in the optical surface, ultimately adding the remaining wave front error measured from the wave front sensor to the deformable information of deformable mirror, thus calculating the shape of the measured optical surface. The device is capable of performing real-time measurement, and is free from nuisance which stems from the fact that a new optical device should be manufactured every time a new non-spherical optical surface is being measured.