Patent ID: 9594238
Date: 2017-03-14
CPC Classifications: G02B,G02F

Claim:
1. An aberration correction device for correcting wave front aberrations generated by an optical system including an objective lens disposed on an optical path of a light flux of coherent light to be emitted from a coherent light source, comprising: a symmetrical aberration correction element which corrects symmetrical aberrations among the wave front aberrations generated on the optical path, the symmetrical aberrations being wave front aberrations symmetrical with respect to an optical axis; an asymmetrical aberration correction element which corrects asymmetrical aberrations generated with respect to the light flux obliquely incident on the objective lens with a viewing angle at a periphery of an irradiation area of the coherent light, the asymmetrical aberrations being wave front aberrations asymmetrical with respect to the optical axis; and a control circuit configured to calculate a phase distribution pattern of the asymmetrical aberrations by adding the asymmetrical aberrations according to the viewing angle to residual aberrations of the symmetrical aberrations that remain after the correction of the symmetrical aberration by the symmetrical aberration correction element and depend on positional deviation due to oblique incidence of the light flux, obtain a phase modulation profile by inverting the phase distribution pattern, and make the asymmetrical aberration correction element display the phase modulation profile.