COMA ABERRATION CORRECTION DEVICE, COMA ABERRATION PROFILE CALCULATION METHOD, AND COMA ABERRATION CORRECTION METHOD

摘要

This coma aberration correction device is equipped with: a first coma aberration profile calculation means that emits a second light beam (L1) to a guide layer (51) at multiple positions in order to calculate a coma aberration profile of the guide layer; a coma aberration calculation means that emits the second light beam to one recording layer (L0) at a predetermined radial position (R1) in order to calculate a coma aberration at the predetermined radial position; a second coma aberration profile calculation means that calculates a coma aberration profile at the predetermined radial position by using the coma aberration at the predetermined radius value position of the one recording layer, the coma aberration profile of the guide layer, and positional information on the respective layers in the thickness direction; a third coma aberration profile calculation means that calculates coma aberration profiles of multiple recording layers by using the coma aberration profile of the guide layer and the coma aberration profile at the predetermined radius position; and a correction means that applies a control voltage, which is based on the coma aberration profiles of the multiple recording layers, to a correction component (LC1) in order to correct the coma aberration of the second light beam.