| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an optical information recording reproducer for performing tilt adjustment and tilt correction of an objective lens that are applicable to a multi-layer BD having plural information recording surfaces. <P>SOLUTION: When coma aberration occurring by tilting an information recording medium to a unit angle is represented as SCD and coma aberration occurring by tilting an objective lens to the unit angle is represented as SCO, a relationship between the thickness of a cover layer of an information recording surface and a ratio α of the SCO to the SCD is previously obtained and recorded in recording means. When the ratio α of the information recording surface having the thinnest cover layer is represented as α1, a tilting range θ1 of the objective lens is determined on the basis of the α1, and the tilt adjustment of the objective lens is performed. When the ratio α of the target information recording surface is represented as α2, a tilting range θ2 of the objective lens is estimated on the basis of a ratio of the α2 to the α1, and the tilt correction of the objective lens is performed. <P>COPYRIGHT: (C)2012,JPO&INPIT |
