Optical element and optical pickup apparatus

摘要

A production method of an objective lens for optical pickup apparatus having a numerical aperture NA of image side of 0.80 to 0.90 is disclosed. The method includes steps of molding resin composition containing copolymer of α-olefin and a cyclic olefin represented by Formula (I) or (II) to form lens shape, and thermally processing the molded product under a condition at a temperature between Tg −45° C. and Tg −15° C. for 12 to 168 hours, wherein the Formula (I) and (II) is detailed in the specification.