Patent ID: 7682676
Filing Date: 2010-03-23
Classification: G02B,Y10T

Abstract:
1. An optical pickup apparatus, comprising: a light source to emit a laser light flux having a wavelength of 350 nm to 450 nm; and an optical element arranged at a position where the laser light flux having a wavelength of 350 nm to 450 nm passes through the optical element; wherein the optical pickup apparatus conducts recording and/or reproducing information by converging the laser light flux having passed through the optical element onto a information recording plane of an optical information recording medium, wherein the optical element comprises: a synthetic resin base member; and an antireflection film provided on the synthetic resin base member and including a contact layer being in contact with the synthetic resin base member, wherein the contact layer is a film made of a material containing no oxygen atom or a film made of a mixed material of a material containing no oxygen atom and a material containing an oxygen atom in which the mixed material contains the material containing an oxygen less than 10%, wherein the synthetic resin base member is a base member made of a resin containing a polymer including an alicyclic hydrocarbon group.