Patent ID: 6043940
Filing Date: 2000-03-28
Classification: G02B,G11B

Abstract:
An optical system for optical recording having a condenser lens for irradiating a laser beam on an optical recording medium, said condenser lens comprising a single crystal of any one of the group consisting of LiNbO3, LiTaO3, rutile phase TiO2, PbMoO4, TeO2, SrTiO3, ZrO2, SrNbO3, SrTaO3, CaNbO3, CaTaO3, CaTiO3, KNbO3, KTaO3, K(Ta, Nb)O3, BaZrO3, SrZrO3, CaZrO3, ZnWO4, ZnMoO4, CdWO4, CdMoO4, PbWO4, Bi20SiO12, Bi20GeO12, Bi4 Si3 O12, Bi4Ge3O12, GaP, ZnTe, ZnSe, Cu3TaSe4 and ZnS.