OBJECTIVE LENS, OPTICAL PICKUP DEVICE, AND OPTICAL RECORDING/REPRODUCING APPARATUS

摘要

PURPOSE: An objective lens, an optical pickup device, and an optical recording/reproducing apparatus are provided to reduce the spherical aberration which is caused by an optical recording medium by preventing the curvature of the optical recording medium from being excessively increased. CONSTITUTION: An objective lens(8) is formed by a short lens. At least one surface of the objective lens is formed in an aspherical shape. The aspherical surface of the objective lens is rotationally symmetrical to correct the spherical aberration or the coma aberration. The objective lens performs the focusing and tracking to execute the recording/reproducing function normally. The objective lens has a light source side(8a) and an optical recording medium side(8b). The light source side and optical recording medium side are formed in a convex shape around the optical axis.