Patent ID: 8085626
Filing Date: 2011-12-27
Classification: G11B

Abstract:
1. An optical pickup device comprising: a first mirror for reflecting a first light beam outputted from a first light source and letting a second light beam outputted from a second light source pass therethrough; a first object lens for converging the first light beam reflected by the first mirror on an information recording surface of a recording medium; a second mirror for reflecting the second light beam passing through the first mirror; a second object lens for converging the second light beam reflected by the second mirror on the information recording surface of the recording medium; and an achromatic lens for correcting an axial chromatic aberration of the second object lens generated by wavelength variation of the second light beam, wherein the achromatic lens is provided in an optical path between the first mirror and the second mirror, wherein the achromatic lens comprises a diffractive surface and a concave surface, wherein the concave surface is disposed on a first-mirror side.