Optical pickup which is compatible with multiple types of media

摘要

An optical pickup which is compatible with different types of media is disclosed. A plurality of light sources (110,120,130) emit light with different wavelengths. Light path changers (140,150,160) change the path of light emitted by the plurality of light sources (110,120,130) so that the light is incident upon an objective lens (200). The objective lens (200) focuses the incident light onto a recording medium (D). A collimating lens (170) is disposed in front of the objective lens (200) to collimate the incident lights. The collimating lens (170) is movable to correct a spherical aberration. A diffractive optical element (180) is disposed in a path of a light with a short wavelength and has a diffractive surface to correct a chromatic aberration.