Patent ID: 7397752

Claim:
A pickup for a magneto-optical recording medium for recording information into a magneto-optical recording medium and/or reproducing information from a magneto-optical recording medium, comprising: a light source for emitting light; an objective lens for collecting light emitted from the light source onto an information recording surface of a magneto-optical recording medium; a light-branching diffraction element provided between the light source and the objective lens for diffracting light reflected by the magneto-optical recording medium that has passed through the objective lens; first and second polarization/separation elements for polarizing and separating + first-order diffracted light and − first-order diffracted light that are diffracted through the light-branching diffraction element, respectively; first and second light detectors for receiving and detecting light separated by the first and second polarization/separation elements, respectively; a first phase compensation element provided on the optical passage of the + first-order diffracted light between the light-branching diffraction element and the first polarization/separation element; and a second phase compensation element provided on the optical passage of the − first-order diffracted light between the light-branching diffraction element and the second polarization/separation element, wherein an amount of phase compensation for the + first-order diffracted light of the first phase compensation element is different from an amount of phase compensation for the−first-order diffracted light of the second phase compensation element, according to two kinds of magneto-optical recording mediums which have different recording film structures.