Patent ID: 7365296

Claim:
A light reception output controlling apparatus of a photo detector in an optical pickup unit, the optical pickup unit configured to guide a laser beam emitted from a laser source to an objective lens, to converge the laser beam with the objective lens to be irradiated to a disk, and to guide the laser beam reflected and returned by the disk to the photo detector including a light reception region constituted by a plurality of segments, the light reception output controlling apparatus comprising: an amplifier provided in the photo detector corresponding to each of the segments of the light reception region; an output terminal provided in the photo detector, the output terminal outputting a light reception output corresponding to each of the segments via each of the amplifiers; and an output setting circuit that sets each light reception output from each of the output terminals by changing a gain of each of the amplifiers and/or by attenuating an input or output of each of the amplifiers with an attenuator, wherein each light reception output from each of the output terminals is corrected with the output setting circuit depending on an output difference generated in each light reception output from each of the output terminals based on a position of a light reception spot projected on the light reception region.