Ultra-resolving optical pickup device having an optical detector receiving an unfiltered reflected beam

An optical pickup device comprising:

• a laser source;
• an objective lens for converging a laser beam radiated from the laser source on an optical disk surface;
• light reducing means disposed between the laser source and the objective lens and receiving, as an input, the laser beam from the laser source, the light reducing means reducing light intensity of the received laser beam at around its cross sectional center so as to separate the received laser beam and to provide an output consisting of a single laser beam consisting of a main lobe and a pair of side lobes placed at both sides of the main lobe toward the objective lens, the light reducing means being positioned so that the objective lens converges the main lobe from the light reducing means on a track of the optical disk, the track being composed of a line of pits while converging the side lobes at positions oppositely shifted from a track center by a predetermined amount in a track pitch direction;
• a first optical detecting means, disposed at a converging point of a single laser beam reflected by the optical disk surface, for receiving the reflected single laser beam through the objective lens, the first optical detecting means receiving the main lobe in the reflected single laser beam so as to detect signals corresponding to information stored in the optical disk;
• and
• a second optical detecting means, disposed at a converging point of the reflected single laser beam, for receiving the reflected single laser beam through the objective lens, the second optical detecting means including a pair of detecting elements for receiving the side lobes in the reflected single laser beam so as to detect tracking error signals.