Optical pickup apparatus and tilt amount detecting method

摘要

An optical pickup apparatus includes a photodetector (10) for receiving a diffracted light reflected from the recording medium; and a tilt detector (11) for detecting a tilt amount of the recording medium on the basis of a light intensity within an interference region of a 0th-order diffraction light and at least one diffraction light other than the 0th-order diffraction light of the reflected light received by the photodetector. <IMAGE>