APPARATUS FOR DETECTING TILT

摘要

PURPOSE: An apparatus for detecting a tilt is provided to detect easily a tilt between a recording surface of an optical disc and an axis of a beam irradiated on the recording surface by improving a structure of a tilt detection device. CONSTITUTION: An optical disc(1) is loaded on a tilt detection device. A track(1a) is formed on a recording surface of the optical disc(1). The optical disc(1) is composed of a land and a groove. An optical pickup portion(2) reads information recorded on the track(1a) and detects a tilt between the recording surface of the optical disc(1) and an optical axis of an incident beam. An operation portion(3) receives a radiation intensity signal output from the optical pickup portion(2) and outputs a tilt signal by performing a predetermined operation. An optical irradiation portion(4) is formed with a laser diode in order to generate a beam. A collimate lens(5) is used for converting the beam to a parallel beam. A beam splitter(6) is used for reflecting the parallel beam and refracting an axis of the beam as much as 90 degrees. An objective lens(7) projects the reflected beam to the track(1a) of the optical disc(1). A light receiving lens(8) receives the reflected beam. A light receiving portion(9) is formed by a photo diode.