OPTICAL PICKUP DEVICE AND METHOD FOR DETECTING TILTING QUANTITY

摘要

PURPOSE: To provide an optical pickup device which has the possibility of a wide range of application applicable to various devices and optical systems, also is capable of detecting a tilting quantity with high precision, has high performance and also is suitable for miniaturization. CONSTITUTION: The device is provided with a light receiving means which receives diffracted light reflected from a recording medium and a detecting means which detects the tilting quantity of the recording medium based on the intensity of light of an interference area between zero-order diffracted light and at least one diffracted light of diffracted light other than zero-order diffracted light of reflected light received by the light receiving means.