Patent ID: 8254223

Claim:
An optical drive device for performing information recording or reproduction of recorded information by formation of a mark by focusing a first light at a necessary position in a recording layer of an optical recording medium by an objective lens, the optical drive device comprising: a position control unit configured to focus a second light on a reflection film, in which a position guide element of the optical recording medium is formed, through the objective lens and to enable a spot position of the second light to follow the position guide element based on a reflected light of the second light focused on the reflection film so as to control a position of the objective lens; a first focusing unit configured to focus the reflected light from the optical recording medium of the second light incident through the objective lens by irradiating the second light to the optical recording medium; a first light-sensing portion disposed such that a spot of the reflected light from a surface of the optical recording medium included in the reflected light of the second light focused by the first focusing unit is formed on a light-sensing surface thereof; and a surface reflection light deviation amount detection unit configured to detect a deviation amount from a reference position in the light-sensing surface of the spot of the reflected light from the light-sensing surface, based on a light-sensing signal by the first light-sensing portion; the spectroscopic element includes a first hologram element and spectrally splits the reflected light of the second light incident through the objective lens by diffraction, the first focusing unit is disposed at a position where both a 0-order light and a 1-order light spectrally split by the spectroscopic element as the first hologram element are focused; and the first light-sensing portion is disposed at a position where the spot by the first focusing unit of the reflected light from the surface included in the 1-order light side output from the spectroscopic element is formed on the light-sensing surface.