An optical pickup device is provided which includes a double-wavelength objective lens (34) that collects a light beam selectively emitted from a light-emitting/-detecting element (31) that selectively emits a plurality of light beams different in wavelength from each other, and also return light from an optical disk (2), a first diffraction grating (45) that splits the light beam emitted from a light-emitting/-detecting element (31) into three beams including a zero-order light beam and positive and negative first-order light beams, a second diffraction grating (46) that diffracts the return light for traveling along a light path separate from that of the outgoing light, and a third diffraction grating (47) that corrects a light-path deviation by diffracting the positive first-order light beam diffracted by the second diffraction grating (46). The light-emitting/-detecting element (31) provides a focusing error signal FE by detecting the negative first-order light beam diffracted by the third diffraction element (47), and a tracking error signal by detecting return portions of the positive and negative first-order light beams from the first diffraction grating (45).

 
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