Optical integrated unit and an optical pickup apparatus using the same, an optical disk device

The present invention is, when using one beam tracking method reduction in light quantity is not in the main beam to suppress the occurrence of offset due to shift or a disk tilt of the objective lens, and to obtain a stable tracking servo performance. Between the hologram and the light receiving unit, further a diffraction grating arranged, changed into a diffraction efficiency grating longitudinal direction. For example, as an offset, the incident light on the diffraction grating is shifted in a lattice longitudinally causes a change in the amount of light received by each light receiving region. By performing the tracking servo so as to cancel the change, it is possible to correct the offset, it is possible to obtain a stable tracking servo performance.