An optical head device 201 includes a light source 1, an objective lens group 13, a two-dimensional actuator 15, spherical aberration adding means 9, 10, and 16, a hologram element 17 for splitting the light beam from the optical disk 14 into a plurality of split light beams, and a photodetector 22 which includes at least one photoreceptor including a plurality of split light receiving areas and outputs an electric signal corresponding to the light amount of a split light beam entering each of the plurality of split light receiving areas or an electric signal corresponding to a combination of the light amount of split light beams entering the corresponding split light receiving areas, and the plurality of split light beams split by the hologram element 17 include one circular ray U1 and at least two annular rays U2 and U3.

 
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