An optical pickup device for reading data signals recorded in an optical recording medium such as a magnetooptical disk. A light beam emitted from a source of light is split by a light-splitting element into two light beams which are linearly polarized to meet at right angles with each other and which propagate in different directions. Then, a converter element changes the phase between the oscillation components of each light beam with respect to two orthogonal axes in a plane perpendicular to the beam path. This enables two differently polarized beams to overlap on the recording medium. Thus, the effective area of irradiation is made smaller than the actual beam spot size to provide high resolution.