An optical head includes a diffraction element capable of improving the quality of a TE signal by a DPP method even if light amounts of two sub-spots are unbalanced for optical discs having different groove pitches. In a three-beam optical head, a diffraction element is divided in a radial direction of an optical disc into a first area, a second area and a third area, wherein the second area is further divided into a fourth area and a fifth area. The periodic structure of the first area is displaced from that of the fourth area by a ¼ period, the periodic structure of the third area is displaced from that of the first area by a ½ period, and the periodic structure of the fifth area is displaced from that of the third area by a ¼ period and from that of the fourth area by a ½ period.