An optical pickup head includes a light emitting and receiving unit (1), a
first lens (2), a second lens (3), and a beam splitter (4). The light
emitting and receiving unit (1) includes a semiconductor laser (10)
generating laser beams with different wavelengths which irradiate an
optical disk, and a photo detector (11) receiving laser beams reflected
by the optical disk. The first lens faces the light emitting and
receiving unit. The first lens includes an aspheric lens portion (20)
with a pair of opposite surfaces, and a diffraction grating (21) formed
on the surface of the aspheric lens portion which faces the light
emitting and receiving unit. The second lens is similar to the first
lens, and faces the optical disk for converging laser beams thereto. The
beam splitter is located between the first and second lenses.