Abstract: An optical pickup capable of compatibly adopting disks of different formats which are placed in an optical player includes a first optical source for emitting light having a predetermined wavelength, a second optical source for emitting light having a wavelength different from that of light emitted from the first optical source, an objective lens for focusing light emitted from the respective first and second optical sources on a recording medium placed in the optical player, a light path changing unit disposed on a light path between the first and second optical sources and the objective lens for changing the traveling path of incident light, a first optical detector for receiving light emitted from the first optical source and is incident via the recording medium and the light path changing unit, and a second optical detector for receiving light emitted from the second optical source and is incident via the recording medium and the light path changing unit.

Abstract: An optical pickup having a beam shaping device for changing an oval-shaped light beam emitted from a light source into a circular light beam, and an astigmatic difference correcting device for correcting the astigmatic difference of the light is provided. The beam shaping device is a cylindrical lens arranged between the light source and a beam splitter, having a convex cross-section, for converging the incident light, e.g., with respect to an X-axial direction. The astigmatic difference correcting device is an astigmatism lens arranged along an optical path between the cylindrical lens and a light path changing device, as a concave lens, for linearly passing light of a certain direction and diverging light of other directions.