Patent ID: 7289417

Claim:
An optical pickup comprising: a first objective lens to form an optical spot of a light beam used to record and/or reproduce data on a first recording medium; a second objective lens to form an optical spot of a light beam used to record and/or reproduce data on a second recording medium; a first light source emit a light beam having a wavelength suitable for the high-density recording medium; and at least one second light source to emit a light beam with a wavelength suitable for the low-density recording medium, wherein the first objective lens has a working distance WD 1 indicating a distance from the first objective lens to the high-density recording medium at a desired focus, the second objective lens has a working distance WD 2 indicating a distance from the second objective lens to the low-density recording medium at a desired focus which is longer than WD 1 , and the first and second obiective lenses are provided so that a distance D between the first objective lens and the high-density recording medium or the low-density recording medium satisfies the following expression: D=WD 1+α and α=| WD 2- WD 1|×(0.1-1.0), wherein at least one of the plurality of objective lenses is configured so that a type of wavefront error mainly generated by a tilt of the at least one of the plurality of objective lenses is the same as a type of a wavefront error mainly generated by an angle at which light is incident upon the at least one of the plurality of objective lenses.