Provided is an optical pickup device capable to suppress an occurrence of
an aberration on a recording medium and a decrease of power of laser
beams while employing a diffraction grating as an optical axis correction
element.The laser element emitting the laser beam for CD (780 nm in
wavelength) is disposed between the laser element emitting the laser beam
for next-generation DVD (405 nm in wavelength) and the laser element
emitting the laser beam for DVD (650 nm in wavelength). Only the laser
beam for DVD is aligned by a diffraction effect of the optical axis
correction element (diffraction grating) with the optical axis of the
laser beam for next generation DVD. It is possible that a decrease of
laser power due to diffraction efficiency is suppressed as much as
possible because only the optical axis of the laser beam for DVD is
aligned with the optical axis of the laser beam for next-generation DVD.
Also it is possible that the optical axis of the laser beam for CD not
subjected to the optical axis correction is brought close to the optical
axis of laser beam for next-generation DVD considerably, thereby an
aberration occurring in the laser beam for CD can be suppressed at
minimum level.