OPTICAL INTEGRATION UNIT PROVIDED WITH HOLOGRAM ELEMENT AND OPTICAL PICKUP DEVICE

摘要

An optical integration unit (40) comprising a light emitting unit (1) for oscillating a plurality of laser beams with different wavelengths, a wavelength plate (5), a polarization hologram element (2) for diffracting a first laser beam oscillated from a light source (1a), and a non-polarizing hologram element (3) for diffracting a second laser beam oscillated from a light source (1b). The wavelength plate (5) is formed so as to act as a lambda/4 plate on the first laser beam and as a lambda plate or a lambda/2 plate on the second laser beam.