An optical pickup apparatus for reproducing information from an optical information recording medium or for recording information onto an optical information recording medium, is provided with a first light source for emitting first light flux having a first wavelength; a second light source for emitting...http://www.google.ca/patents/US7173895?utm_source=gb-gplus-sharePatent US7173895 - Optical pickup apparatus, recording/reproducing apparatus provided with the optical pickup apparatus, optical element, and information recording/reproducing method
