An optical disk apparatus includes a light source for emitting light in a prescribed wavelength range, an objective lens system for causing the light emitted from the light source to be focused onto a storage disk, and a reproduction signal system for causing return light from the storage disk to be...http://www.google.ca/patents/US20030223345?utm_source=gb-gplus-sharePatent US20030223345 - Optical disk apparatus with different transmission factors for polarized light
