OPTICAL INFORMATION RECORDING/REPRODUCING DEVICE, OPTICAL UNIT, AND OPTICAL INFORMATION RECORDING METHOD

摘要

An optical unit is provided with a light source, a light dividing means for dividing a light beam emitted from the light source into a first light beam and a second light beam, a light concentrating means for causing the first light beam and the second light beam to face each other in a recording layer and concentrating the light beams at the same position, a polarization state switching means capable of switching the polarization states at a concentration point of the first light beam and the second light beam in the recording layer, and a light irradiation state switching means capable of switching between the irradiation of an optical recording medium with both the first light beam and the second light beam and the irradiation thereof with either the first light beam or the second light beam.