POLARIZATION SURFACE ROTATING OPTICAL DEVICE, POLARIZATION TRANSFORMATION OPTICAL DEVICE, AND PROJECTION TYPE DISPLAY DEVICE

摘要

PURPOSE:To provide a polarization transformation optical device which transforms natural light efficiently into light near linear polarization. CONSTITUTION:A polarization transformation optical device is structured with a polarization beam splitter 141 and polarization surface rotating optical devices 142 and 143. In the polarization surface rotating device 142, one surface 155 and 156 of transparent plates are flat and minute prisms 157 and 158 are arranged on the other surface. A P polarization component emitted from the polarization beam splitter 141 is moved straight forward, and an S-polarization component is incident on the flat surfaces 155 and 156 of the polarization surface rotating optical device 142. The polarization surface rotating optical devices 142 and 143 rotate the polarization surface of an incidence linear polarization by 90 deg. by two times of reflections on the prisms 157 and 158, and bend the beam advancing direction by 90 deg.. Then, for its emitted light and P-polarization component moved straight forward from the polarization beam splitter 141, the polarization surface is aligned with the beam advancing direction. Thus natural light is transformed efficiently into light near linear polarization.