| 摘要 |
PURPOSE:To obtain the light source unit which has light source brightness nearly twice as large as that when linear polarized light is obtained by merely using a polarizing plate by using a polarization beam splitter and a 1/2-lambda plate, and obtaining linear polarized light in the same direction from natural light and synthesizing it. CONSTITUTION:Light from the natural light 1a is passed through the polarization beam splitter 2 or reflected and polarized into linear polarized light beams 2a and 2b. The passing light passed through the polarization beam splitter 2 or reflected light is photodetected by the 1/2-lambda plate 3 and the angle of the polarization is varied by 90 deg.. The linear polarized light 3 which is changed in direction by 90 deg. and the passing light or reflected light from the polarization beam splitter 2 are superposed one over the other by a mirror 4 and those linear polarized light beams are polarized in the same direction. Consequently, the natural light is all polarized into the linear polarized light and the light source unit which has good efficiency is obtained. |
