| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a polarization conversion element capable of readily preventing the light of a low polarization degree mingled with unnecessary light from being formed, and a lighting device, and a projector using the same. <P>SOLUTION: A second prism 83 is provided with a scattering side face 83c which is a light diffusion surface formed like ground glass and therefore even if unintended random polarized light L1 enters the scattering side face 83c, the degradation of the polarization degree of linearly polarized light LO can be prevented. Namely, even if the random polarized light L1 enters the scattering side face 83c, the random polarized light L1 is diffused and is hardly made incident on a polarizer separating film 84 and therefore the polarized light is prevented from leaking out of both exit faces 82d, 83d and eventually high polarization conversion efficiency can be achieved. If the front face of the scattering side face 83c is coated with Japanese ink, the direct incidence of the diffused light or scattered light on the polarizer separating film 84 can be prevented and the higher polarization conversion efficiency can be achieved. <P>COPYRIGHT: (C)2006,JPO&NCIPI</p> |
