POLARIZED LIGHT SEPARATOR, POLARIZED LIGHT CONVERSION ELEMENT AND LIQUID CRYSTAL DISPLAY DEVICE FORMED BY USING THE SAME

摘要

PROBLEM TO BE SOLVED: To efficiently obtain a polarized light conversion element which is wide in an incident angle margin and is light in weight by holding a uniaxial anisotropic transparent medium which is arranged with a major axis direction nearly perpendicularly to incident light or the incident surface of the incident light at the boundary with isotropic transparent media between these isotropic transparent media. SOLUTION: The uniaxial anisotropic transparent medium 20 having refractive index anisotropy Δn is arranged between the isotropic transparent media 11 and 12 in such a manner that its major axis direction is made perpendicular to the plane of this paper. The refractive index np of the isotropic transparent media 11, 12 and the refractive index ne in the major axis direction of the uniaxial anisotropic transparent medium 20 are selected equal and the angle α of inclination is so set as to satisfy np.sinα>=(ne-Δn). At this time, the P polarized light transmits the boundary between the isotropic transparent medium 12 and the uniaxial anisotropic transparent medium 20 as it is to form exit light 61. The S polarizing plate reflects totally at the boundary to form reflected light 62. Further, if a halfwave plate 30 is arranged to incline 45 deg. with the S polarizing plate, the transmitted light 64 rotated 90 deg. in the direction of polarization is obtd. The conversion of all of the polarizing plate to the same linearly polarized light is thus made possible.