OPTICAL ELEMENT, COLLECTING BACKLIGHT SYSTEM, AND LIQUID CRYSTAL DISPLAY DEVICE

摘要

PROBLEM TO BE SOLVED: To provide an optical element which can collect and make parallel incident light from a light source by utilizing two or more circular polarization type reflective polarizers and which can reduce the coloring of the light which are made incident on the element at larger angles with respect to the direction of a normal line.

SOLUTION: This element is an optical element in which at least the two or more circular polarization type reflective polarizers (a) in which selective reflection wavelength bands of the polarization are overlapped mutually are laminated and the optical element is characterized in that at least the two circular polarization type reflective polarizers are arranged so that sides of the polarizers which selectively reflect shorter wavelengths of the selective reflection wavelength bands in the polarizers (a) are opposed to each other.

COPYRIGHT: (C)2005,JPO&NCIPI