To provide a color separating element having high spectroscopic characteristic.
A white parallel light beam transmitted from a surface light source device 3 is diffracted by a first diffraction grating 4 and, after transmitting through a prism array 12, diffracted again by a second diffraction grating 13. The color separating element is composed of the first and the second diffraction gratings 4, 13 and the prism array 12, the angles between the optical axes of red light R, green light G and blue light B, diffracted in the first order/ splitted by the first diffraction grating 4, are expanded wider by the prism array 12 and the second diffraction grating 13. Thus, the red light R, green light G and blue light B separated into large angles between optical axes are converged on the pixel 8 of a liquid crystal display panel 6 by a microlens array 5 and the light beam transmitted through the pixel 8 is diffused by a diffuser plate 7.
SHINOHARA MASAYUKI
AOYAMA SHIGERU
