| 摘要 |
PROBLEM TO BE SOLVED: To effectively improve the problem of coloring by controlling the ratio of the change in the refractive index anisotropy of a liquid crystal material in a liquid crystal layer with wavelengths of light to the change in the refractive index anisotropy of an optical phase difference plate to such a range that no coloring is produced in a liquid crystal screen depending on the viewing angle. SOLUTION: Optical phase plates 2, 3 have principal refractive indices na , nb , nc in different three directions satisfying na =nc >nb . Since only one optical axis is present, the phase difference plates 2, 3 are uniaxial and show negative refractive index anisotropy. The ratio of the change in the refractive index anisotropy of the liquid crystal material in the liquid crystal layer 8 with wavelengths of light to the change in the refractive index anisotropy of optical phase difference plates 2, 3 with wavelengths of light is controlled to such a range that coloring of the liquid crystal screen depending on the viewing angle is not caused. Therefore, in a divided state of the liquid crystal layer 8, the compensation function of phase differences by optical phase difference plates 2, 3 can be combined with the best characteristics. |
