| 摘要 |
PURPOSE: To make it possible to control colorless display and color display by specifying the product of the refractive index anisotropy of liquid crystals and the thickness of a liquid crystal layer, the refractive index in the inward direction of a double refractive plate and the refractive index in its thickness direction and the total sum of the refractive index anisotropy of a delay phase axis and advance phase axis and the double refraction in the perpendicular direction by the thickness to specific values. CONSTITUTION: The product Δn1 .d1 of the refractive index anisotropy Δn1 of the liquid crystals and the thickness d1 of the liquid crystal layer is specified to 1.2 to 2.5μm and the liquid crystal display device is provided with the double refractive plate in such a manner that nx >=nz >=ny is attained when nx , ny are defined as the refractive indices in the inward direction of the double refractive plate and (nx >ny ) and nz is defined as the refractive index in the thickness (d2 ) direction of the double refractive plate. The sum total Δn2 .d2 of the refractive index anisotropy of the phase delay axis and the phase advance phase and the double refraction in the perpendicular direction by the thickness is specified to 1.2 to 2.5μm and voltage values of >=3 values are impressed. The values of Δn1 .d1 and twist angle of the liquid crystal layer, Δn.d2 of the double refractive plate and N2 are optimized when the direction of the delay phase axis 9 of the double refractive plate 4 in the major axis direction of liquid crystal molecules 7 is defined as θ2 and the direction of the absorption axis 6 of the liquid crystal molecules 8 as θ3. Nz =(nx -nz )/(nx -ny ) is set. |
