| 摘要 |
PROBLEM TO BE SOLVED: To improve the contrast ratio by enabling achromatic white display with a single polarizing plate system capable of high resolution display, to enable low voltage drive so as to obtain easily visible display with excellent visibility and to achieve a full-color display. SOLUTION: Two optical phase difference compensation plates 8, 9 and one polarizing plate 10 are arranged in the light incident side of a TN liq. crystal cell 20 having positive dielectric anisotropy. The retardation of a liq. crystal layer 1, retardation in the substrate normal direction of the optical phase difference compensation plate 8, and retardation of the optical phase difference compensation plate 9 are brought into a range from 170 nm to 290 nm, from 80 nm to 150 nm, and from 200 nm to 360 nm, respectively. The angleαformed by the transmission axis or the absorption axis of the polarizing plate 10 and the lagging axis of the optical phase difference compensation plate 8 and the angleβformed by the transmission axis or the absorption axis of the polarizing plate 10 and the lagging axis of the optical phase difference compensation plate 9 satisfy a relation expressed by 35 deg.<=|2×β-α|<=55 deg.. The twist angle of the liq. crystal layer 1 is chosen to be in a range from 40 deg. to <90 deg.. The angleγformed by the lagging axis of the optical phase difference compensation plate 8 and the alignment direction of the liq. crystal molecules in the central part in the thickness direction of the liq. crystal layer 1 and the twist angleΔof the liq. crystal layer 1 satisfy a relation expressed by -Δ/2<=γ<=Δ/2.
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