Patent ID: 6181309
Filing Date: 2001-01-30
Classification: G02F,G09G

Abstract:
A color liquid crystal display device, comprising:a nematic liquid crystal layer having a positive dielectric anisotropy and including a chiral material interposed between two substrates each having a transparent electrode and an alignment layer formed in substantially parallel;a twist angle of the liquid crystal layer, formed by the alignment layer is 160.degree.-300.degree.;a pair of polarizers disposed outside the liquid crystal layer;a birefringent plate disposed at at least one side of the liquid crystal layer; anda driving circuit configured to apply a driving voltage across the transparent electrodes,wherein:a product .DELTA.n.sub.1.multidot.d.sub.1 of a refractive index anisotropy of liquid crystal of the liquid crystal layer and a thickness d.sub.1 of the liquid crystal layer is 1.2-2.5 .mu.m;the birefringent plate has a slow axis and a fast axis;a sum of a product .DELTA.n.sub.2.multidot.d.sub.2 of the refractive index anisotropy of the slow axis and the fast axis and a thickness in a vertical direction is 1.2-2.5 .mu.m;when in a multiplex driving using a voltage averaging method, N represents a number of scanning electrodes, P.sub.N =N.sup.0.5 +1 and B.sub.R =(V.sub.r +V.sub.c)/(V.sub.c), a ratio (V.sub.r +V.sub.c)/(V.sub.c) of a magnitude (V.sub.r +V.sub.r) of a voltage in a selection time to a magnitude (V.sub.c) of a voltage in a non-selection time in a time that a pixel signal produced by a scanning signal and a data signal is in an ON display, B.sub.R.ltoreq.P.sub.N -2 is satisfied; anda voltage value of 3 or more is selected.