REFLECTION TYPE LIQUID CRYSTAL DISPLAY ELEMENT

摘要

PROBLEM TO BE SOLVED: To make it possible to obtain an excellent display grade by specifying a parameter so that the compatibility of brightness with a contrast is attained. SOLUTION: A supporting substrate 1a is provided with a reflection plate 2 in common use as display electrodes and an oriented film 4a of liquid crystal molecules. This transparent substrate 1b is provided thereon with transparent electrodes 3 and an oriented film 4b. A liquid crystal layer 5 into which dichromatic dye and chiral materials are incorporated is disposed between the oriented films 4a and 4b. The coefft. of light absorption to the linearly polarized light in a direction approximately parallel with the liquid crystal molecules is defined as k1 , the coefft. of light absorption to the linearly polarized light in the direction perpendicular thereto as k2 and the order parameter of the liquid crystal material contg. the dichromatic dye as S. The product Kmcd of KM expressed by KM=3k1 /(1+2S) or KM=3k2 /(1-S), the dye concn. c% and the thickness dμm of the liquid crystal layer 5 is so set as to satisfy 3S<2> -7.3S+5.7<=Kmcd <=14.7 S<2> -15.1S+6.15 within a range of 0 to 5V of the effective value of the voltage impressed on the liquid crystal layer 5.