液晶是１８８８年奥地利植物学家莱尼茨尔在合成胆醇脂时发现的：实验物质加热到１４５℃晶体开始熔解并逐渐变成乳白色粘稠状液体，温度达到１７８．５℃时粘稠状液体变清而成为各向同性的液体．该物质处于１４５－１７８．５℃之间的粘稠状态时具有双折射现象，这就是液晶． Liquid crystal was discovered in 1888 by the German botanist Lehnert in the synthesis of cholecalciferol: the test substance was heated to 145 ° C and the crystals started to melt and gradually became milky white viscous liquid. When the temperature reached 178.5 ° C, Liquid becomes clear and becomes isotropic liquid. The material has a birefringence in the viscous state between 145-178.5 ° C, which is the liquid crystal.