The present invention relates to a method of manufacturing liquid crystal devices.
Liquid crystal displays have been broadly applied to personal computors, wordprocessors, and others. Liquid crystals mainly used in such devices are twisted nematic type materials. On the other hands, liquid crystal materials exhibiting smectic A and chiral smectic C phases are attracting interest of researchers because of new type driving modes.
In case of smectic phases, it is likely that external force or impacts likely cause disturbance in molecular arrangement of the liquid crystal. Unevenness of the cell thickness produces color shade in the display driven in accordance with the birefringence mode. The provision of spacers are used for fixing a pair of substrates at intermediate positions in order to deal with the problems.
The distance between a pair of substrates have to be so chosen as to unwind molecular spirals formed in the chiral smectic C liquid crystal layer disposed between the substrates. In order to dispose a liquid crystal material, the mated substrates are placed in a vacuum chamber and the pressure is reduced so that the air present in the inner space between the substrates is evacuated therefrom. Then, after an amount of the liquid crystal material is poured to an inlet port provided at a prepheral position of the mated pair of substrates, the pressure in the vacuum chamber is elevated in order to introduce the liquid crystal material into the inner space at an elevated temperature at which the phase of liquid crystal material exhibits a low coefficient of viscosity. Finally, the inlet port is closed by a suitable sealing material.
However, in accordance with this conventional method, void spaces may be produced in the liquid crystal layer due to thermal contraction and therefore the yield of product is substantially reduced.
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