Patent ID: 6057817
Filing Date: 2000-05-02
Classification: G09G

Abstract:
A liquid crystal display using bistable nematic liquid crystal comprising:a liquid crystal cell having a pair of substrates having opposing electrodes and aligning films respectively formed on opposing inner surfaces of said pair of substrates, said aligning films having been subjected to an aligning treatment in a predetermined direction, and a liquid crystal layer of a bistable nematic liquid crystal material, sealed between said pair of substrates and having liquid crystal molecules selectively alignable in one of a first metastable aligned state and a second metastable aligned state different from each other by selective application of a twist select voltage having a plurality of different predetermined voltage values smaller than a voltage value of a reset voltage after application of said reset voltage, said voltage value of said reset voltage being such as to align said liquid crystal molecules substantially perpendicular to said substrates, a tilt angle of said liquid crystal molecules to said substrates being controlled in said first metastable aligned state and said second metastable aligned state in accordance with an effective value of a voltage to be applied to said opposing electrodes;at least one polarizing plate located on one outer side or both outer sides of said pair of substrates;a first driver for, in accordance with display data externally supplied, supplying a reset potential for applying said reset voltage between said electrodes, and a write-period voltage for designating a period for applying a voltage with an effective value according to said display data between said electrodes, both to one of said electrodes of said pair of substrates;a second driver for, in accordance with said display data, supplying a metastable-aligned-state selecting voltage for selectively applying a first metastable-aligned-state selecting voltage and a second metastable-aligned-state selecting voltage between said electrodes, and a write voltage for, in accordance with said display data, varying said effective value of said applied voltage during a period designated by said write-period voltage, both to the other electrode of said pair of substrates respectively in synchronism with said reset voltage and said write-period voltage; anda power source for supplying said reset voltage, said write-period voltage, said metastable-aligned-state selecting voltage and said write voltage to said first driver and said second driver.