Method of driving a liquid crystal display device

A method of driving a liquid crystal display device that uses a chiral nematic liquid crystal medium wherein liquid crystal molecules interposed between two substrates have a predetermined angle of twist in an initial state and said chiral nematic liquid crystal medium has two metastable states differing from said initial states as relaxation states achieved after a voltage that brings about a Frederick's transition has been applied in said initial state, said method comprising the steps of:

• a) during a reset period, applying to said liquid crystal medium a reset voltage greater than or equal to a threshold value that brings about said Fredericks' transition;
• b) during a first selection period after said reset period, applying to said liquid crystal medium a selection voltage selected on the basis of a critical value which brings about one of said two metastable states;
• c) during a nonselection period following said first selection period, applying to said liquid crystal medium a nonselection voltage less than or equal to a threshold value which maintains said two metastable states;
• and
• d) during a delay period between said reset period and said first selection period, applying to said liquid crystal medium a delay voltage that is less than or equal to said critical value which brings about one of said two metastable states.