Method for driving an antiferroelectric liquid crystal cell

Claim 1

A method for driving an antiferroelectric liquid crystal cell with an antiferroelectric liquid crystal or antiferroelectric liquid crystal composition held between a pair of substrates having electrodes, wherein when threshold voltages for the transitions from a third state to uniform states are V 1 and -V 1 and those for the transitions from the uniform states to the third state are V 2 and -V 2 , a voltage of at least V 1 or at most -V 1 is first applied to perform switching from the third state to a uniform state, a voltage Vk in the range of -V 2 <Vk<V 2 is applied during a memory time period for a uniform state→third state switching to retain said uniform state and subsequently, a driving voltage of at least V 1 or at most--V 1 is applied within said memory time period for the uniform state→third state switching to select one of the uniform states, after which the application of said voltage Vk and said driving voltage is repeatedly performed.

Claim 2

A method for driving an antiferroelectric liquid crystal cell with an antiferroelectric liquid crystal or antiferroelectric liquid crystal composition held between a pair of substrates having electrodes, wherein when threshold voltages for the transitions from a third state to uniform states are V 1 and -V 1 and those for the transitions from the uniform states to the third state are V 2 and -V 2 , a voltage of at least V 1 or at most -V 1 is first applied to perform switching from the third state to a uniform state, a voltage Vk in the range of -V 2 <Vk<V 2 is applied during a memory time period for a uniform state→third state switching to retain said uniform state and subsequently, a driving voltage of at least V 1 or at most--V 1 is applied within said memory time period for the uniform state→third state switching to select one of the uniform states, after which the application of said voltage Vk and said driving voltage is repeatedly performed.

Claim 5

A method for driving an antiferroelectric liquid crystal cell with an antiferroelectric liquid crystal or antiferroelectric liquid crystal composition held between a pair of substrates having electrodes, wherein when threshold voltages for the transitions from a third state to uniform states are V 1 and -V 1 and those for the transitions from the uniform states to the third state are V 2 and -V 2 , a voltage of at least V 1 or at most -V 1 is first applied to perform switching from the third state to a uniform state, a 0 voltage is applied during a memory time period for a uniform state→third state switching to retain said uniform state and subsequently, a driving voltage of at least V 1 or at most -V 1 is applied within said memory time period for the uniform state→third state switching to select one of the uniform states.

Claim 6

A method for driving an antiferroelectric liquid crystal cell with an antiferroelectric liquid crystal or antiferroelectric liquid crystal composition held between a pair of substrates having electrodes, wherein when threshold voltages for the transitions from a third state to uniform states are V 1 and -V 1 and those for the transitions from the uniform states to the third state are V 2 and -V 2 , a voltage of at least V 1 or at most -V 1 is first applied to perform switching from the third state to a uniform state, a 0 voltage is applied during a memory time period for a uniform state→third state switching to retain said uniform state and subsequently, a driving voltage of at least V 1 or at most -V 1 is applied within said memory time period for the uniform state→third state switching to select one of the uniform states.

Claim 9

A method for driving an antiferroelectric liquid crystal cell with an antiferroelectric liquid crystal or an antiferroelectric liquid crystal composition held between a pair of substrates having electrodes, said cell having dark and transmissive states as uniform states, wherein when threshold voltages for the transitions from a third state to uniform states are V 1 and -V 1 and those for the transitions from the uniform states to the third state are V 2 and V 2 , a voltage of at least V 1 or at most -V 1 is first applied to perform switching from the third state to a uniform state, a 0 voltage is applied during a memory time period for a uniform state→third state switching to retain said uniform state and subsequently, a writing pulsed voltage of at least V 1 or at most -V 1 is applied to the said cell in a period shorter than the memory time period (t), which starts just after the said voltage being turned off, for the uniform state→third state switching.

Claim 10

A method for driving an antiferroelectric liquid crystal cell with an antiferroelectric liquid crystal or an antiferroelectric liquid crystal composition held between a pair of substrates having electrodes, said cell having dark and transmissive states as uniform states, wherein when threshold voltages for the transitions from a third state to uniform states are V 1 and -V 1 and those for the transitions from the uniform states to the third state are V 2 and V 2 , a voltage of at least V 1 or at most -V 1 is first applied to perform switching from the third state to a uniform state, a 0 voltage is applied during a memory time period for a uniform state→third state switching to retain said uniform state and subsequently, a writing pulsed voltage of at least V 1 or at most -V 1 is applied to the said cell in a period shorter than the memory time period (t), which starts just after the said voltage being turned off, for the uniform state→third state switching.