Abstract: A liquid crystal apparatus comprises a liquid crystal device having a pair of substrates respectively having thereon scanning electrodes and data electrodes arranged in a matrix shape, and a liquid crystal disposed between the substrates and capable of a cumulative translational movement depending on a change in an external electric field applied to the liquid crystal; and a driver for controlling a first frequency f having a variable range and representing an effective frequency of a drive data signal pulse applied to the liquid crystal so that a second frequency f.sub.0 representing an inversion frequency at which a direction of the translational movement of the liquid crystal is turned in an opposite direction is in the variable range of the first frequency f. The above driver used in the liquid crystal apparatus is effective in suppressing a cumulative translational movement of liquid crystal molecules for a long period of time.

Abstract: A liquid crystal apparatus is constituted by a liquid crystal device including a pair of substrates and a liquid crystal disposed between the substrates, and means for applying an asymmetrical drive signal waveform to the liquid crystal. The liquid crystal is capable of having at least two stable states S1 and S2 and capable of causing a cumulative translational movement depending on a change in an external electric field applied to the liquid crystal. To the liquid crystal, an asymmetrical drive signal waveform having an effective frequency range is applied by the above application means so as to provide an absolute value of a difference between an inversion frequency f.sub.01 where a direction of the movement of said liquid crystal is turned in an opposite direction in the state S1 and an inversion frequency f.sub.

Abstract: A liquid crystal device is constituted by a pair of substrates each having thereon an electrode, and a smectic liquid crystal having a plurality of smectic liquid crystal layers disposed between the substrates. The smectic liquid crystal is disposed to form a first region wherein the smectic liquid crystal layers are aligned to have a layer inclination angle smaller than a calculated layer inclination angle based on a temperature-dependent layer spacing-changing characteristic or are aligned in a direction perpendicular to the substrates to form a bookshelf structure, and a second region wherein the smectic liquid crystal layers are aligned to form a chevron structure having a substantial layer inclination angle or having a layer inclination angle substantially equal to a calculated layer inclination angle based on a temperature-dependent layer spacing-changing characteristic.

Abstract: A liquid crystal device is constituted by a pair of oppositely disposed substrates including a first substrate provided with a first alignment control layer which has been subjected to a uniaxial aligning treatment and a second substrate provided with a second alignment control layer which has not been subjected to a uniaxial aligning treatment, a sealing member disposed so as to seal up a peripheral portion of the first and second substrates to form a spacing therebetween, and a dispersion member (e.g., spacer beads or adhesive particles) and a liquid crystal disposed in the spacing while contacting the first and second aligning control layers. The dispersion member has been subjected to a surface treatment with a material constituting the second alignment control layer. The surface-treated dispersion member is effective in suppressing an occurrence of a reverse domain within a display region of the liquid crystal device, thus preventing flickering and improving a contrast.

Abstract: A liquid crystal device is constituted by a pair of transparent substrates each having thereon a transparent electrode, and a chiral smectic liquid crystal composition disposed between the substrates so as to assume at least two optically stable states. At least one of the substrates is provided with an alignment film which comprises a polyimide represented by a recurring unit of formula (I) shown below and has been subjected to a uniaxial aligning treatment. ##STR1## wherein A denotes a planar tetravalent organic residue group comprising an aromatic ring, an aromatic polycyclic ring, a heterocyclic ring or a condensed polycyclic ring, and B denotes a divalent aliphatic group comprising .paren open-st.CH.sub.2 .paren close-st..sub.n (n: an integer of at least 1) or an alicyclic ring.

Abstract: A ferroelectric liquid crystal device of a cell structure having a suppressed increase of cell thickness along a cell side is constituted by disposing a ferroelectric liquid crystal between a pair of electrode plates each sequentially provided with an electrode, an insulating film and an alignment film on a substrate. The alignment film is provided with a surface unevenness for suppressing a liquid crystal movement causing the increase in cell thickness. The surface unevenness is provided to the alignment film directly or to the insulating film below the alignment film, e.g., by wet forming the relevant film by using at least two solvents having different boiling points or dispersing fine particles within the relevant film, optionally followed by removal of the fine particles.

Abstract: A chiral smectic liquid crystal device with good planar homogeneity in a layer normal direction can be constituted by disposing a chiral smectic liquid crystal having no cholesteric phase between a pair of substrates having mutually different characters, particularly in terms of Iso-SmA phase transition temperature. The liquid crystal may preferably have a layer spacing-changing characteristic such that it provides a layer spacing d.sub.A at a first transition point where the layer spacing of the liquid crystal begins to decrease on temperature decrease in the vicinity of a transition temperature from SmA phase to SmC* phase and a layer spacing d.sub.min at a second transition point where the layer spacing of the liquid crystal begins to increase on further temperature decrease from the first transition point, satisfying 0.96.ltoreq.d.sub.min /d.sub.A.

Abstract: A liquid crystal device is constituted by a pair of oppositely disposed substrates having opposing inner surfaces and opposing electrodes thereon, and a chiral smectic liquid crystal disposed between the opposing electrodes. The liquid crystal device has an effective optical modulation region and a peripheral region outside the effective optical modulation region. In the device, liquid crystal molecules in the peripheral region have a pretilt angle which is larger than a pretilt angle of liquid crystal molecules in the effective optical modulation region. As a result, a local pressure irregularity or a cell thickness change caused by a liquid crystal molecular movement along an extension of the device is effectively suppressed.

Abstract: A ferroelectric liquid crystal device is constituted by disposing a ferroelectric liquid crystal between a pair of substrates having thereon electrodes for voltage application and provided with uniaxial alignment axes, as by rubbing, so as to provide a high pretilt angle of at least 10 degrees. A problematic liquid crystal movement in such a high-pretilt angle ferroelectric liquid crystal device is suppressed by improving a smectic layer structure therein, inclusive of a symmetry of pretilt angles at the pair of substrate boundary surfaces. Such an improved smectic layer structure is accomplished by a realigning treatment after cooling to the chiral smectic phase or in the final stage of the cooling to the chiral smectic phase as by application of an AC electric field and/or by repetitive heating-cooling in the chiral smectic phase. The improved smectic layer structure is represented by, e.g., an X-ray diffraction peak having an increased peak area and/or a decreased half-value width.

Abstract: A liquid crystal device is constituted by a pair of oppositely disposed substrates having opposing inner surfaces and opposing electrodes thereon, and a chiral smectic liquid crystal disposed between the opposing electrodes. The liquid crystal device has an effective optical modulation region and a peripheral region outside the effective optical modulation region. In the device, liquid crystal molecules in the peripheral region have a pretilt angle which is larger than a pretilt angle of liquid crystal molecules in the effective optical modulation region. As a result, a local pressure irregularity or a cell thickness change caused by a liquid crystal molecular movement along an extension of the device is effectively suppressed.

Abstract: A ferroelectric liquid crystal device of a cell structure having a suppressed increase of cell thickness along a cell side is constituted by disposing a ferroelectric liquid crystal between a pair of electrode plates each sequentially provided with an electrode, an insulating film and an alignment film on a substrate. The alignment film is provided with a surface unevenness for suppressing a liquid crystal movement causing the increase in cell thickness. The surface unevenness is provided to the alignment film directly or to the insulating film below the alignment film, e.g., by wet forming the relevant film by using at least two solvents having different boiling points or dispersing fine particles within the relevant film, optionally followed by removal of the fine particles.

Abstract: A liquid crystal device is constituted by a pair of substrates at least one of which is provided with an alignment control film, and a liquid crystal composition disposed between the substrates and contacting the alignment control film. The alignment control film comprises an amide polymer and a pyridine-based polymer. The liquid crystal device using a mixture alignment control film described above is effective in improving a switching characteristic by minimizing a depolarization field while keeping a uniform alignment characteristic.

Abstract: A method of aligning liquid crystals includes the steps of aligning chiral smectic liquid crystal sandwiched between a pair of substrates each having an electrode by applying an alternating electric field between the substrates under periodically changing temperature conditions in which a width of changes of the temperature for a single period differs in every period.

Abstract: There is disclosed a ferroelectric liquid crystal device in which a pair of substrates and having electrodes are arranged so that the electrode surfaces face each other, a sealing agent is provided in the peripheral edge portions of the substrates, a liquid crystal injection port is opened in a part of the sealing agent, and a liquid crystal is injected from the injection port into a gap between both of the substrates. An intersection angle which is formed by the rubbing direction to orient the liquid crystal and the direction to inject the liquid crystal from the injection port lies within a range from -45.degree. to +45.degree..

Abstract: A ferroelectric liquid crystal device of a cell structure having a suppressed increase of cell thickness along a cell side is constituted by disposing a ferroelectric liquid crystal between a pair of electrode plates each sequentially provided with an electrode, an insulating film and an alignment film on a substrate. The aligment film is provided with a surface unevenness for suppressing a liquid crystal movement causing the increase in cell thickness. The surface unevenness is provided to the aligment film directly or to the insulating film below the alignment film, e.g., by wet forming the relevant film by using at least two solvents having different boiling points or dispersing fine particles within the relevant film, optionally followed by removal of the fine particles.

Abstract: A ferroelectric liquid crystal device is constituted by a pair of substrates each having thereon a group of display electrodes, and a ferroelectric liquid crystal disposed between the substrates. Liquid crystal movement causing yellowing or local increase in liquid crystal layer thickness is minimized in the device by forming a substantial in liquid crystal layer thickness between a pixel part and a non-pixel part and/or by forming a groove having minute convexities with a maximum diameter of at least 0.1 .mu.m at non-pixel parts on a substrate so that the groove extends in a direction forming an angle of 45-135 degrees with a normal to smectic layers of the liquid crystal.

Abstract: A ferroelectric liquid crystal device is constituted by a pair of substrates disposed parallel to each other and each having on its inner surface an electrode, an insulating film and an alignment control film, and a ferroelectric liquid crystal disposed between the substrates. The alignment control films on the pair of substrates are provided with uniaxial alignment axes in directions which are substantially parallel and opposite to each other. The ferroelectric liquid crystal is placed in an alignment state showing a pretilt angle .alpha. of 5 degrees <.alpha.<45 degrees formed by transition from a bistable state giving a lower apparent tilt angle to a bistable state giving a higher apparent tilt angle, the action of mechanical or electrical means, such as application of ultrasonic treatment, static load or AC electric field.

Abstract: There is provided a ferroelectric liquid crystal device wherein the yellowing due to a cell thickness increase or occurrence of voids is suppressed. The ferroelectric liquid crystal device includes a pair of substrates each having thereon a group of electrodes for liquid crystal drive, and a layer of ferroelectric liquid crystal disposed between the substrates, wherein thermosetting adhesive particles and thermoplastic polymer particles having a diameter which is 1.5-5 times the liquid crystal layer thickness are dispersed and pressed between the substrates. The polymer particles preferably have a glass transition temperature of at most -20.degree. C.

Abstract: A chiral smectic liquid crystal device is constituted by a chiral smectic liquid crystal, and a pair of substrates sandwiching the liquid crystal with their opposite surfaces that are provided with electrodes for applying a voltage to the liquid crystal and uniaxial alignment axes which are parallel or substantially parallel to each other and identical in direction. The liquid crystal device is provided with excellent bistability and freeness from "burning" if the liquid crystal is placed in the alignment state characterized in that (A) a relationship of .alpha.<H is satisfied, wherein a denotes a pretilt angle and H denotes a tilt angle, respectively, of the liquid crystal and (B) the liquid crystal provides at least two stable states of optical axes which form an angle 2.theta.a therebetween satisfying H>.theta.a>H/2.

Abstract: A ferroelectric liquid crystal device is constituted by disposing a ferroelectric liquid crystal between a pair of substrates having thereon electrodes for voltage application and provided with uniaxial alignment axes, as by rubbing, so as to provide a high pretilt angle of at least 10 degrees. A problematic liquid crystal movement in such a high-pretilt angle ferroelectric liquid crystal device is suppressed by improving a smectic layer structure therein, inclusive of a symmetry of pretilt angles at the pair of substrate boundary surfaces. Such an improved smectic layer structure is accomplished by a realigning treatment after cooling to the chiral smectic phase or in the final stage of the cooling to the chiral smectic phase as by application of an AC electric field and/or by repetitive heating-cooling in the chiral smectic phase. The improved smectic layer structure is represented by, e.g., an X-ray diffraction peak having an increased peak area and/or a decreased half-value width.