Abstract: In a method of operating a liquid crystal device having a liquid crystal composition with smectic-A properties, a first waveform is applied to optically clear the device so that it is substantially transparent to visible light and a second waveform is applied to disorder the material of the liquid crystal composition to afford a strongly light-scattering state. The first waveform has a higher frequency than the second, waveform, and the method comprises applying a modified waveform to partially clear at least a portion of the device from the light-scattering state.

Abstract: A liquid crystal smectic A composition that can be switched by the application of different electric fields across it between a first stable state (left hand block in FIG. 4) and at least one second stable state (right hand block in FIG. 4) in which the composition is less ordered than in the first state. The radiation transmission properties of the first and second states are different.

Abstract: In a method of operating a liquid crystal device having a liquid crystal composition with smectic-A properties, a first waveform is applied to optically clear the device so that it is substantially transparent to visible light and a second waveform is applied to disorder the material of the liquid crystal composition to afford a strongly light-scattering state.

Abstract: The present, invention relates to liquid crystal compositions having a smectic A structure for use in an optical device in which the composition is sandwiched between a pair of electrodes (12-15). In essence the composition includes a siloxane oligomer (component (a)) which may be seen to construct a layered SmA system of particular spacing and “strength”. Within this structure a low molar mass nematic mesogen (component (c)) is provided that may be considered to be that of a “plasticiser” which moderates the layer “strength”, while simultaneously providing tuneability to the properties of the composition, e.g. its refractive index or dielectric anisotropy. The addition of a side chain liquid crystal polysiloxane (component (d)) allows such systems to be further moderated since they can be considered as binding together the la>¾rs, both within a given layer and between layers.

Abstract: A liquid crystal formulation is described. The liquid crystal formulation comprises a first oligosiloxane-modified nano-phase segregating liquid crystalline material; and at least one additional material selected from a second oligosiloxane-modified nano-phase segregating liquid crystalline material, non-liquid crystalline oligosiloxane-modified materials, organic liquid crystalline materials, or non-liquid crystalline materials, wherein the liquid crystal formulation has an I?SmA*?SmC* phase transition, with a SmC* temperature range from about 15° C. to about 35° C., a tilt angle of about 22.5°±6° or about 45°±6°, a spontaneous polarization of less than about 50 nC/cm2., and a rotational viscosity of less than about 600 cP. Devices containing liquid crystal formulations are also described.

Abstract: A liquid crystal smectic A composition that can be switched by the application of different electric fields across it between a first stable state (left hand block in FIG. 4) and at least one second stable state (right hand block in FIG. 4) in which the composition is less ordered than in the first state. The radiation transmission properties of the first and second states are different.

Abstract: The present, invention relates to liquid crystal compositions having a smectic A structure for use in an optical device in which the composition is sandwiched between a pair of electrodes (12-15). In essence the composition includes a siloxane oligomer (component (a)) which may be seen to construct a layered SmA system of particular spacing and “strength”. Within this structure a low molar mass nematic mesogen (component (c)) is provided that may be considered to be that of a “plasticiser” which moderates the layer “strength”, while simultaneously providing tuneability to the properties of the composition, e.g. its refractive index or dielectric anisotropy. The addition of a side chain liquid crystal polysiloxane (component (d)) allows such systems to be further moderated since they can be considered as binding together the la>¾rs, both within a given layer and between layers.

Abstract: A liquid crystal formulation is described. The liquid crystal formulation comprises a first oligosiloxane-modified nano-phase segregating liquid crystalline material; and at least one additional material selected from a second oligosiloxane-modified nano-phase segregating liquid crystalline material, non-liquid crystalline oligosiloxane-modified materials, organic liquid crystalline materials, or organic non-liquid crystalline materials, wherein the liquid crystal formulation is nano-phase segregated in the SmC* phase, has an I?SmC* phase transition, with a SmC* temperature range from about 15° C. to about 35° C., has a tilt angle of about 22.5°±6° or about 45°±6°, and has a spontaneous polarization of less than about 50 nC/cm2, and a rotational viscosity of less than about 600 cP. Devices containing liquid crystal formulations are also described.

Abstract: A liquid crystal electro-optic device. The liquid crystal electro-optic device comprises at least one liquid crystal cell comprising: a pair of substrates having a gap therebetween; a pair of electrodes, the pair of electrodes positioned on one of the substrates or one electrode positioned on each substrate; and a ferroelectric, oligosiloxane liquid crystal material disposed in the gap between the pair of substrates, the ferroelectric, oligosiloxane liquid crystal material exhibiting an I-? SmC* phase sequence wherein the liquid crystal electro-optic device is bistable in operation. The invention also involves a method for making a liquid crystal electro-optic device.

Abstract: A liquid crystal structure (200) comprising first and second reflective regions (214a, 214b, 214c) arranged to reflect respective first and second colours. The first and second reflective regions (214a, 214b, 214c) are disposed transversely to the direction of reflection (R). Each region includes a reflective back area and a selector (210) controllable to control light reflected from the region. Furthermore, a controllable reflector (212) is superposed over the reflective region in the direction of reflection (R) and controllable to transmit or scatter incident light.

Abstract: A liquid crystal formulation is described. The liquid crystal formulation comprises a first oligosiloxane-modified nano-phase segregating liquid crystalline material; and at least one additional material selected from a second oligosiloxane-modified nano-phase segregating liquid crystalline material, non-liquid crystalline oligosiloxane-modified materials, organic liquid crystalline materials, or organic non-liquid crystalline materials, wherein the liquid crystal formulation is nano-phase segregated in the SmC* phase, has an I?SmC* phase transition, with a SmC* temperature range from about 15° C. to about 35° C., has a tilt angle of about 22.5°±6° or about 45°±6°, and has a spontaneous polarization of less than about 50 nC/cm2, and a rotational viscosity of less than about 600 cP. Devices containing liquid crystal formulations are also described.

Abstract: A liquid crystal formulation is described. The liquid crystal formulation comprises a first oligosiloxane-modified nano-phase segregating liquid crystalline material; and at least one additional material selected from a second oligosiloxane-modified nano-phase segregating liquid crystalline material, non-liquid crystalline oligosiloxane-modified materials, organic liquid crystalline materials, or non-liquid crystalline materials, wherein the liquid crystal formulation has an I?SmA*?SmC* phase transition, with a SmC* temperature range from about 15° C. to about 35° C., a tilt angle of about 22.5°±6° or about 45°±6°, a spontaneous polarization of less than about 50 nC/cm2., and a rotational viscosity of less than about 600 cP. Devices containing liquid crystal formulations are also described.

Abstract: A liquid crystal electro-optic device. The liquid crystal electro-optic device comprises at least one liquid crystal cell comprising: a pair of substrates having a gap therebetween; a pair of electrodes, the pair of electrodes positioned on one of the substrates or one electrode positioned on each substrate; and a ferroelectric, oligosiloxane liquid crystal material disposed in the gap between the pair of substrates, the ferroelectric, oligosiloxane liquid crystal material exhibiting an I-? SmC* phase sequence wherein the liquid crystal electro-optic device is bistable in operation. The invention also involves a method for making a liquid crystal electro-optic device.

Abstract: A liquid crystal structure (200) comprising first and second reflective regions (214a, 214b, 214c) arranged to reflect respective first and second colours. The first and second reflective regions (214a, 214b, 214c) are disposed transversely to the direction of reflection (R). Each region includes a reflective back area and a selector (210) controllable to control light reflected from the region. Furthermore, a controllable reflector (212) is superposed over the reflective region in the direction of reflection (R) and controllable to transmit or scatter incident light.

Abstract: A display device includes a shutter layer of liquid-crystal material arranged in cells to shutter input light selectively, a cover layer 5 on the shutter layer, and a set of phosphors 7 on the cover layer, corresponding to the cells, to be activated by the input light and provide the display image. To prevent crosstalk the active cell areas 10 defined by the electrode overlaps are smaller than the corresponding phosphors. This prevents crosstalk between cells even when input light that is not fully collimated is used and also allows space for thicker and/or broader electrodes 12 leading to the cells, reducing resistance, and for other components such as TFTs.