Abstract: Chiral nonracemic molecules which are useful as high tilt, high polarization and/or high birefringence FLC materials or are useful as components of such FLC materials and which have the following general structure are provided:RO--(Ph.sub.1).sub.m --(A).sub.a --(Ph.sub.2).sub.n --(B).sub.b --(Ph.sub.3).sub.p --Twhere Ph.sub.1, Ph.sub.2 and Ph.sub.

Abstract: A system for producing modulated light is disclosed. The system comprises a spatial light modulator including a light modulating medium switchable between different states so as to act on light in ways which form overall patterns of modulated light. The system also includes an arrangement for switching the modulating medium between the different states in a controlled way and an illumination arrangement for producing a source of light. The system further includes an optics arrangement for directing light from the source of light into the spatial light modulator and for directing light from the spatial light modulator through a predetermined source imaging area. The optics arrangement cooperates with the illumination arrangement and the spatial light modulator so as to produce a real image of the source of light within the source imaging area such that an individual is able to view a virtual image of the overall patterns of modulated light from the source imaging area.

Abstract: A system and method for producing spatially modulated monochrome or color light having gray scale during a given period of time includes a spatial light modulator having a light modulating arrangement switchable between different states so as to act on light in different ways. A switching arrangement switches the modulating arrangement between different states in a controlled way during the period. The system also includes an illumination arrangement for selectively and alternately directing light of constant intensity and varying intensity into the modulating arrangement during predetermined subperiods of the period. In a color version of the system, the illumination arrangement directs light of different colors into the modulating arrangement during predetermined subperiods of the period, thereby providing a system for producing modulated colored light having color gray scale during a given period.

Abstract: Ferroelectric Liquid Crystals (FLCs) which exhibit a ferroelectric phase and a chiral nematic phase at temperatures above the ferroelectric phase are provided. The natural helix pitch of the FLC in the ferroelectric phase of these materials is sufficiently tighter than the thickness of the FLC layer such that it is not surface-stabilized. The chiral nematic phase has a natural helix pitch sufficiently greater than the cell thickness to facilitate alignment of the FLC in an FLC device to achieve high contrast. The FLCs of this invention are useful in making fast response, high contrast FLC electro-optic devices in which the FLC retains a helical director structure stable to unwinding.

Abstract: A system for producing spatially modulated monochrome or color light having gray scale includes an active matrix liquid crystal spatial light modulator having light modulating means including (i) a layer of ferroelectric liquid crystal material which is designed to switch between ON and OFF states and (ii) active matrix means including VLSI circuitry for dividing the layer of liquid crystal material into an array of individual liquid crystal pixels and for causing each of the pixels of liquid crystal material to modulate light individually by switching between the ON and OFF states in a way that depends upon the data which the VLSI circuitry is written. The system also includes illumination means having a light source for directing light from the source into the pixel-divided layer of ferroelectric liquid crystal material in a specific way.

Abstract: An active matrix liquid crystal display includes an arrangement for maintaining the liquid crystal material of the display at a controlled temperature above ambient temperature. The liquid crystal material of the display is disposed over a substrate containing integrated circuitry. The arrangement for maintaining the temperature of the liquid crystal includes (i) an arrangement for heating the liquid crystal material sufficient to maintain the liquid crystal material at the controlled temperature, (ii) an arrangement for sensing the temperature at a location in close proximity to the liquid crystal material and producing an output signal representative of the temperature, and (iii) a servo-circuit responsive to the output signal for causing the heating arrangement to maintain the liquid crystal material at the controlled temperature.

Abstract: High birefringence liquid crystal dopants having the formula:R.sub.1 X--C--.tbd.--D--Twherein C and D, independently of one another, are aromatic ring systems each of which has one or two 5-member or 6-member carbon rings wherein one or two carbons of any ring in C or D can be substituted with a nitrogen, oxygen or sulfur atom and wherein any ring in C or D can be substituted with one or two halogen atoms; T is a halogen, haloalkyl, haloalkoxy, vinylhalide or a group YR.sub.2 where Y is a single bond, double bond, triple bond, --COS--, --CS.sub.2 --, --CH.dbd.CH--CO--S--, --CH.dbd.CH--CS--S-- or --CH.dbd.CH--CO--O-- group; X is a single bond, double bond, triple bond, O or S atoms or a cyclohexane or cyclohexene group, Z--Q--W, where Q is a cyclohexane or cyclohexene ring in which one or two of the ring carbons can be replaced with an O atom or in which one or more of the ring carbons can be substituted with a halogen atom or a cyano group, Z is a single bond or an O or S atom and W is a single bond, a --CH.

Abstract: An assembly for producing a visual display includes a light-reflecting type spatial light modulator and an illumination arrangement for providing a particular source of light. The spatial light modulator has a light reflecting surface cooperating with a light modulating medium switchable between different states so as to act on light in ways which form an overall pattern of reflected, modulated light. The spatial light modulator also has an arrangement for switching the modulating medium between the different states in a controlled way so as to form the overall pattern. The overall assembly further includes an optics arrangement having a first member defining a light reflecting surface.

Abstract: This invention provides chiral nonracemic compounds of general formula I which are useful as components of FLC compositions in SSFLC and DHFLC devices: ##STR1## wherein Z is a C.dbd.O group or a CH.sub.2 group, R.sub.F is a partially or fully fluorinated alkyl or alkenyl group, R.sub.2 is selected from an alkyl, alkenyl or alkynyl group in which one or more CH.sub.2 groups can optionally be substituted with one or two halogen atoms or in which one or more non-neighboring CH.sub.2 can be replaced with an O, S or an alkyl silyl group, S.sub.1 (R.sub.A)(R.sub.B), in which R.sub.A and R.sub.B, independently of one another, are small alkyl or alkenyl groups having from one to six carbon atoms, * indicates the chiral carbon and where Ar can be a one, two, or three aromatic ring LC core moieties. In particular, the core can have one to three, aromatic rings which are optionally linked by linking groups including O, S, CH.sub.2 S, SCH.sub.2, CH.sub.2 CH.sub.2, CH.sub.2 O, OCH.sub.2, CH.sub.2 CO.sub.2, CH.sub.

Abstract: An arrangement (apparatus and method) for selectively modulating incident unpolarized light passing through a birefringent material, such as ferroelectric crystal. The apparatus includes a plate having one or more birefringent layers corresponding to first and second alignment regions. The birefringent layer corresponding to the first alignment region has a first optic axis selectably set in a first orientation and a second orientation. The birefringent layer corresponding to the second alignment region has a second optic axis selectably set in a third orientation and a fourth orientation. A switching means controls the optical axis states of the birefringent material by applying switching voltages to the areas of the birefringent layer. Light having passed through the birefringent layer at locations having the first orientation has a different phase from, and same polarization as, light having passed through locations with the third orientation, independent of a polarization state of the incident light.

Abstract: Fast response, high contrast Ferroelectric Liquid Crystal (FLC) electro-optic devices in which the FLC retains a helical director structure stable to unwinding are provided. In particular, high contrast distorted helix FLC electro-optic devices including half-wave plates in the visible wavelength region are provided. The FLC cells of this invention incorporate chiral FLCs which exhibit a ferroelectric phase and a chiral nematic phase at temperatures above the ferroelectric phase. The natural helix pitch of the FLC in the ferroelectric phase is sufficiently tighter than the thickness of the FLC layer such that it is not surface-stabilized. The chiral nematic phase has a natural helix pitch sufficiently greater than the cell thickness to facilitate alignment of the FLC in the device to achieve high contrast.

Abstract: There is disclosed herein a liquid crystal spatial light modulator which is driven y an analog input voltage and which includes, among other components, a layer of liquid crystal material that changes the way in which it acts on light in response to predetermined changes in voltage across the layer, whereby to modulate the light so acted upon, and an arrangement for applying a light modulating voltage across the layer of liquid crystal material and for modulating the voltage during a given modulation period. This latter arrangement includes a non-linear capacitor and a voltage coupling scheme for changing the voltage across the capacitor during the modulation period in a way which changes the capacitance of the capacitor and thereby capacitively couples at least a part of the change in voltage across the capacitor to the layer of liquid crystal material.

Abstract: There is disclosed herein a liquid crystal spatial light modulator which includes, among other components, a layer of liquid crystal material which changes the way in which it acts on light in response to predetermined changes in voltage across the layer, whereby to modulate the light so acted upon, and an arrangement for applying a light modulating voltage across the layer of liquid crystal material and for modulating the voltage during a given modulation period. This latter arrangement includes a non-linear capacitor and a voltage coupling scheme for changing the voltage across the capacitor during the modulation period in a way which changes the capacitance of the capacitor and thereby capacitively couples at least a part of the change in voltage across the capacitor to the layer of liquid crystal material.

Abstract: The present invention provides liquid crystals that are diphenyldiacetylenes of the general formulas: ##STR1## where W, X, Y and Z are, independently of one another, a halogen atom, a hydrogen atom or a trihalomethyl group, T.sub.1 and T.sub.2, independently of one another can be an alkyl, alkene, alkoxy, alkenoxy, ether, thioalkyl, thioalkenyl, haloalkyl, haloalkoxy or haloalkylether groups having from three to twenty carbon atoms or a silylalkyl, silylalkenyl, silylalkoxy or silylthioalkyl group having from three to twenty-eight carbon atoms and wherein M.sub.1 and M.sub.2 can both be single bonds or one of M.sub.1 or M.sub.2 can be a trans-1,4-cyclohexylene or a --CH.sub.2 CH.sub.2 -trans-1,4-cyclohexylene.

Abstract: This invention provides chiral nonracemic compounds of formula ##STR1## wherein * indicates a chiral carbon, R.sub.1 and R.sub.2, independently of one another, can be an alkyl, alkenyl or alkynyl group wherein one or more non-neighboring CH.sub.2 groups can be replaced with an O, S or a silyl group (R.sub.A SiR.sub.B) wherein R.sub.A and R.sub.B, independently of one another, are alkyl or alkenyl having from one to six carbon atoms; R.sub.1 having from about 3 to 20 carbon atoms, and R.sub.2 having from 1 to about 18 carbon atoms; X is O, S, CO, COO, OCO, COS or a single bond where Ar is a liquid crystal core moiety having two or three aromatic rings of the formula--(Cyc).sub.n --(A).sub.a --Ph.sub.1 --(B).sub.b --Ph.sub.2 --(C).sub.c --(Ph.sub.3).sub.m --whereinPh.sub.1, Ph.sub.2 and Ph.sub.

Abstract: The subject application discloses chiral nonracemic compositions of the general formula: ##STR1## wherein R.sub.1 is an achiral tail of two to sixteen carbons; Ar is an achiral FLC core of at least two rings; * denotes a chiral or potentially chiral carbon; Q and D are H or a methyl group, provided that q and D are not both methyl; X and Z are halides and Y is H or a halide; and R.sub.2 is one to ten carbon atoms. The --O--C*HQ--C*DX--C*HY-- segment comprises the chiral proximal segment of the chiral tail. Z can be an ortho halide alone, or ortho and meta halides on adjacent carbons on the aromatic ring of the core adjacent to the proximal segment. R.sub.2 is the distal segment of the chiral tail.

Abstract: A family of optical switches employ dielectric film polarizing beam splitters and switchable electro-optic retarder to produce 2.times.2 optical switches which exhibit low crosstalk characteristics while switching unpolarized or linearly polarized collimated light. The switches all contain four port modules through which light enters and leaves the switch. The port modules utilize polarizing beam splitters to separate incoming light into two orthogonal linearly polarized components. The component beams are made parallel after which each passes through an electro-optic retarder. The retarders are electrically driven so as to selectively change the polarization of either one of the two component beams, thus making the polarizations the same. Other polarizing beam splitters are disposed to direct the component beams along one of two pairs of paths as determined by their common polarization.

Abstract: Chiral, nonracemic compounds of the general formula: ##STR1## wherein m and n are either both zero, both equal one or n is equal to one and m is equal to zero, X and Y and Z are halogens, R' is an alkyl, alkoxyl, alkenyl, thioalkyl, thioether, ether, or alkylsilyl group containing three to fifteen carbon atoms, and R is an alkyl group having one to fifteen carbon atoms and where Ar is:--A.sub.a --(E).sub.e --B.sub.b --(F).sub.f --D.sub.d --where A, B and D independently of one another are aromatic rings which are selected from the group consisting of a phenyl, a pyridine ring, a pyrimidine ring, a pyridizine ring, a pyrazine ring and a thiadiazole ring, wherein a, b and d are integers from 0-3 such that a+b+d=2-3, where E and F independently of one another are linking groups selected from the group consisting of a --CH.sub.2 --CH.sub.2 --, --CH.sub.2 --O--, --CH.sub.2 --S--, --O--CH.sub.2 --, --S--CH.sub.

Abstract: A frame-sequential color video system and color-selective filters for use in the same. The color-selective filters of the invention have fast response, and can be switched between the three primary colors of red, green, and blue. Switching between the three primary colors is achieved by selective absorption, or by selective interference, which is controlled by the switching of specific device combinations. A frame-sequential color display system is achieved by combining such a color-selective filter with a fast-switching black and white video display, which can be either emissive or reflective. A frame-sequential color camera system is achieved by combining such a color-selective filter with a fast-responding black and white video camera.

Abstract: The subject application discloses a chiral nonracemic composition of the general formula:R.sub.1 --Ar--O--CH.sub.2 --C*HX--C*HY--CH.sub.2 --O--R.sub.2wherein R.sub.1 is an achiral tail of two to sixteen carbons; Ar is an achiral FLC core of at least two rings; * denotes a chiral carbon; X and Y are halogens; and R.sub.2 is one to ten carbon atoms. The --O--CH.sub.2 --C*HX--C*HY--CH.sub.2 --O-- segment comprises the chiral proximal segment of the chiral tail; the proximal segment is selected from the enantiomers 2R,3R-dihalo and 2S,3S-dihalo. R.sub.2 is the distal segment of the chiral tail.