Abstract: A large area liquid crystal display comprises a layer of liquid crystal material between two cell walls. One cell wall has a common sheet electrode. The other cell walls comprise a plurality of addressing tiles electrically connected together. Driver circuits at the display edges apply addressing voltages. Each addressing tiles comprises a series of m data electrodes and n gate electrodes arranged to form an m×n matrix array of electrode intersections. At each intersection is a pixel patch electrode and a non linear element connected to adjacent source and gate electrodes and to the pixel electrode. The data and gate electrodes continue across the tile surface and around its edges. Adjacent tiles are electrically connected together by an anisotropic glue, or by solder bumps, or electrical bridges. The liquid crystal material may be encapsulated in a polymer matrix or be a non-encapsulated layer. Dyes may be incorporated in the liquid crystal material.

Abstract: Ferroelectric liquid crystal devices having two spaced cell walls each bearing electrode structures and treated on at least one facing surface with an alignment layer, and a layer of a smectic liquid crystal material enclosed between the cell walls, exhibits a minimum in its response time versus voltage curve. The crystal material has two components, A and B.

Abstract: Ferroelectric liquid crystal devices are described which contain liquid crystal mixtures comprising components A and B. Component A consists of one or more optically active compounds capable of imparting a spontaneous polarization to the material. Component B is selected as one or more compounds having formula (I), wherein a, b and c are independently 0, 1, 2; R.sub.1 and R.sub.2 are C.sub.1-15 straight or branched chain alkyl or alkoxy, preferably C.sub.3-12. In the above (for component B) CH=CH linking groups may be replaced by C.sub.2 H.sub.4 and CH.sub.2 O linking groups may be replaced by OCH.sub.2.

Abstract: A nematic liquid crystal device with two bistable switched states, having two cell walls treated which provide a bigrating on one or both cell walls. The bigrating enables the liquid crystal molecules at a surface to lie in two different angular directions, 45 or 90 degrees apart. The bigrating may be symmetric or asymmetric, with the surface energy of each of the gratings of the bigratings being nearly equal.

Abstract: A liquid crystal polymer or copolymer is disclosed of structure (A) where X=CN, COR, CO.sub.2 R, CHO, CF.sub.3 ; R=branched chain, straight chain or chiral alkyl; .rect-hollow.=any suitable mesogenic group; Z=single covalent bond, oxygen, sulfur, CO.sub.2 or OCO; n=1 to 20; Y=H, OH, F, OCH.sub.3 ; m=3 to 200; P=a single covalent bond, oxygen, or OCO.

Abstract: Multiplex addressed ferroelectric liquid crystal devices containing liquid crystal mixtures composed of components A, B and C. Component A consists of one or more optically active compounds capable of imparting a spontaneous polarization to the material. Component B is a compound or compounds of the formula: ##STR1## where R.sub.1 and R.sub.2 independently represent straight or branched chain C.sub.3 -C.sub.12 alkyl or alkoxy groups, a, b and c are independently 0, 1 or 2 and the total of a+b+c is not greater than 4. Component C is selected from a range of liquid crystal components.

Abstract: Liquid crystal compounds of the formula:R.sup.1 --Z.sup.1).sub.m --(Z.sup.2)--X--(Z.sup.3)--(Z.sup.4).sub.n --R.sup.2These compounds may be mixed with other liquid crystal compounds to give liquid crystal mixtures which may then be used in liquid crystal devices. In the formula X is COS, CSS and CSO; each of Z.sup.1, Z.sup.2, Z.sup.3, and Z.sup.4 are independently phenyl, substituted phenyl, where substitution is lateral substitution selected from F, Cl, Br, NO.sub.2, CN, NCS; naphthalene, substituted naphthalene, where substitution is lateral substitution selected from F, Cl, Br, NO.sub.2, CN, NCS, CH.sub.3 ; thiophene, pyridine and pyrimidine; each of A.sup.1 and A.sup.2 is independently selected from single bond, C.tbd.C, CH.dbd.CH; A.sup.3 is selected from C.tbd.C and single bond; each of R.sup.1 and R.sup.2 are independently selected from CN, NCS, CH.dbd.C(CN).sub.2, C.tbd.C--CN, C.tbd.C--CF.sub.

Abstract: Liquid crystal compounds of formula (I) are described, where formula (I) is given as R.sub.1 --A--(X.sub.m --(B).sub.n --R.sub.2 where A is selected from nathyl, flourinated naphthyl, brominated naphthyl, B is selected from phenyl, methylated phenyl, brominated phenyl, fluorinated phenyl, thiophene, pyrimidine and pyridine, R.sub.1 and R.sub.2 are independently selected from alkyl, alkoxy, alkynyl, thioalkyl, Br, CN, SCN, NCS, perfluoroalkyl, perfluoroalkoxy and hydrogen, X is selected from C.tbd.C, COO and C.tbd.C, m is 0 or 1, n is 0 or 1 where m is 1 and n is 0 where m is 0; provided that where A is naphthyl, n is 1 and m is 0 then B is selected from methylated phenyl, brominated phenyl, thiophene, pyrimidine and pyridine; and further provided that where A is naphthyl, X is C.tbd.C, m is 1 and n is 1, then B is selected from thiophene, pyrimidine and pyridine.

Abstract: Compounds of formula (I) where R is C.sub.1-15 alkyl, X is hydrogen, fluorine or chlorine, m and n are independently selected 1 or 0, W is C.sub.1-15 alkyl or alkoxy, CN or halogen, rings A and B Are independently selected from phenyl, laterally fluoro- or chloro- substituted phenyl, transcyclohexyl pyridyl, pyrimidyl or dioxanyl. Preferred embodiments have R=C.sub.3-8 and where W is alkyl or alkoxy then it is also preferable that W=C.sub.3-8. Where m=0, then preferably W=CN and where m=1, then preferably W=alkyl.

Abstract: Novel compounds of formula (I), in which R is R.sup.1, R.sup.1 O or R.sup.1 COO, where R.sup.1 is C.sub.1-12 alkyl, n and m are 0 or 1 provided that (n+m) is 0 or 1, each of a, b, c and d are independently 0 or 1, provided (a+b+c+d) is not zero, but excluding the case where a and b are 0 and m is 0 and one of c or d is 0 are described, being useful constituents of nematic liquid crystal materials.

Abstract: A color display formed of information of one color on a different color background is projected onto a screen. Light from the bulb is passed serially through a neutral polarizer, a smectic liquid crystal cell, and a further polarizer. The cell comprises a smectic liquid crystal material incorporating an amount of a cholesteric material and a dye contained between two cell walls carrying electrodes and surface treated to give a molecular twist and alignment to the liquid crystal material. Information is written into the cell by scanning the laser beam over the cell, causing localized heating, in combination with or without an applied electric field to form selected areas with a twisted structure on a background of homeotropic structure, or vice versa. Thus plane polarized light is passed through the cell with its plane selectively rotated or non rotated. This provides a two color display of information of one color on a background of the other color.

Abstract: Laterally fluorinated 4-cyanophenyl and 4'-cyanobiphenyl benzoates are diosed of general formula I: ##STR1## in which R is R.sup.1 or R.sup.1 O, wherein R.sup.1 is C.sub.1 -C.sub.12 alkyl, m and n are 0 or 1 provided that (n+m) is 0 or 1, each of a, b, c and d are independently 0 or 1, provided (a+b+c+d) is not zero, but excluding the case where a and b are 0 and one of c and d is 0, being useful constituents of nematic liquid crystal materials.

Abstract: A thermochromic liquid crystal display comprises a layer of short pitch cholesteric liquid crystal material between two walls. An absorber covers the back of the rear wall. At least one wall is surface profiled with a fine grating to align the liquid crystal material. Typically the grating pitch is 0.05 to 12 .mu.m. The profile may be fine on one wall e.g. 0.05 to 12 .mu.m pitch, 0.1 .mu.m depth and coarse e.g. 125 .mu.m pitch groove width 100 .mu.m, depth 10 .mu.m on the other wall. The cholesteric pitch is arranged to give the desired a selective reflection of light whereby the display is observed to change color with temperature. Using thin flexible walls small displays may be cut from large sheets of embossed polyester plastic materials.

Abstract: A novel method of preparing thermochromic liquid crystal mixtures is provided in which mixtures which show an injected smectic phase at lower temperatures than their thermochromic cholesteric phase are prepared, and by following the envelope of the injected smectic - cholesteric transition on the phase diagram a series of thermochromic compositions containing the same components but having a series of working temperature ranges are obtained.Novel thermochromic liquid crystal mixtures prepared using the method are also provided.

Abstract: A metal dithiene of the formula: ##STR1## wherein R.sup.1 is C.sub.3 to C.sub.20 alkyl;R.sup.2 is selected from alkyl, alkylamino, dialkylamino, alkylthio and alkoxy in which each alkyl contains up to 20 carbon atoms;R.sup.3 is H, halogen or a group represented by R.sup.2 ; andM is a metal selected from Groups Ib, IIb, VIIb, and VIIIb of the Periodic Table,and a composition of the metal dithiene in a liquid crystal medium. The composition is suitable for use in a light valve for a laser-addressed liquid crystal display.

Abstract: A fluorinated compound having a formula: ##STR1## R.sub.1 is hydrogen or alkyl having up to 12 carbon atoms; R.sub.2 is selected from hydrogen, alkyl having up to 12 carbon atoms, alkoxy having up to 12 carbon atoms, ##STR2## wherein R.sub.3 is hydrogen or alkyl having up to 12 carbon atoms, and wherein R.sub.4 is hydrogen, alkyl having up to 12 carbon atoms or alkoxy having up to 12 carbon atoms; ##STR3## represents a cyclohexane ring which is in the trans configuration if 1, 4-disubstituted; ##STR4## represents a benzene ring; each of X, Y and Z independently represents hydrogen or fluorine in one or more of the lateral benzene ring positions, provided that at least one of X, Y and Z is present representing fluorine;n=0 or 1 provided that when n=0 ##STR5## and R.sub.1 is alkyl; with the proviso that in Formula I when n is 1 and ##STR6## where R.sub.1 is n-alkyl and R.sub.2 is n-alkyl or n-alkoxy the total number of carbon plus oxygen atoms in the two groups R.sub.1 and R.sub.2 is less than 10.

Abstract: A metal dithiene of the formula: ##STR1## wherein R.sup.1 is C.sub.3 to C.sub.20 alkyl;R.sup.2 is selected from alkyl, alkylamino, dialkylamino, alkylthio and alkoxy in which each alkyl contains up to 20 carbon atoms;R.sup.3 is H, halogen or a group represented by R.sup.2 ;and M is a metal selected from Groups Ib, IIb, VIIb, and VIIIb of the Periodic Table,and a composition of the metal dithiene in a liquid crystal medium. The composition is suitable for use in a light valve for a laser-addressed liquid crystal display.

Abstract: A liquid crystal composition suitable for use as a two-frequency material in a two-frequency switching device comprises a mixture of:a first component comprising at least one diester compound having a formula: ##STR1## where R.sub.1 is an alkyl or alkoxy group, Z is an cycloalkyl or aryl ring structure and R.sub.2 is alkyl, alkoxy or halogen; or CN; and a second component comprising at least one compound having a formula: ##STR2## wherein R.sub.3 and R.sub.4 is each independently an alkyl or alkoxy group, ##STR3## is a trans-1,4-disubstituted cyclohexane or a benzene ring, Y is a cycloalkyl ring or a benzene ring optionally having a lateral halogen substituent and n is 0 or 1.

Abstract: Liquid crystal compositions are described which comprise a mixture of compounds and which includes at least one additive compound characterized in that the composition includes one or more additive compounds of Formula I as follows: ##STR1## wherein R.sub.1 represents an alkyl group, R.sub.2 represents an alkyl or alkoxy group or hydrogen and ##STR2## represents a 1,4-disubstituted bicyclo(2,2,2)octane ring. The preparation and properties of novel compounds of Formula I are also described. These liquid crystal compositions are useful in display devices such as digital calculators and word displays.