The invention relates to a light modulation element as comprising, preferably consisting of a cholesteric liquid crystalline medium sandwiched between two opposing substrates, an electrode arrangement, which is capable to allow the application of an electric field, which is substantially perpendicular to the main plane of substrate or the layer of the cholesteric liquid crystalline medium, characterized in that one of the substrates is provided with a planar alignment layer adjacent to the cholesteric liquid crystalline medium and the other substrate is provided with a homeotropic alignment layer adjacent to the cholesteric liquid crystalline medium. The invention is further related to a method of production of said light modulation element and to the use of said light modulation element in various types of optical and electro-optical devices, such as electro-optical displays, liquid crystal displays (LCDs), non-linear optic (NLO) devices, and optical information storage devices.

The invention relates to bimesogenic compounds of formula I

##STR00001##

wherein R.sup.11, R.sup.12, MG.sup.1, MG.sup.2, X.sup.11, X.sup.12 and Sp.sup.1 have the meaning given in claim 1, to the use of bimesogenic compounds of formula I in liquid crystal media and in particular to flexoelectric liquid crystal devices comprising a liquid crystal medium according to the present invention.

The invention relates to mesogenic media comprising one or more bimesogenic compounds, one or more nematogenic compound, one or more chiral compound and a compound of formula I,
R.sup.11-A.sup.11-(Z.sup.12-A.sup.12).sub.m-AGI
in which, the parameter A.sup.11, A.sup.12, Z.sup.12 and R.sup.11 have one of the meanings as given in claim 1, and to the use of these mesogenic media in liquid crystal devices and in particular in flexoelectric liquid crystal devices, as well as to liquid crystal devices comprising a liquid crystal medium according to the present invention.

The invention relates to bimesogenic compounds of formula I

##STR00001##

wherein R.sup.11, R.sup.12, MG.sup.11, MG.sup.12, X.sup.11, X.sup.12 and Sp.sup.1 have the meaning given in claim 1, to the use of bimesogenic compounds of formula I in liquid crystal media and particular to flexoelectric liquid crystal devices comprising a liquid crystal medium according to the present invention.

The invention relates to a device for the regulation of light transmission, preferably a window, more preferably a privacy window, comprising a liquid crystalline medium exhibiting a converse flexoelectric effect, and which is sandwiched between two substrates, wherein at least one substrate is provided with an electrode structure.

The invention relates to mesogenic media comprising a first component, component A, consisting of bimesogenic compounds selected from the group of compounds of formulae A-I to A-III ##STR00001## a second component, component B, consisting of nematogenic compounds, preferably selected from the group of compounds of formulae B-I to B-III ##STR00002## and a third component, component C, consisting of one or more chiral molecules, wherein the parameters have the meaning given in claim 1, to the use of mesogenic media in flexoelectric liquid crystal devices and to those devices comprising a liquid crystal medium according to the present invention.

A flexoelectric liquid crystal composition containing at least one kind of smectic liquid crystal compound, a chiral dopant, and a charge scavenger, and exhibiting photoconductivity.

The present invention relates to a process of preparing a light modulation element of the PS-ULH (polymer stabilised ULH) type, which allows to reduce the operational voltage and allows to improve the switching time of the light modulation element.

The present invention relates to a process of preparing a light modulation element of the PS-ULH (polymer stabilised ULH) type.

The invention relates to bimesogenic compounds of formula I ##STR00001##
wherein R.sup.11, R.sup.12, MG.sup.11, MG.sup.12, X.sup.11, X.sup.12 and Sp.sup.1 have the meaning given in claim 1, to the use of bimesogenic compounds of formula I in liquid crystal media and particular to flexoelectric liquid crystal devices comprising a liquid crystal medium according to the present invention.