Abstract: A liquid-crystalline medium based on a mixture of polar compounds, containing one or more compounds of the formula I in which R, Y1, Y2 and X have the meanings indicated in Claim 1.

Abstract: The invention relates to electrooptical light modulating elements, to electrooptical displays containing elements of this type, and to display systems, e.g. television screens and computer monitors, and to the modulating media used therein. The inventive light modulating elements contain a mesogenic modulating medium that exists in an optically isotropic phase when the light modulating elements are in operation and, in addition to having a good contrast, a low dependency on the viewing angle and very short switching times, they are particularly characterized by having relatively low driving voltages with a very low dependency on temperature. The inventive modulating media are characterized in that they contain a chiral constituent. They preferably also contain an achiral constituent. Especially preferred, the control media comprise a blue phase.

Abstract: The invention relates to a photostable liquid-crystalline medium comprising at least one compound of the formula I and at least one compound of the formula II and to the use thereof for electro-optical purposes, and to displays containing this medium.