Described is a liquid crystal composition which satisfies at least one of such characteristics as high upper limit temperature of the nematic phase, low lower limit temperature of the nematic phase, low viscosity, adequate optical anisotropy, large negative dielectric anisotropy, high resistivity, high stability to ultraviolet light and high stability to heat, or which has an adequate balance between at least two of the above-mentioned characteristics. Also described is an AM element having a short response time, high voltage holding ratio, high contrast ratio, long life and the like. The liquid crystal composition contains a specific compound having a large negative dielectric anisotropy and a low lower limit temperature as a first component, a specific compound having a low viscosity or a high upper limit temperature as a second component, and a specific compound having a polymerizable group as a third component. The AM element contains the composition.

The present invention provides a birefringent lens material for a stereoscopic image display, the birefringent lens material containing two or more liquid crystal compounds each having at least one polymerizable functional group, a birefringent lens for a stereoscopic image display, the birefringent lens being formed by using the lens material, and a method for producing a birefringent lens for a stereoscopic image display using the lens material. The birefringent lens material for a stereoscopic image display and the birefringent lens for a stereoscopic image display of the present invention are good in terms of optical characteristics, durability, and productivity, in particular, productivity. The method for producing a birefringent lens for a stereoscopic image display of the present invention has good productivity.

Provided are a reactive mesogen that may improve display quality of a liquid crystal display, and a liquid crystal composition including the same. The reactive mesogen is represented by the following Formula:

##STR00001## where A.sub.1, A.sub.2, and A.sub.3 are each independently a substituted or unsubstituted divalent hydrocarbon ring, or a substituted or unsubstituted divalent heterocycle, L.sub.1 and L.sub.2 are each independently a direct linkage, O, S, CO, COO, OCOO, O(CH.sub.2).sub.k1, S(CH.sub.2).sub.k1, O(CF.sub.2).sub.k1, S(CF.sub.2).sub.k1, (CH.sub.2).sub.k1, CF.sub.2CH.sub.2, (CF.sub.2).sub.k1, CHCH, CFCF, CC, CHCHCOO, or (CH.sub.2).sub.k1COO(CH.sub.2).sub.k2O, Z.sub.1 and Z.sub.2 are each independently a direct linkage, O, S, CO, COO, OCOO, O(CH.sub.2).sub.m1, S(CH.sub.2).sub.m1, O(CF.sub.2).sub.m1, S(CF.sub.2).sub.m1, (CH.sub.2).sub.m1, CF.sub.2CH.sub.2, (CF.sub.2).sub.m1, CHCH, CFCF, CC, CHCHCOO, (CH.sub.2).sub.m1COO, (CH.sub.2).sub.m1COO(CH.sub.2).sub.m2O, CH(S.sub.pPa), CH.sub.2CH(S.sub.pPa), or (CH(S.sub.pPa)CH(S.sub.pPa)), Pa is a polymerizable group, B is an unsubstituted heterocycle, a substituted or unsubstituted crown ether group, or

##STR00002##

wherein T.sub.1 and T.sub.2 are each independently OH, CH.sub.3, CF.sub.3, CHF.sub.2, CH.sub.2F, CH.sub.2Br, CHBr.sub.2, CHCl.sub.2, or CH.sub.2Cl.

A compound represented by formula (1-1) or (1-2) is provided. ##STR00001##
For example, R.sup.1 and R.sup.2 are independently hydrogen, alkyl having 1 to 10 carbons or alkoxy having 1 to 9 carbons; the ring A.sup.1, the ring A.sup.2, the ring A.sup.3, the ring A.sup.4, the ring A.sup.5 and the ring A.sup.6 are independently 1,4-cyclohexylene or 1,4-phenylene; a, b, c, d, e and f are independently 0 or 1, and the sum of a, b, c, d, e and f is 2; and g, h, i, j, k and l are independently 0 or 1, and the sum of g, h, i, j, k and l is 2.

The present invention relates to liquid-crystalline media comprising at least one compound of the formula I and at least one compound of the formula II
or at least one compound of the formula I and at least one compound of the formula III
or at least one compound of the formula II and at least one compound of the formula III
or at least one compound of the formula I and at least one compound of the formula II and at least one compound of the formula III: ##STR00001##
in which the parameters have the meaning indicated in Claim 1, and to components comprising these media for high-frequency technology, in particular phase shifters and microwave array antennas.

There is provided a method for producing a birefringent lens for a stereoscopic image display using a birefringent material having two or more liquid crystal compounds each having at least one polymerizable functional group. The method includes the steps of providing the birefringent lens material; applying the birefringent lens material onto an alignment layer that has been subjected to an alignment treatment in a uniaxial direction, and forming the coating film into a lens shape by conducting curing with ultraviolet light.