A liquid-crystalline medium, in particular based on a mixture of polar compounds, having compounds of formulae Y, CY, PY and/or LY, and compounds of formula S1 and/or S2:

##STR00001##

The present invention provides a liquid crystal composition comprising: at least one compound of general Formula I; at least one compound of general Formula II; at least one compound of general Formula M and at least one compound of general Formula N. The present invention also provides a liquid crystal display device comprising the liquid crystal composition. The liquid crystal composition provided in the present invention has a higher optical anisotropy, a higher clearing point, a higher dielectric anisotropy, a high transmittance and a larger average elastic constant. When the liquid crystal composition is used in the IPS liquid crystal display device, the transmittance of the display device can be effectively improved, so that the display device has a good display performance while also having good energy-saving and environment-friendly characteristics. ##STR00001## ##STR00002## ##STR00003## ##STR00004##

The present invention provides a liquid crystal composition comprising: at least one compound of general Formula I; at least one compound of general Formula II; at least one compound of general Formula M and at least one compound of general Formula N. The present invention also provides a liquid crystal display device comprising the liquid crystal composition. The liquid crystal composition provided in the present invention has a higher optical anisotropy, a higher clearing point, a higher dielectric anisotropy, a high transmittance and a larger average elastic constant. When the liquid crystal composition is used in the IPS liquid crystal display device, the transmittance of the display device can be effectively improved, so that the display device has a good display performance while also having good energy-saving and environment-friendly characteristics.

##STR00001##

A liquid-crystal composition and a liquid-crystal display device employing the liquid-crystal composition are provided. The liquid-crystal composition includes a first component and a second component. The first component includes one or more compounds represented by Formula (I), and the second component includes one or more compounds represented by Formula (II):

##STR00001## wherein R1, R2, A1, A2, A3, A4, Z1, Z2, Z3, m, m, n, and n are defined as in the specification.

A liquid-crystalline medium, in particular based on a mixture of polar compounds, having compounds of formulae Y, CY, PY and/or LY, and compounds of formula S1 and/or S2: ##STR00001##