Octahydro binaphthyl-based chiral compound-containing liquid-crystal composition and optical element

摘要

A liquid-crystal composition is composed of at least one chiral compound represented by general formula (K1) or (K2) and at least one achiral liquid-crystal component:; (wherein, in formulas (K1) and (K2), R^k1 is, for example, alkyl having 1 to 5 carbons, R^k2 is, for example, alkyl having 1 to 20 carbons, ring A^k1 is, for example, 1,4-phenylene, X^k1 is, for example, a single bond, Y^k1 is, for example, —(CH₂)_n—, n is an integer from 0 to 20, Z^k1 is, for example, a single bond, mk1 is, for example, an integer from 2 to 4, and nk1 and nk2 are, for example, an integer from 0 to 2).