Abstract
Pitch vs. temperature dependences and selective transmission spectra are presented for several induced cholesteric systems formed by nematic liquid crystals doped by optically active L-menthol and tigogenin derivatives. The systems studied show improved colour—contrast characteristics with low Δλ0. as compared with the more common chiral nematic systems based on 2-methylbutyl substituted nematogens. Prospective applications of such systems are outlined.