A side-chain liquid crystalline polymer dispersed into an amorphous polymer matrix can be used as a thermo-optical device that exhibits scattering at low temperatures and becomes transparent when heated above the clearing temperature of the Liquid crystalline polymer. The blend of the side-chain liquid crystalline polymer and the UV-polymerizable monomer is yet two-phasic before polymerization and exhibits some additional phase separation during polymerization. Especially the thermal stability, but also the mechanical stability, of the thermo-optical device is considerably improved when dispersing a Liquid crystalline polymer instead of a low molar mass liquid crystal into a polymer matrix.