Broadband Cavity‐Mode Lasing from Dye‐Doped Nematic Liquid Crystals Sandwiched by Broadband Cholesteric Liquid Crystal Bragg Reflectors

Multiple polymer cholesteric liquid crystal (PCLC) layers with different pitches and a sandwich structure of nematic liquid crystal by these PCLC films are presented. The former serves as broadband-distributed Bragg reflectors and the latter as multiple-band electrotunable filters. Using the latter dye-doped hybrid film red–green–blue simultaneous lasing due to Fabry–Perot cavity modes is achieved (see figure).