Multi-wavelength and bandwidth tunable liquid crystal filter

The chiral induced liquid crystals (LCs) can be widely used in filter devices due to the Bragg reflection. With templating technology, a single-layer structure multi-wavelength blue phase liquid crystal(BPLC) filters was investigated. By multiple liquid crystal refilling processes, LC filters with two and three reflection peaks was fabricated, and the reflection wavelength and bandwidth of the filters matched well with the design parameters. Meanwhile, the bandwidth tunable cholesteric liquid crystal(CLC) filter of single layer structure was investigated. By multiple refilling the CLCs of designed reflection peak into the CLC template, the broadband single-layer structure CLC filter can be achieved. The experimental results show that the maximum shift of the center wavelength is only 16 nm. Moreover, the bandwidth of the cholesteric liquid crystal can be broadened by 96% and can continue to expand. The manufacturing processes of the single-layer chiral spiral structure liquid crystal filter have good scalability and repeatability.