Fast-response infrared phase modulator based on polymer network liquid crystal

We report a high birefringence terphenyl liquid crystal mixture, designated as M3, for infrared phase modulation with special emphasis on mid-wave infrared (MWIR). In addition to high birefringence, M3 exhibits excellent UV stability, modest dielectric anisotropy, and a very broad nematic range. The high birefringence enables a thin cell gap to be used for achieving a 2π phase change while maintaining a high transmittance (T>98%) in the MWIR region. To achieve fast response time, we employed a polymer network liquid crystal using M3 with 2π phase change at λ = 4μm and 3.6-ms response time. This response time is about 100X faster than that of a nematic LC phase modulator. ©2015 Optical Society of America OCIS codes: (120.5060) Phase modulation; (160.3710) Liquid crystals; (230.3720) Liquidcrystal devices. References and links 1. D.-K. Yang and S.-T. Wu, Fundamentals of Liquid Crystal Devices (John Wiley & Sons, 2006). 2. E. 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