Low absorption liquid crystals for mid-wave infrared applications.

A partially fluorinated terphenyl liquid crystal with low absorption in both mid-wave infrared (MWIR) and near IR regions is developed and its properties evaluated. This compound exhibits a nematic phase (although only about 2 °C), reasonably high birefringence (Δn~0.2), low visco-elastic coefficient, and modest dielectric anisotropy (Δε = -2.7). This compound serves as an important first example for future development of low-loss MWIR liquid crystals and devices.