High Optical Contrast Liquid Crystal Switch and Analogue Response Attenuator at 1550 nm

A novel mixture of low molar mass organosiloxane liquid crystals, with an optimum tilt angle of 22.5°, exhibits very good alignment. A liquid crystal binary intensity switch with a high, >; 60 dB, extinction ratio and an analogue response attenuator, with 54 dB of attenuation, suitable for telecommunication applications at λ = 1550 nm were constructed based on such a mixture. The switch and attenuator operate with fast rise times of ~ 10 μs and ~ 3.8 μs, respectively, at moderate electric fields of up to ±15 V μm-1.