Liquid crystal devices for fiber optical applications

Liquid Crystals (LCs) prove to be the basic material for various applications in Electronic Imaging and Displays as well as Optoelectronics. We will consider the following LC devices for fiber optical applications. 1. Fast reliable low power optical switches. At present LC switches show certain advantages in comparison with microelectromechanical (MEM) systems, commonly used for the same purpose, such as (i) fast switching time; (ii) low controlling voltages and power consumption; (iii) higher reliability and working time. We shall demonstrate the new possible configurations of the fast LC shutters for fiber-optical system, based on (i) STN-LCD cell and (ii) fast deformed-helix ferroelectric liquid crystal (DHF-FLC) mode. 2. Passive elements of fiber optical communication systems, such as optical filters, attenuators, equalizers, polarization controllers, phase emulators etc. The LC electrooptical modes, used for the purpose will include the light polarization rotation, voltage controllable diffraction and fast switching of LC refractive index. The software for optimization of the LC modulation characteristics is demonstrated. 3. Passive fiber optical elements based on Photonic Crystals (PCs) and Liquid Crystals (LCs). Photonic crystals are known to provide wavelength-dependent filters, beam splitters, mirror components. Filling of the interstices of the photonic crystal with the photo-aligned LC material and subjecting the LC to a varying electric field can produce a tunable photonic crystal element. A method for the formation of controllable PC/LC structures, based on multiple-redrawing technique, applied for different types of glass filled with photo-aligned LC is discussed.