Integrated optics using liquid crystals

This chapter shows how liquid crystals (LC) and their optical properties can be used to make reconfigurable optical waveguides, electro-optical and all-optical devices integrated on various substrate materials such as silicon, silicon nitride, polymers and glass. Chapter Contents: • 10.1 Optical properties of liquid crystals • 10.1.1 Optical anisotropy and refractive index • 10.1.2 Electro-optic effect in LC and molecular reorientation • 10.2 Switchable optical waveguides with liquid crystal core in silicon • 10.2.1 Fabrication technology • 10.2.2 Electro-optical and all-optical switching • 10.3 Photonic devices with liquid crystal core in polydimethylsiloxane • 10.3.1 Fabrication of LC:PDMS waveguides • 10.3.2 LC:PDMS-based photonic switches and demultiplexers • 10.4 Bragg reflectors based on liquid crystals • 10.4.1 Tuneable optical filters using composite gratings on glass • 10.4.1.1 Electro-optic filter • 10.4.1.2 All-optical filter • 10.4.2 Guided-wave tuneable Bragg gratings • 10.4.2.1 Coplanar electrode configuration • 10.4.2.2 Top-bottom electrode configuration • 10.5 Integrated optic devices based on a liquid crystal overlayer • 10.6 Conclusions • References.