Thermooptic deflection and switching in glass

Abstract
New types of active optical device in glass such as deflectors and modulators/switches using the thermooptic effect originating from the temperature dependence of the refractive index are proposed and demonstrated. Thermally induced index changes for light deflection and switching are provided by applying an appropriate voltage to a small film heater deposited on the glass surface. Thermooptic waveguide switches fabricated by the ion-exchange technique successfully exhibited a switching speed of the order of 1 msec with 0.5-W driving electric power.