ABSTRACT
Integrated optics, which has been a research topic for about 20 years, deals with compact single function devices and the integration of multiple optical functionalities on a single chip or into a single package. Ultimately, this is seen as a way to reduce footprint and cost with respect to conventional bulk and micro-optic components, and also to obtain components with increased performance or even new functionalities. Planar optical waveguides are the keys for the construction of integrated optical circuits. One basic requirement for large-scale integration is that the overall device losses should be low, which in turn translates into an upper limit for the propagation losses through straight and curved waveguides. Functional devices often need a dynamic control of the properties of the guided mode, and depending on the application different physical phenomena are used. Waveguide couplers and power splitters are needed for the construction of interferometric devices.
