An optical device includes a waveguide bounded by a region containing a photonic
band gap the properties of which determined the transfer characteristic of the
waveguide. Such a device may serve as a component of, for example a wavelength
division multiplexer, a monochromatic laser or a chemical sensor. It may serve
as an optical bus for an electronic component such as a microprocessor. These devices
are particularly suitable for incorporation in optical and opto-electronic intergrated
circuits as they permit the fabrication of waveguides having right-angle bends
with a radius of the order of 2 m.
