Power loss at directional change in dielectric waveguides.

Wave propagation in a single-mode dielectric waveguide that changes in direction is treated theoretically. The directional change is represented as a sequence of straight waveguide sections joined by sharp corners. Power is exchanged between guided and unguided modes at the corners. Numerical results for slab waveguides illustrate that the loss for either a gradual curve or a sequence of two or more corner bends oscillates as a function of the distance over which the directional change takes place.