BEND LOSS OF SLAB AND FIBER MODES COMPUTED WITH DIFFRACTION THEORY

Radiation losses of optical waveguides that are bent into a circle can be computed in a number of ways. In this paper we show that the bendi ng losses of fiber modes can be calculated with the help of Fraunhofer 's diffraction theory and test the validity of the result by showing t hat it is in agreement with the known bend loss formulas of the slab w aveguide and of the LP(01)-mode of the round step-index fiber. Like mo st efforts of this kind, the accuracy of our bend loss calculations is limited by the use of a scalar theory for approximating a vector prob lem and by additional mathematical approximations that are required to solve an integral.