MODES IN OPTICAL WAVE-GUIDES FORMED BY DIFFUSION REVISITED

For an optical waveguide with index of refractive having a small exponential variation superimposed on a constant background value, the wave equation can be solved exactly. It is shown that the characteristic equation determining the optical modes can be solved in an uncomplicated form. The number of normal modes depends on the waveguide properties through a simple equation. © 1994 American Institute of Physics.