Multimode optical fibers: interplay of absorption and radiation losses.

We present results for power transmitted when a typical multimode optical fiber is excited by a Lamber-tian source. Power attenuation is due to absorbing core and cladding materials and radiation loss due to reflections from the circular cross section. Radiation loss is responsible for a significant power reduction (20-25% for Lambertian source) over distances much less than those for which material absorption is important.