organizzatore: prof. Stefan Wabnitz
Monday, December 9th 2019 – 10:30, DIET Lecture Room (SPV), 2nd floor
Transmission characteristics of multimode optical fibers depend strongly upon the mode-dependent attenuation, mode coupling and modal dispersion. It is necessary to have effective and accurate methods for calculating the influence of these effects on light transmission in optical fibers. Over the years, different approaches to simulate optical power transmission in multimode optical fibers have been used, including ray-tracing method, coupling-matrix method, the Fokker-Planck and the Langevin equation, and the power flow equation. Until recently, commercial simulation softwares either were designed specifically for single-mode optical fibers or modeled individual guided modes in multimode optical fibers with considerable detail, which is not adequate for multimode optical fibers with thousands or even millions of propagation modes, strong mode coupling and high variability. In this seminar, an approach which employs the power flow equation for investigation of transmission characteristics of multimode optical fibers with step-index, graded-index and W-index distribution will be presented. It will be shown that power flow equation can be successfully used in characterization of glass optical fibers, plastic optical fibers and plastic-clad silica fibers. Finally, the influence of bending, heating, twisting, and etching of multimode optical fiber on its transmission characteristics will be presented.