Popis: |
The performance characteristics of any multimode fiber optic component, be it connector, coupler, multiplexer, or switch, are dependent on the modal intensity profile at the input of the device. It follows that any component that restructures the modal distribution from its input ports to its output ports can affect the overall system performance by modifying the operation of downstream parts. Specifically, commonly available multimode couplers are known to modify the input modal distribution as a result of the coupling mechanism; typically, the coupled fiber includes an overabundance of higher order modes while the straight through fiber suffers from a depletion of these higher order modes. The modal profiles of the coupler output ports can be actively monitored during the manufacturing process, thus allowing this information to be fed back to optimize the resulting device. The results of such measurements, which show the evolution of the coupling process during fabrication, will be presented and discussed. This capability raises questions concerning quality control measures, specifications, and the actual influence of a single component's capability on different systems' overall performance. |