MODE-COUPLING AND EQUILIBRIUM MODE DISTRIBUTION CONDITIONS IN PLASTICOPTICAL FIBERS

The equilibrium mode distribution (EMD) condition is critical for opti cal fiber measurements. In this letter, we examine the achievement of EMD condition inside plastic optical fibers (POF's) under different la unch conditions. Our pulse broadening measurements of step-index (SI) POF's as a function of fiber length show that the EMD condition can re adily be achieved in an SI POF much shorter than in glass optical fibe rs. The observation of the EMD condition was also independently verifi ed using the far-field pattern technique.