3-DIMENSIONAL CHARACTERIZATION OF THE LIGHT-DISTRIBUTION FROM DIFFUSING CYLINDRICAL OPTICAL-FIBER TIPS

A rapid and sensitive technique for quantitatively examining the three -dimensional light distribution from optical-fiber diffusers for photo dynamic therapy applications was developed. We have used this system t o evaluate the longitudinal and azimuthal uniformity of the light outp ut from cylindrical diffusing tips and have determined a standard dete ctor configuration for assessing the optical quality of these diffuser s. As an example of the sensitivity and the accuracy of this method, t he effect of microbending of the fiber on the output intensity distrib ution, as well as the effect of the choice of laser used, was investig ated and was seen to have a significant impact on the uniformity of th ese diffusers.