@inproceedings{shangguan93a,
  author = {H. Shangguan and T. W. Haw and K. W. Gregory and Lee W. Casperson},
  title = {Novel cylindrical illuminator tip for ultraviolet light delivery},
  booktitle = {SPIE Proceedings of Diagnostics and Therapeutic Cardiovascular Interventions III},
  editor = {G. S. Abela},
  year = {1993},
  volume = {1878},
  pages = {167--182},
  abstract = {The design, processing, and sequential testing of a novel cylindrical diffusing optical fiber tip for ultraviolet light delivery is described. This device has been shown to uniformly ($\pm$15\%) illuminate angioplasty balloons, 20\,mm in length, that are used in an experimental photochemotherapeutic treatment of swine intimal hyperplasia. Our experiments show that uniform diffusing tips of $<400\,\mu$m diameter can be reliably constructed for this and other interstitial applications. Modeling results indicate that this design is scalable to smaller diameters. The diffusing tips are made by stripping the protective buffer and etching away the cladding over a length of 20\,mm from the fiber tip and replacing it with a thin layer of optical epoxy mixed with Al$_2$O$_3$ powder. To improve the uniformity and ease of fabrication, we have evaluated a new device configuration where the tip is etched into a modified conical shape, and the distal end face is polished and then coated with an optically opaque epoxy. This is shown to uniformly scatter approximately 70\% of the light launched into the fiber without forward transmission.},
}