An optical fiber is tapered, preferably adiabatically, and has a material coated on it for chemical bonding with fluorophores. When the fluorophores couple with the material, evanescent radiation generated fibers causes the fluorophores to fluoresce, and the fluorescence is coupled back into the fib...http://www.google.ca/patents/US6558958?utm_source=gb-gplus-sharePatent US6558958 - Optical fiber evanescent field excited fluorosensor and method of manufacture
