Dear Members,
 i want to evaluate the thin film  refractive index and thickness at 1550
nm,(deposited over Side polished fiber half block ) any idea how it can be done.
 Right now i'm trying to measure these film parameters with Prism coupling
method at He-Ne wavelength, but how can i measure it at 1550 nm.
  Any help will be heartly appreciated.
regards
Aashish singh