Novel tuneable on-fiber polymeric phase-mask for fiber and planar waveguide Bragg grating fabrication

UV transparent, on-fiber elastomeric phase-masks by casting directly on holographic glass phase-mask plates are demonstrated for the first time. These translation insensitive masks have been used to fabricate fiber Bragg gratings by simple exposure to 262 nm UV radiation. The stretchable phase-masks allow the Bragg wavelength of the inscribed grating to be changed easily. Multiple Bragg gratings at widely different wavelengths have been inscribed in one fiber using the same phase-mask. Inexpensive and disposable, the phase-masks allow the inscription of gratings in planar waveguides and fibers without causing contact-damage to either, and show the possibility of creating widely tuneable 1-D band-gap structures. In-situ fine tuning of the desired Bragg wavelength or correcting for errors in the phase-mask during inscription are other possible uses of this technology.