Method of forming a grating in an optical waveguide

摘要

A method and apparatus for writing a Bragg grating in a photosensitive optical waveguide is disclosed. The novel method comprises an interferometer having precisely adjustable light collecting and directing components. A phase mask illuminated with ultraviolet light is used as the interferometer light source. The adjustability of the interferometer allows the writing of Bragg gratings for filtering wavelengths in the range 1275 nm to 1575 nm while adjusting the appropriate interferometer elements by only +/- 0.75 DEG each. <IMAGE>