Citation:
Edmon Chehura, Stephen W. James, and Ralph P. Tatam. A simple method for fabricating phase-shifted fibre Bragg gratings with flexible choice of centre wavelength. 20th International Conference on Optical Fibre Sensors, edited by Julian Jones, Brian Culshaw,
Wolfgang Ecke, José Miguel López-Higuera, Reinhardt Willsch, Proc. of SPIE Vol. 7503. pp 7503p1-4
Abstract:
A simple technique for fabricating phase-shifted fibre Bragg gratings (PSFBGs)
without the use of a phase-shifted phase mask is presented. Two, 3-mm long,
standard fibre Bragg gratings (FBGs) were inscribed sequentially in singlemode
fibre at the same Bragg wavelength such that the FBGs physically overlapped by
one grating period. This induces a spectral-hole in the middle of the reflection
spectrum of a standard FBG, equivalent to a π-phase shifted FBG. The flexibility
of the technique in writing PSFBGs at any choice of wavelength is demonstrated.
The results show that PSFBG devices produced by this method are highly
reproducible and the process is fast
