Patent ID: 6915042

Claim:
Slanted Bragg grating optical fiber comprising: an optical fiber of longitudinal axis Z; a slanted Bragg grating, called first SBG, photowritten in said fiber and having refractive index modulations along said axis Z, of period Λ 1 , which are inclined at a writing angle α 1 with said normal planet: and a second slanted Bragg grating, called second SBG, photowritten in said fiber and having refractive index modulations along said axis Z, of period Λ 2 , which are inclined at a writing angle α 2 with respect to said normal plane and defining a plane called second writing plane forming an angle α 2 with said normal plane, wherein said periods Λ 1 and Λ 2 and said writing angles α 1 and α 2 are substantially identical, said writing angles being between 0.1° and 20°, and an angle θ 1 between said first and second writing planes, about said axis, called the rotation angle, is between 60° and 120°.