Waltermann, C.C.WaltermannDoering, A.A.DoeringKöhring, M.M.KöhringAngelmahr, M.M.AngelmahrSchade, W.W.Schade2022-03-052022-03-052015https://publica.fraunhofer.de/handle/publica/24168510.1364/OL.40.0031092-s2.0-84942882378Femtosecond laser pulses were used for the direct point-by-point inscription of waveguides into the cladding of standard single-mode fibers. Homogeneous S-shaped waveguides have been processed as a bundle of overlapping lines without damaging the surrounding material. Within these structures, FBGs have been successfully inscribed and characterized. A sensor device to measure the bending direction of a fiber was created by two perpendicular inscribed cladding waveguides with FBG. Finally, a complete 3D shape sensor consisting of several bending sensor planes, capable of detecting bending radii even below 2.5 cm is demonstrated.en535journal article