In recent years, tilted fiber Bragg gratings (TFBGs) have been demonstrated to be a promising technological platform for sensing applications such as the measurement of axial strain, bending, vibration, and refractive index. However, complex spectral measurements combined with the difficulty of using TFBGs in a quasi-distributed sensors network limit the practical exploitation of this assessed technology. To address this issue, we propose a hybrid configuration involving uniform and TFBGs working in reflection, which makes the demodulation technique easier and allows multipoint sensing. This configuration provides a narrowband reflection signal that is modulated by the wavelength selective losses associated with some TFBG’s cladding-modes resonances. We report here the operating principle of the proposed device. An experimental validation is presented for refractive-index sensing purposes.
© 2009 Optical Society of America
Fiber Optics and Optical Communications
Original Manuscript: January 12, 2009
Revised Manuscript: March 24, 2009
Manuscript Accepted: May 8, 2009
Published: July 2, 2009
Christophe Caucheteur, Patrice Mégret, and Andrea Cusano, "Tilted Bragg grating multipoint sensor based on wavelength-gated cladding-modes coupling," Appl. Opt. 48, 3915-3920 (2009)