Fiber optic sensors are typically used with expensive tunable lasers or optical spectrum analyzers for wavelength interrogation. We propose to replace the tunable laser by a broadband optical source incorporated with novel thin linewidth acousto-optic tunable filter. It utilizes optical beam expanders constituted by photonic crystal rows of air holes in LiNbO3 waveguide. A new design is numerically studied for a short structure (with 32 photonic crystal rows) by 2D FDTD method. Extrapolation of these results to larger structure sizes (about 1 cm) demonstrates the possibility to develop compact interrogators with 0.4 pm wavelength resolution and 40 nm tunable range around 1550 nm.
|Titolo:||Compact Interrogator for Fiber Optic Bragg Sensors Based on Acousto-Optic Filter Formed by Photonic Crystal Rows of Air Holes|
|Data di pubblicazione:||2011|
|Digital Object Identifier (DOI):||10.1364/OL.36.003756|
|Appare nelle tipologie:||1.1 Articolo in rivista|