What we believe to be a novel fiber-optical inclinometer based on a dual-path core-to-cladding mode coupling mechanism is demonstrated. Both the amplitude and tilt direction of bends about a 2-mm-long flexure joint in an optical fiber can be determined. The sensor head consists of a nonadiabatic abrupt taper cascaded with a weakly tilted fiber Bragg grating. Measured bend angles of up to 12° are demonstrated, as well as a method to increase the sensitivity for bend angles smaller than 4°.
© 2010 Optical Society of America
Fiber Optics and Optical Communications
Original Manuscript: January 7, 2010
Revised Manuscript: February 4, 2010
Manuscript Accepted: February 19, 2010
Published: March 31, 2010
Li-Yang Shao and Jacques Albert, "Compact fiber-optic vector inclinometer," Opt. Lett. 35, 1034-1036 (2010)