Fabrication of a Multifiber Optical Inclinometer

A new approach to multidimensional sensing is proposed, utilizing the individual fibers assembled along their length to form a multifiber bundle. The device allows for easy access to the individual fibers while offering similar properties to multicore optical fiber. To demonstrate, a two-axis inclinometer is rapidly developed and evaluated for its performance. In this example, three fibers containing fiber Bragg gratings written in single-mode fiber are metalized and attached to each other using a low-temperature indium-based solder. Using interferometric demodulation, an average inclination error of ±0.25° is obtained (at constant temperature) during each measurement cycle.