Ultrasensitive vector bending sensor based on multicore optical fiber

Abstract

In this Letter, we demonstrate a compellingly simple directional bending sensor based on multicore optical fibers (MCF). The device operates in reflection mode and consists of a short segment of a three-core MCF that is fusion spliced at the distal end of a standard single mode optical fiber. The asymmetry of our MCF along with the high sensitivity of the supermodes of the MCF make the small bending on the MCF induce drastic changes in the supermodes, their excitation, and, consequently, on the reflected spectrum. Our MCF bending sensor was found to be highly sensitive (4094 pm/deg) to small bending angles. Moreover, it is capable of distinguishing multiple bending orientations.

Minimalist Approach for the Design of Microstructured Optical Fiber Sensors

“…This has an important impact on the sensor resolution. For the sensor reported in [32], for example, one can estimate a resolution limit of 0.01 m À1 , which is similar to the one we can find in our results (0.02 m À1 ).…”

“…It is worth saying, however, that greater sensitivity values can be attained in other configurations. For example, we find in the literature that fibers with two or three cores can provide sensitivities of hundreds of nanometers per inverse meter [32,33]. Nevertheless, the spectral features whose spectral shifts are considered in [32,33] are much broader than the Bragg peak in the surface-core fiber we measured.…”

Optimized active multicore fiber bending sensor

“…Minimum operational curvature radii, i.e. maximum losses, of demonstrated MCF bending sensors are in the range of tens of cm: 54 cm [7], 23 cm [8] and 19 cm [3]. Fig.…”

Fiber optic sensors based on strongly coupled multicore fiber

“…1. Very similar devices can be designed to measure temperature, strain, bending, and vibrations [10][11][12][13][14][15][16]. Fig.…”