Micro displacement sensing based on fused taper fiber coupler

A microfiber coupler was prepared based on the fused-taper technique to realize high-sensitivity measurement of displacement. After stripping the coating layer and cutting and welding the two single-mode fibers, they were placed on the tapering platform, and the fiber coupler was prepared under burning of a hydrogen flame. An experimental device for micro displacement measurement was built based on optical fiber coupling theory. In this study, the influence of different taper waist diameters on micro-displacement measurement was explored. Experimental results show that within a definite range of micro displacement measurement, the smaller waist diameter of the sensor indicates greater sensitivity. The interference spectrum displays a significant blue shift. The sensitivity of the microfiber coupler is 143.92 pm/μm. The experimental results verify that the microfiber taper coupler has high sensitivity in micro displacement measurement. The coupler can be used to develop and fabricate displacement sensors in the future.