A high-sensitivity liquid level sensor based on single-mode taper-thin core taper single-mode fiber structure

Abstract

An optical in-fiber Mach-Zehnder interferometer based on thin core fiber for liquid level sensing is proposed and experimentally demonstrated. The sensor head is composed of a single-mode taper-thin core taper single-mode fiber structure constructed via fusion splicing. The operational principle relies on the sensitivity of intermodal interference to liquid level variation ; this is achieved by employing tapers as couplers. Experimental results reveal that the transmission spectrum exhibits a linearly red-shift, with the liquid level changing from 0 to 15 mm, and achieves enhanced sensitivities of 0.6853 nm mm −1 , 0.9062 nm mm −1 , and 1.2416 nm mm −1 for liquid RIs of 1.3352, 1.3491, and 1.3698, respectively. A temperature assessment is conducted, which demonstrates that the maximum measurement error induced by temperature is −0.017 mm • C −1 , which indicates the sensor shows real potential for practical applications.

Ultrasensitive liquid level sensor based on slice-shaped composite long period fiber grating

“…SMF-taper-TCF-taper-SMF [23] 16 15 1241. 6 17 SMF-PCF-SMF with a bending cantilever setup [28] Not reported 8 111.27 (1.333 RI) Not reported SMF-PMF-SMF with waist enlarged fiber tapers [29] 35 28 279 2.21 SMF-PMF-SMF with waist enlarged fiber tapers [29] 40 28 186 Not reported SMF-MMF-TF-SMF with aligned spliced [30] 18 9 −175.8 (1.334 RI) 350 SMF-RCF-MMF-SMF with misaligned spliced [31] 300 120 6 6533…”

“…In the research of high-sensitivity liquid level measurement, some people proposed the MMF cascading hollow-core fiber (HCF) and FBG (SMF-MMF-HCF-SMF/FBG) with an aligned spliced structure [21] , surrounding RI (SRI)-based etched chirped FBG structure [22] , and MMF-HCF-FBG structure [23] . MMF has many modes and strong RI modulation ability, which can effectively shorten the grating length.…”

Hybridized Nanogenerators for Multifunctional Self-Powered Sensing: Principles, Prototypes, and Perspectives

“…In recent years, with the continuous development of electronic technology and automation, pneumatic flow and liquid level measurement have become increasingly prominent. The production of daily chemical products, marine engineering construction, and early warning of marine disasters cannot be separated from the monitoring of liquid level (Shao et al, 2020;Fu et al, 2020). For promoting the application of TENG in SPMS, Wang et al designed a magnetic flap-type multifunctional sensor system based on the triboelectric effect, which can be used to detect pneumatic flow and liquid level (Wang et al, 2020b).…”

A liquid lever sensor based on an abrupt taper and micro‐arc Michelson interferometer in single‐mode fiber

“…The experimental structure shows that the liquid level sensitivity of the sensor is −0.3163 nm/mm when the length of the sevencore fiber in this MZI is 16 mm. 13 Antonio-Lopez et al proposed a MI liquid level sensor based on multimode fiber (MMF), the structure of which is made by fusing a coreless optical fiber in the middle of two SMFs. The coreless optical fiber is used as the sensing fiber of this MI sensor to achieve the liquid level measurement.…”