Strain, temperature, moisture, and transverse force sensing using fused polymer optical fibers

Advanced Photonics Research

Díaz

Frizera

et al. 2020

Self Cite

Fiber‐optic sensing is resistant to electromagnetic interference; therefore, electromagnetic field sensing using fiber‐optic sensors is challenging. Herein, the first demonstration of fiber‐optic intrinsic electromagnetic field sensing based on modal interferometry with the highest reported sensitivity is presented (here, to be intrinsic means that the magnetic field interaction occurs only within the optical fiber, where there is no use of magnetic fluids or extrinsic structures). A fused polymer optical fiber (POF) is connected to two silica single‐mode fibers (SMFs) through an UV‐curing resin. Another interferometer with a nonfused POF is also fabricated, and the transmitted spectra of both the interferometers are compared in the presence of an electromagnetic field (0–240 mT). The results show the insensitivity of the nonfused POF interferometer and a mean sensitivity of 16.7 pm mT−1 for the fused POF interferometer, which presents a tenfold increase by changing the fused POF length from 2 to 5 cm, resulting in a sensitivity of 113.5 pm mT−1. The proposed intrinsic electromagnetic field sensor has the potential of measuring magnetic field intensities as low as 45 μT (considering its high sensitivity) with possibility of further increase with small changes in the signal acquisition components.

Section: Introductionmentioning

confidence: 99%

Highly Sensitive Fiber‐Optic Intrinsic Electromagnetic Field Sensing

Advanced Photonics Research

Díaz

Frizera

et al. 2020

Self Cite

“…The optical power of the transmitted light was converted into an electrical signal using a photodiode (IF‐D91, Industrial Fiber Optics) with a transimpedance amplifier. [ 39 ]…”

Section: Sensing Applications Of Fused Pofsmentioning

confidence: 99%

Sensing Applications of Polymer Optical Fiber Fuse

Advanced Photonics Research

Marques

Lee

et al. 2021

Self Cite

This article presents a review of the fuse effect in polymer optical fibers (POFs) and its sensing applications. First, the propagation mechanisms and the characteristics of the POF fuse are discussed, showing that its optical threshold power and propagation velocity are much lower than those of silica fiber fuse. In addition, it is shown that the main unique advantages of the POF fuse are its capability of transmitting optical signal as well as the electrical conductivity of the carbonized oscillatory path created in the fiber core. The physical properties of the fused POF are also described, such as its higher elasticity and stability to external effects. Subsequently, some applications of fused POFs are reviewed, such as temperature, strain, force, and angle sensors with higher sensitivity and stabler operation than those of nonfused POF‐based sensors. Finally, future perspectives on fused POF‐based sensing are discussed, where the magnetic field sensitivity plays an important role in implementing the optical devices. Thus, the unique features of fused POFs can provide a new paradigm for the fuse effect in optical fibers, in which the effect can be intentionally ignited for fabrication of novel in‐fiber devices and sensors with extended capabilities.

“…In addition, viscoelastic materials have a variation of their Young’s modulus in response to different parameters such as strain cycle frequency, temperature, and relative humidity [129]. Therefore, it is necessary to understand and characterize the POF viscoelastic response to propose a compensation of the viscoelastic effects and obtain a more reliable measurement of any POF sensor based on direct stress or strain on the fiber (such as curvature sensor [130], strain [131], and force [61] sensors) prior to their applications in healthcare devices and movement analysis.…”

Section: Polymer Optical Fiber Sensors: An Overviewmentioning

confidence: 99%

Polymer Optical Fiber Sensors in Healthcare Applications: A Comprehensive Review

Díaz

Avellar

et al. 2019

Sensors

Self Cite

170

Advances in medicine and improvements in life quality has led to an increase in the life expectancy of the general population. An ageing world population have placed demands on the use of assistive technology and, in particular, towards novel healthcare devices and sensors. Besides the electromagnetic field immunity, polymer optical fiber (POF) sensors have additional advantages due to their material features such as high flexibility, lower Young’s modulus (enabling high sensitivity for mechanical parameters), higher elastic limits, and impact resistance. Such advantages are well-aligned with the instrumentation requirements of many healthcare devices and in movement analysis. Aiming at these advantages, this review paper presents the state-of-the-art developments of POF sensors for healthcare applications. A plethora of healthcare applications are discussed, which include movement analysis, physiological parameters monitoring, instrumented insoles, as well as instrumentation of healthcare robotic devices such as exoskeletons, smart walkers, actuators, prostheses, and orthosis. This review paper shows the feasibility of using POF sensors in healthcare applications and, due to the aforementioned advantages, it is possible to envisage a further widespread use of such sensors in this research field in the next few years.