Functional Optical Fiber Sensors Detecting Imperceptible Physical/Chemical Changes for Smart Batteries

The battery technology progress has been a contradictory process in which performance improvement and hidden risks coexist.Now the battery is still a“black box”,thus requiring a deep understanding of its internal state.The battery should“sense its internal physical/chemical conditions”,which puts strict requirements on embedded sensing parts.This paper summarizes the application of advanced optical fiber sensors in lithium-ion batteries and energy storage technologies that may be mass deployed,focuses on the insights of advanced optical fiber sensors into the processes of one-dimensional nano-micro-level battery material structural phase transition,electrolyte degradation,electrode-electrolyte interface dynamics to three-dimensional macro-safety evolution.The paper contributes to understanding how to use optical fiber sensors to achieve“real”and“embedded”monitoring.Through the inherent advantages of the advanced optical fiber sensor,it helps clarify the battery internal state and reaction mechanism,aiding in the establishment of more detailed models.These advancements can promote the development of smart batteries,with significant importance lying in essentially promoting the improvement of system consistency.Furthermore,with the help of smart batteries in the future,the importance of consistency can be weakened or even eliminated.The application of advanced optical fiber sensors helps comprehensively improve the battery quality,reliability,and life.

An Optical Fiber Sensor for Simultaneous Measurement of pO2 and pH

Whether in the monitoring of critically ill patients such as shock, respiratory failure, brain injury, or in major anesthesia surgeries, it is necessary to evaluate the patient’s pO2 and pH. An optical fiber sensor presented is capable of monitoring the presence of oxygen partial pressure (pO2) and pH in the real-time. The sensor is based on fluorescence sensing of polymer immobilized in the oxygen/pH-sensitive membranes and covalently attached to the optical fiber probe. The design of this sensor uses LED as light source, which is an excitation light source, inducing specific wavelengths of fluorescence on the oxygen/pH-sensitive membrane. The intensity and lifetime of fluorescence are related to the pO2 and pH. So the pO2 and pH can be measured by the relationship between the pO2/pH values and the intensity and lifetime of fluorescence. The signal conditioning system based on DSP and STM32 was used to store and process data, and display test values. The response of the sensor for pO2 and pH monitoring with nitrogen (N2) as a balancing gas in the laboratory was performed. Finally, the oxygen/pH sensing scheme presented in this work is intended for using in biological, medical and environmental applications.

Numerical simulation of a truncated cladding negative curvature fiber sensor based on the surface plasmon resonance effect

A refractive index(RI)sensor based on the surface plasmon resonance effect is proposed using a truncated cladding negative curvature fiber(TC-NCF).The influences of the TC-NCF structure parameters on the sensing performances are investigated and compared with the traditional NCF.The simulation results show that the proposed TC-NCF RI sensor has an ultra-wide detection range from 1.16 to 1.43.The maximum wavelength sensitivity reaches 12400 nm/RIU,and the corresponding R^(2)of the polynomial fitting equation is 0.9999.The maximum and minimum resolutions are 2.56×10^(-5)and 8.06×10^(-6),respectively.In addition,the maximum amplitude sensitivity can reach-379.1 RIU^(-1)when the RI is chosen as 1.43.The proposed TC-NCF RI sensor could be useful in biochemical medicine,environmental monitoring,and food safety.

Stress Sensing by an Optical Fiber Sensor: Method and Process for the Characterization of the Sensor Response Depending on Several Designs

In this paper we propose an analyzing of the response of a stress optical fiber sensor of which we proposed several design. We show that an optical fiber sensor with these designs can covenanting allow the measuring the force/stress applied to a mechanical structure or which it is linked, by optimizing the uses of appropriate materials for constituting the sensor support. The experiment that we introduce to validate our approach based in principles includes design with a support bearing a multimode optical fiber organized in such a way that the transmitted light is attenuated when the fiber-bending angle coming from stitching in holes of the support is modified by the effects of the force/stress applied to the optical fiber sensor realized in this way. The tests realized concern the most relevant parameters that define the performances of the stress sensor that we propose. We present the problems that we to solved for the optimization of the sensor for selecting the more efficient material for the optical fiber sensor support related to a relevant choice of optical fibers.

DISTRIBUTED OPTICAL FIBER SENSOR FOR LONG-DISTANCE OIL PIPELINE HEALTH

A fully distributed optical fiber sensor （DOFS） for monitoring long-distance oil pipeline health is proposed based on optical time domain reflectometry （OTDR）. A smart and sensitive optical fiber cable is installed along the pipeline acting as a sensor, The experiments show that the cable swells when exposed to oil and induced additional bending losses inside the fiber, and the optical attenuation of the fiber coated by a thin skin with periodical hardness is sensitive to deformation and vibration caused by oil leakage, tampering, or mechanical impact. The region where the additional attenuation occurred is detected and located by DOFS based on OTDR, the types of pipeline accidents are identified according to the characteristics of transmitted optical power received by an optical power meter, Another prototype of DOFS based on a forward traveling frequency-modulated continuous-wave （FMCW） is also proposed to monitor pipeline. The advantages and disadvantages of DOFSs based on OTDR and FMCW are discussed. The experiments show that DOFSs are capable of detecting and locating distant oil pipeline leakages and damages in real time with an estimated precision of ten meters over tens of kilometers.

Femtosecond laser fabrication of nanograting-based distributed fiber sensors for extreme environmental applications

The femtosecond laser has emerged as a powerful tool for micro-and nanoscale device fabrication. Through nonlinear ionization processes, nanometer-sized material modifications can be inscribed in transparent materials for device fabrication. This paper describes femtosecond precision inscription of nanograting in silica fiber cores to form both distributed and point fiber sensors for sensing applications in extreme environmental conditions. Through the use of scanning electron microscope imaging and laser processing optimization,high-temperature stable, Type II femtosecond laser modifications were continuously inscribed,point by point, with only an insertion loss at 1 d B m~(-1) or 0.001 d B per point sensor device.High-temperature performance of fiber sensors was tested at 1000℃, which showed a temperature fluctuation of ±5.5℃ over 5 days. The low laser-induced insertion loss in optical fibers enabled the fabrication of a 1.4 m, radiation-resilient distributed fiber sensor. The in-pile testing of the distributed fiber sensor further showed that fiber sensors can execute stable and distributed temperature measurements in extreme radiation environments. Overall, this paper demonstrates that femtosecond-laser-fabricated fiber sensors are suitable measurement devices for applications in extreme environments.

A Fluorescence Optical Fiber Sensor for Amrinon Using a New Oxazole Compound

A new oxazole compound, 1,4 bis(naphtho[1,2 d][1,3]oxazol 2 yl)benzene(BNOB) was synthesized and incorporated into a thin plasticized polymeric membrane for sensing Amrinon. The sensor exhibits a linear response to Amrinon in the range of 7 98×10 -7 —1 52×10 -4 mol/L at pH 3 28—4 04. The response mainly originates from the Primary Inner Filter Effect, which causes a decrease in the fluorescence intensity of the sensor membrane. The distinct advantages of the proposed sensor are of full reversibility, high sensitivity and selectivity as well as short response time(<1 min), indicating that the sensor can be used to monitor Amrinon in serum samples.

Enzymatic Determination of Glucose by Optical-Fiber Sensor Sequential Injection Renewable Surface Spectrophotometry

On the basis of oxidative decoloration of bromopyrogallol red （BPR） with H2O2, catalyzed by horseradish peroxidase（ HRP）, and the sequential injection renewable surface technique（ SI-RST）, a highly sensitive optical-fiber sensor spectrophotometric method for the enzymatic determination of hydrogen peroxide was proposed. By coupling with a glucose oxidase（GOD）-catalyzed reaction, the method was used to determine glucose in human serum. The considerations in system and flow cell design, and factors that influence the determination performance are discussed. With 100μL of sample loaded and 0. 6 mg of bead trapped, the linear response range from 5.0 × 10^-8 to 5.2 × 10^-6 mol/L BPR with a detection limit（3σ） of 2. 5 ×10 ^-8 mol/L BPR, and a precision of 1.1% RSD（ n = 11 ） and a throughput of a 80 samples per hour can be achieved. Under the conditions of a 8. 7 × 10^ -6 mol/L BPR substrate, 0. 04 unit/mL HRP, 600 s reaction time and a reaction temperature of 37℃, the linear response range for H2O2 was from 5.0 × 10^-8 to 7.0 × 10^-6 mol/L with a detection limit（3σ） of 1.0 × 10^-8 mol/L and a precision of 3.7% RSD （ n = 11 ）. The linear response range by coupling with a GOD-catalyzed reaction was from 1.0 × 10^-7 to 1.0 × 10^-5 mol/L. The method was directly applied to determine glucose in human serum. Glucose contents obtained by the proposed procedure were compared with those obtained by using the phenol-4-AAP method, the error was found to be less than 3%.

An Optical Fiber Sensor Probe Using a PMMA/CPR Coated Bent Optical Fiber as a Transducer for Monitoring Trace Ammonia

Ammonia sensors have broad spectrum of applications for industrial process control as well as for environ-mental monitoring. An optical fiber ammonia sensor probe has been developed by using a bent optical fiber having dual poly(methyl methacrylate) (PMMA)/chlorophenol red (CPR) coatings as a transducer. This sen-sor probe was tested for monitoring trace ammonia in gas samples using air as sample matrix. The reaction of ammonia with CPR causes a color change of the reagent, which was detected by using fiber optic evanes-cent wave absorption spectrometry as a sensing signal. By adopting a dual layer coating structure, the sensor probe has faster response compared to a sensor using a broadly accepted sensing reagent-immobilized poly-mer coating structure. The sensor developed in this work is sensitive, has a detection limit of 2.7 ppb NH3 in air, which is the most sensitive among the reported optical fiber ammonia sensors to the best knowledge of the authors. The sensor is also reversible and has a response time of 25 minutes. The features of high sensi-tivity, reversibility and reasonable response time make this sensor technique very attractive for air quality monitoring.

Loading Localization by Small-Diameter Optical Fiber Sensors

Structural health monitoring(SHM)in service has attracted increasing attention for years.Load localization on a structure is studied hereby.Two algorithms,i.e.,support vector machine(SVM)method and back propagation neural network(BPNN)algorithm,are proposed to identify the loading positions individually.The feasibility of the suggested methods is evaluated through an experimental program on a carbon fiber reinforced plastic laminate.The experimental tests involve in application of four optical fiber-based sensors for strain measurement at discrete points.The sensors are specially designed fiber Bragg grating(FBG)in small diameter.The small-diameter FBG sensors are arrayed in 2-D on the laminate surface.The testing results indicate that the loading position could be detected by the proposed method.Using SVM method,the 2-D FBG sensors can approximate the loading location with maximum error less than 14 mm.However,the maximum localization error could be limited to about 1 mm by applying the BPNN algorithm.It is mainly because the convergence conditions(mean square error)can be set in advance,while SVM cannot.

Dark Variants of Luminous Bacteria Whole Cell Bioluminescent Optical Fiber Sensor to Genotoxicants

A stable dark variant separated from photobacterium phosphoreum (A2) was fixed in agar-gel membrane and immobilized onto an exposed end of a fiber-optic linked with bioluminometer. The variant could emit a luminescent signal in the presence of genotoxic agents, such as Mitomycin C (MC). The performance of this whole-cell optical fiber sensor system was examined as a function of several parameters, including gel probe thickness, bacterial cell density, and diameter of the fiber-optic core and working temperature. An optimal response to a model genotoxicant, Mitomycin C, was achieved with agar-bacterial gel membrane: the thickness of gel membrane was about 5 mm; the cell density of bacteria in gel membrane was about 2.0×107 /ml; the diameter of fiber-optic core was 5.0 mm; the working temperature was 25 ℃. Under these optimized conditions, the response time was less than 10 h to Mitomycin C, with a lower detection threshold of 0.1 mg/L.

Multi-functional optical fiber sensor system based on a dense wavelength division multiplexer

We propose a novel and efficient multi-functional optical fiber sensor system based on a dense wavelength division multiplexer(DWDM).This system consists of an optical fiber temperature sensor, an optical fiber strain sensor, and a 48-channel DWDM.This system can monitor temperature and strain changes at the same time.The ranges of these two sensors are from-20℃ to 100℃ and from-1000 με to 2000 με, respectively.The sensitivities of the temperature sensor and strain sensor are 0.03572 nm/℃ and 0.03808 nm/N, respectively.With the aid of a broadband source and spectrometer,different kinds and ranges of parameters in the environment can be monitored by using suitable sensors.

Localization of Distributed Fiber Sensor Employing a Sub-Ring

A simple distributed optical fiber sensing system used to monitor vibration signal has an additional sub-loop eoupled with main ring by a 3 dB coupler. This paper compares three outputting interfered beams, each of them travels in the sub-ring 0, 1, 2 times, separately. Using the simultaneous equations produced by those three outputs, we find the relation between the interference lights and vibration signal＇s characteristics, such as frequency, amplitude and position. Through simplifying and calculating, the vibration position can be obtained finally.

A Dnal-Mode Bow Tie Optical Fiber Sensor for Measurement of Axial Strain

An optical fiber strain sensor utilizing the mode-mode interference of LP01x,andLR11x,modes in bow tie optical fibers is described.The heterodyne interference caused byfrequency modulation of laser diode（LD） with ramp injection current is used torealize the detection of linear phase.Experimental results show a resolution of about 2%of one fringe corresponding to a strain of 2.9με.m.

An Optical Fiber Sensor for Electrification Measurement in Power Transformers

Static electrification and partial discharges caused by oil flow in power transformers lead to many accidents. In this paper, an optical fiber sensor which can be directly mounted inside high voltage electric devices for electrification measurement in power transformers is introduced. Unlike the existing normal electrification measurement methods which only be used in static oil, the new one takes optical fiber as its probe and measures the electrification in flowing oil by detecting luminous flux, and is available for on line monitoring.

High sensitivity dual core photonic crystal fiber sensor for simultaneous detection of two samples

The optical control ability of photonic crystal fiber(PCF)is a distinctive property suitable for improving sensing and plasma performance.This article proposes a dual-core D-channel PCF sensor that can detect two samples simultaneously,which effectively solves the problems of coating difficulty and low wavelength sensitivity.The PCF has four layers of air holes,which dramatically reduces the optical fiber loss and is more conducive to the application of sensors in actual production.In addition,by introducing dual cores on the upper and lower sides of the central air hole,reducing the spacing between the core and the gold nanolayer,a stronger evanescent field can be generated in the cladding air hole.The optical fiber sensor can detect the refractive index of two samples simultaneously with a maximum sensitivity of 21300 nm/RIU.To the best of our knowledge,the sensitivity achieved in this work is the highest sensitivity with the dual sample synchronous detection sensors.The detection range of the refraction index is 1.35-1.41,and the resolution of the sensor is 4.695×10^(-6).Overall,the sensor will be suitable for medical detection,organic chemical sensing,analyte detection,and other fields.

Application Research of the Non-Destructive Testing Using Optical Fiber Sensor

In this paper, an optical fiber sensor is designed by using optical Faraday effect. It is composed of fiber collimator, polarizer, magneto-optical crystal and mirror. Based on the magnetic flux leakage (MFL) theory, The optical fiber sensor was placed between two permanent magnets with the N-pole. Therefore, the optical fiber sensing system was built to detect the defective ferromagnetic objects. Theoretical and experimental studies shown that the system can identify a little defects, such as irons’ blind hole (diameter φ =?3mm , depth t = 4mm?), irons’ grooves (length l= 30mm , width?ω = 10mm ), hole (φ?=?3mm ) and crackle etc. The system has the characteristics of small size, high sensitivity, fast signal response and high resolution. In terms of the defective oil and gas pipelines detection, The optical fiber sensing system is used in non-destructive testing, which will be valuable and meaningful.

A Dual-Parameter Fusion Distributed Optical Fiber Sensor System for Oil and Gas Pipeline Monitoring

For oil and gas pipeline monitoring applications, this paper proposed a dual-parameter fusion distributed fiber optic sensor system that enables distributed temperature and distributed vibration measurements in a single fiber. Through the fiber-scattering spectrum time domain detection combined with coded pulse sequence and Raman scattering spectrum is obtained, which realizes high-resolution temperature measurement and wide-band vibrational wave measurement. The experimental results show that, on 10 km optical fiber measurement, temperature resolution up to 0.1?C and vibration response frequency range 20 Hz - 5 kHz. This sensing system achieves temperature and vibration dual-parameter measurements with fiber optics, greatly simplifying the system and facilitating installation and it can be widely used in oil and gas pipeline monitoring.

Complete Phase-strain Model for Interferometric Optical Fiber Sensor

ＣｏｍｐｌｅｔｅＰｈａｓｅ－ｓｔｒａｉｎＭｏｄｅｌｆｏｒＩｎｔｅｒｆｅｒｏｍｅｔｒｉｃＯｐｔｉｃａｌＦｉｂｅｒＳｅｎｓｏｒ￥ＹＡＮＧＪｉａｎｌｉａｎｇ；ＸＩＡＮＧＱｉｎｇ；ＨＵＡＮＧＤｅｘｉｕ（ＨｕａｚｈｏｕｇＵｎｉｖｅｒｓｉｔｙｏｆＳｃｉｅｎｃｅａ...

NS推出WEBENCH Sensor Designer在线设计工具

美国国家半导体公司（National Semiconductor Corporation）宣布推出WEBENCH Sensor Designer，据称是业界首套用于开发传感器信号路径解决方案的在线设计工具。从构思、仿真测试以至建模的整个设计过程中，工程师都可以利用这套设计工具轻松高效地完成医疗、工业及高端电子消费产品等领域的传感器信号路径解决方案。