scholarly journals Influence of environment temperature wide-range variation on Brillouin shift in optical fiber

2010 ◽  
Vol 59 (9) ◽  
pp. 6219
Author(s):  
Zhao Li-Juan
Keyword(s):  
Optical Fiber ◽  
Wide Range ◽  
Environment Temperature ◽  
Range Variation

scholarly journals Fiber Optic Attenuator

2021 ◽  
Vol 2086 (1) ◽  
pp. 012128
Author(s):  
D P Andreev ◽  
E I Andreeva
Keyword(s):  
Optical Fiber ◽  
Spectral Dependence ◽  
Fiber Optic ◽  
Dynamic Range ◽  
Wide Range ◽  
Bending Losses ◽  
Type Fiber

Abstract A study of a bending-type fiber-optic attenuator has been carried out. It is shown that the use of G.655 - optical fiber provides the largest dynamic range of the attenuator. The spectral dependence of the bending losses was measured in a wide range of wavelengths: from 1270 to 1610 nm.

Study on Coupling of Step and Graded Index Single Mode Optical Fiber Considering the Transverse Misalignment

2020 ◽  
Vol 8 (2) ◽  
pp. 78-82
Author(s):  
Prosenjit Roy Chowdhury ◽  
◽  
Keyword(s):  
Optical Fiber ◽  
Communication Systems ◽  
Structural Parameters ◽  
Fractional Power ◽  
Single Mode ◽  
Spot Size ◽  
Fiber Coupling ◽  
Fundamental Parameters ◽  
Graded Index ◽  
Wide Range

"Advance design and day to day up-gradation of communication system is the requirement of international telecommunication. The optical communication systems involve the effective fiber coupling or splicing to meet the need of long communication channel. When the studies on both the intensive and extensive properties of optical fiber are exploring new research horizons, the effectiveness of such systems can be calibrated with transmission parameters like transmitted fractional power, which is a function of ‘spot size’ as well. Our study of fiber junctions based on fundamental parameters like wavelength, fiber profile index etc. has touched some unrevealed areas and explored some interesting results. The profile index of optical fiber has received less attention compared to other structural parameters of optical fiber but our study at important wavelengths for different profiles has shown that the less-used fiber profiles has some interesting premier outcomes, which can introduce some significant impact on optical fiber based system design and engineering. We have observed almost frequency or wavelength independent transmitted fractional power around the most used 1.55 micrometer wavelengths at some rarely used fiber profile index. Our study predicts the best and worst fiber profiles for transmitted fractional power (T ), at the same time, we have observed the fiber profile index independent region for a band of ‘T’ values. The reporting and its approach are found to be premier in this field. So, our work is reporting a comparison of effective fiber-to-fiber coupling, based on fiber profile index of different fibers. It is also giving a clear view of the wavelength dependency of effective fiber coupling for different fibers having wide range of graded fiber profiles."

scholarly journals Carbon Allotrope-Based Optical Fibers for Environmental and Biological Sensing: A Review

Sensors ◽  
2020 ◽  
Vol 20 (7) ◽  
pp. 2046 ◽  
Author(s):  
Stephanie Hui Kit Yap ◽  
Kok Ken Chan ◽  
Swee Chuan Tjin ◽  
Ken-Tye Yong
Keyword(s):  
Optical Fiber ◽  
Optical Fibers ◽  
High Sensitivity ◽  
Optical Fiber Sensors ◽  
Functional Coating ◽  
Fiber Sensors ◽  
Carbon Allotrope ◽  
Carbon Allotropes ◽  
Sensing Technology ◽  
Wide Range

Recently, carbon allotropes have received tremendous research interest and paved a new avenue for optical fiber sensing technology. Carbon allotropes exhibit unique sensing properties such as large surface to volume ratios, biocompatibility, and they can serve as molecule enrichers. Meanwhile, optical fibers possess a high degree of surface modification versatility that enables the incorporation of carbon allotropes as the functional coating for a wide range of detection tasks. Moreover, the combination of carbon allotropes and optical fibers also yields high sensitivity and specificity to monitor target molecules in the vicinity of the nanocoating surface. In this review, the development of carbon allotropes-based optical fiber sensors is studied. The first section provides an overview of four different types of carbon allotropes, including carbon nanotubes, carbon dots, graphene, and nanodiamonds. The second section discusses the synthesis approaches used to prepare these carbon allotropes, followed by some deposition techniques to functionalize the surface of the optical fiber, and the associated sensing mechanisms. Numerous applications that have benefitted from carbon allotrope-based optical fiber sensors such as temperature, strain, volatile organic compounds and biosensing applications are reviewed and summarized. Finally, a concluding section highlighting the technological deficiencies, challenges, and suggestions to overcome them is presented.

Research on Monitoring Instrument of Environmental Condition

2012 ◽  
Vol 424-425 ◽  
pp. 1309-1312
Author(s):  
Jun Hao Niu ◽  
Zhi Jin Qiu ◽  
Cong Hu
Keyword(s):  
Humidity Sensor ◽  
Small Error ◽  
Environmental Condition ◽  
Monitoring Instrument ◽  
Wide Range ◽  
Environment Temperature ◽  
Temperature And Humidity ◽  
Reliable Performance ◽  
Alarm Message ◽  
Reference Clock

A monitoring instrument of environment condition is described in this paper, which uses the LPC2368 as the controller. The acquisition of environmental condition is realized by using SHT11, which is a digital temperature and humidity sensor. A DS1302 is used as the real time reference clock device, and the time message is displayed on the LCD together with the environment temperature and humidity. As if the temperature or humidity is beyond the setting range, the alarm light and sound will be switched on to inform the manager. At the same time, the alarm message could be sent out to other monitor center by RS485 interface. Experimental results show that the temperature and humidity monitor features small, reliable performance, small error, and be suitable to a wide range.

scholarly journals Measurement of Pulse Wave Signals and Blood Pressure by a Plastic Optical Fiber FBG Sensor

Sensors ◽  
2019 ◽  
Vol 19 (23) ◽  
pp. 5088 ◽  
Author(s):  
Yuki Haseda ◽  
Julien Bonefacino ◽  
Hwa-Yaw Tam ◽  
Shun Chino ◽  
Shouhei Koyama ◽  
...  
Keyword(s):  
Blood Pressure ◽  
Optical Fiber ◽  
Calibration Curve ◽  
Pulse Wave ◽  
Blood Pressure Measurement ◽  
Plastic Optical Fiber ◽  
Fbg Sensor ◽  
Wide Range ◽  
Silica Optical Fiber ◽  
Fbg Sensors

Fiber Bragg grating (FBG) sensors fabricated in silica optical fiber (Silica-FBG) have been used to measure the strain of human arteries as pulse wave signals. A variety of vital signs including blood pressure can be derived from these signals. However, silica optical fiber presents a safety risk because it is easily fractured. In this research, an FBG sensor fabricated in plastic optical fiber (POF-FBG) was employed to resolve this problem. Pulse wave signals were measured by POF-FBG and silica-FBG sensors for four subjects. After signal processing, a calibration curve was constructed by partial least squares regression, then blood pressure was calculated from the calibration curve. As a result, the POF-FBG sensor could measure the pulse wave signals with an signal to noise (SN) ratio at least eight times higher than the silica-FBG sensor. Further, the measured signals were substantially similar to those of an acceleration plethysmograph (APG). Blood pressure is measured with low error, but the POF-FBG APG correlation is distributed from 0.54 to 0.72, which is not as high as desired. Based on these results, pulse wave signals should be measured under a wide range of reference blood pressures to confirm the reliability of blood pressure measurement uses POF-FBG sensors.

scholarly journals Halogen Bonding in the Complexes of Brominated Electrophiles with Chloride Anions: From a Weak Supramolecular Interaction to a Covalent Br–Cl Bond

Crystals ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1075
Author(s):  
Cody Loy ◽  
Matthias Zeller ◽  
Sergiy V. Rosokha
Keyword(s):  
Bond Strength ◽  
Halogen Bond ◽  
Covalent Bond ◽  
Halogen Bonding ◽  
Halogen Bonds ◽  
Nucleophilic Reaction ◽  
X Ray ◽  
Wide Range ◽  
Judicious Choice ◽  
Range Variation

The wide-range variation of the strength of halogen bonds (XB) not only facilitates a variety of applications of this interaction, but it also allows examining the relation (and interconversion) between supramolecular and covalent bonding. Herein, the Br…Cl halogen bonding in a series of complexes of bromosubstituted electrophiles (R-Br) with chloride anions were examined via X-ray crystallographic and computational methods. Six co-crystals showing such bonding were prepared by evaporation of solutions of R-Br and tetra-n-propylammonium chloride or using Cl− anions released in the nucleophilic reaction of 1,4-diazabicyclo[2.2.2]octane with dichloromethane in the presence of R-Br. The co-crystal comprised networks formed by 3:3 or 2:2 halogen bonding between R-Br and Cl−, with the XB lengths varying from 3.0 Å to 3.25 Å. Analysis of the crystallographic database revealed examples of associations with substantially longer and shorter Br…Cl separations. DFT computations of an extended series of R–Br…Cl− complexes confirmed that the judicious choice of brominated electrophile allows varying halogen Br…Cl bond strength and length gradually from the values common for the weak intermolecular complexes to that approaching a fully developed covalent bond. This continuity of halogen bond strength in the experimental (solid-state) and calculated associations indicates a fundamental link between the covalent and supramolecular bonding.

scholarly journals Fiber Optic Gas Sensors Based on Lossy Mode Resonances and Sensing Materials Used Therefor: A Comprehensive Review

Sensors ◽  
2021 ◽  
Vol 21 (3) ◽  
pp. 731
Author(s):  
Ignacio Vitoria ◽  
Carlos Ruiz Zamarreño ◽  
Aritz Ozcariz ◽  
Ignacio R. Matias
Keyword(s):  
Optical Fiber ◽  
Gas Sensors ◽  
Gas Sensing ◽  
Optical Fiber Sensors ◽  
Industrial Sector ◽  
Fiber Sensors ◽  
Sensing Applications ◽  
Wide Range ◽  
Materials Used ◽  
Diagnostic Applications

Pollution in cities induces harmful effects on human health, which continuously increases the global demand of gas sensors for air quality control and monitoring. In the same manner, the industrial sector requests new gas sensors for their productive processes. Moreover, the association between exhaled gases and a wide range of diseases or health conditions opens the door for new diagnostic applications. The large number of applications for gas sensors has permitted the development of multiple sensing technologies. Among them, optical fiber gas sensors enable their utilization in remote locations, confined spaces or hostile environments as well as corrosive or explosive atmospheres. Particularly, Lossy Mode Resonance (LMR)-based optical fiber sensors employ the traditional metal oxides used for gas sensing purposes for the generation of the resonances. Some research has been conducted on the development of LMR-based optical fiber gas sensors; however, they have not been fully exploited yet and offer optimal possibilities for improvement. This review gives the reader a complete overview of the works focused on the utilization of LMR-based optical fiber sensors for gas sensing applications, summarizing the materials used for the development of these sensors as well as the fabrication procedures and the performance of these devices.

scholarly journals Theoretical and Experimental Study on Wide Range Optical Fiber Turbine Flow Sensor

Sensors ◽  
2016 ◽  
Vol 16 (7) ◽  
pp. 1095 ◽  
Author(s):  
Yuhuan Du ◽  
Yingqing Guo
Keyword(s):  
Experimental Study ◽  
Optical Fiber ◽  
Flow Sensor ◽  
Wide Range
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