The analysis of logarithm fitting method for measuring decay time of optical fiber fluorescence sensors

Ce-doped LaBr3/AEBr2 (AE = Mg, Ca, Sr, Ba) eutectics were grown using the Bridgman–Stockbarger (BS) method in quartz ampoules. The eutectics (AE = Mg and Ca) showed optical transparency like optical fiber bundles. A grown Ce-doped LaBr3/MgBr2 eutectic shows a 355 nm emission ascribed to Ce3+ 4f-5d transition under X-ray excitation. The smaller the ionic size of AE, the higher the light yield of the sample was. The light yield of Ce:LaBr3/MgBr2 was 34,300 photon/MeV, which is higher than Ce:LYSO standard. Scintillation decay time under 662 keV gamma-ray excitation was 18.8 ns.

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Fluorescence decay-time characteristics of erbium-doped optical fiber at elevated temperatures

Review of Scientific Instruments ◽

10.1063/1.1148192 ◽

1997 ◽

Vol 68 (7) ◽

pp. 2764-2766 ◽

Cited By ~ 32

Author(s):

Z. Y. Zhang ◽

K. T. V. Grattan ◽

A. W. Palmer ◽

B. T. Meggitt ◽

T. Sun

Keyword(s):

Optical Fiber ◽

Decay Time ◽

Elevated Temperatures ◽

Fluorescence Decay ◽

Erbium Doped ◽

Fluorescence Decay Time

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Cubic fitting method of wavelength shift of optical fiber grating temperature sensor and a temperature measuring device

Journal of Physics Conference Series ◽

10.1088/1742-6596/1213/5/052082 ◽

2019 ◽

Vol 1213 ◽

pp. 052082

Author(s):

Wang Chengyou ◽

Deng Yajun ◽

Wei Peng ◽

Xue Haijun

Keyword(s):

Optical Fiber ◽

Temperature Sensor ◽

Wavelength Shift ◽

Fiber Grating ◽

Measuring Device ◽

Temperature Measuring ◽

Fitting Method

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Research for On-Line Measurement of Optical Fiber Diameter Based on Machine Vision

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.433-440.6497 ◽

2012 ◽

Vol 433-440 ◽

pp. 6497-6502 ◽

Cited By ~ 1

Author(s):

Yuan Yang ◽

Tao Geng ◽

Peng Li ◽

Wen Lei Yang

Keyword(s):

Machine Vision ◽

Optical Fiber ◽

Real Time ◽

Fiber Diameter ◽

Fitting Method ◽

Pixel Location ◽

On Line ◽

Image Edge ◽

High Level ◽

Geometry Parameter

Special optical fiber (D-type optical fiber) geometry parameter directly effect its sensing characteristics, it is very important to measure optical fiber diameter. But the present methods of measuring optical fiber diameter have some disadvantages, such as demanding high level environment and not real-time on-line measuring. This paper describes a method by applying machine vision technology to measure optical fiber diameter in real-time on-line. Firstly, Automatic Focusing System can collect clear fiber image by applying CMOS camera. Secondly, image edge was detected by using edge detector. And the precise location of image was detected by sub-pixel location technology based on gray moments. Lastly, optical fiber diameter is calculated by applying the two priority methods-least beeline fitting method. Experimental results show that the accuracy of measuring fiber diameter system is 1μm, and meet the requirements of real-time on-line measuring.

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New capillary optical fiber structure for fluorescence sensors

10.1117/12.229944 ◽

1996 ◽

Cited By ~ 1

Author(s):

Pauli Kiiveri ◽

Ari P. Hokkanen ◽

Raija Kylmanen ◽

Kari Keinanen ◽

Simo K. T. Tammela

Keyword(s):

Optical Fiber ◽

Fiber Structure ◽

Fluorescence Sensors

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Application of the Least Squares Fitting in Mine Optical Fiber Carbon Dioxide Monitoring System

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.278-280.983 ◽

2013 ◽

Vol 278-280 ◽

pp. 983-987 ◽

Cited By ~ 1

Author(s):

Ting Ting Zhang ◽

Xin Wang ◽

Yu Bin Wei ◽

Chang Wang ◽

Tong Yu Liu

Keyword(s):

Carbon Dioxide ◽

Optical Fiber ◽

Least Squares ◽

Monitoring System ◽

Coal Mine ◽

Tunable Diode Laser ◽

Detection Accuracy ◽

Minimum Detectable Concentration ◽

Least Squares Fitting ◽

Fitting Method

Carbon dioxide is one of the important signature gases in spontaneous combustion forecasting of coal goaf area. In the mine limited ventilation environment, concentration of CO2 directly affects the health of coal mines. So a new application of the least squares fitting method in Coal Mine gas monitoring was introduced. The optical fiber CO2 monitoring system which based on this method and tunable diode laser absorption spectroscopy (TDLAS) technology was used in Coal Mine beam tube system, and selected a near-infrared wavelength 1609.117nm fiber-coupled distributed feedback laser (DFB) as light source. Goaf area gas concentrations were directly calculated by the least squares fitting method which also simplified the calibration operation that used only one point to calibrate. Compared to electronic CO2 detector, this improved system has very high detection accuracy and stability. In the condition of 1.4m gas cell, the minimum detectable concentration is 0.05%, and the minimum detectable spectral absorption rate can up to , response time≤60s.

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