A Miniature Fabry Perot Sensor for Twist/Rotation, Strain and Temperature Measurements Based on a Four-Core Fiber

In this article, a novel miniature Fabry-Perot twist/rotation sensor using a four core fiber and quadruple interferometer setup is presented and demonstrated. Detailed sensor modeling, analytical evaluation and test measurement assessment were conducted in this contribution. The sensor structure comprises a single lead-in multicore fiber, which has four eccentrically positioned cores, a special asymmetrical microstructure, and an inline semi-reflective mirror, all packed in a glass capillary housing. A four core fiber positioned in front of a special asymmetrical microstructure and the inline semi reflective mirror defines four Fabry-Perot interferometers. Rotation of the sensors’ asymmetrical microstructure around the axis of the in-line four core fibers´ modulates the path lengths of all four interferometers simultaneously. Proper processing of path length changes of all four interferometers allows for unambiguous and temperature independent determination of the sensor’s rotation angle.

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Miniature Twist/Rotation Fabry Perot Sensor Based on a Four-Core Fiber

Proceedings ◽

10.3390/proceedings2131091 ◽

2018 ◽

Vol 2 (13) ◽

pp. 1091

Author(s):

Vedran Budinski ◽

Denis Donlagic

Keyword(s):

Path Length ◽

Optical Path Length ◽

Optical Path ◽

Glass Capillary ◽

Rotation Sensor ◽

Reflective Mirror ◽

Fabry Perot ◽

The Individual ◽

Optical Paths ◽

Multicore Fiber

This paper presents a miniature Fabry Perot twist/rotation sensor. The presented sensor consists of a single lead-in multicore fiber, which has four eccentrically positioned cores, a special asymmetrical microstructure, similar to a truncated cylinder, and an inline semi reflective mirror, all packed in a glass capillary housing. The perpendicular cut lead-in multicore fiber and the inline semi reflective mirror form four Fabry-Perot cavities. The optical path length of each Fabry-Perot interferometer is defined by the distance between mirrors, refractive index and twist/rotation angle of the microstructure in relation to the core positions in the lead in multicore fiber. Optical paths of Fabry-Perot Interferometers are modulated by a structure’s twist/rotation, change of structure length, or change of temperature. Each of these parameters modulate the optical path length of the individual interferometers in their own separate fashion, thus allowing independent measurements of twist/rotation, length/strain and temperature.

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Problems in Thin-Film X-ray Quantification

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100135897 ◽

1990 ◽

Vol 48 (2) ◽

pp. 458-459

Author(s):

J N Chapman ◽

W A P Nicholson

Keyword(s):

Thin Film ◽

Specimen Thickness ◽

X Rays ◽

Characteristic Peak ◽

Local Composition ◽

X Ray ◽

Measured Ratio ◽

Path Lengths ◽

Composition Changes

Energy dispersive x-ray microanalysis (EDX) is widely used for the quantitative determination of local composition in thin film specimens. Extraction of quantitative data is usually accomplished by relating the ratio of the number of atoms of two species A and B in the volume excited by the electron beam (nA/nB) to the corresponding ratio of detected characteristic photons (NA/NB) through the use of a k-factor. This leads to an expression of the form nA/nB = kAB NA/NB where kAB is a measure of the relative efficiency with which x-rays are generated and detected from the two species.Errors in thin film x-ray quantification can arise from uncertainties in both NA/NB and kAB. In addition to the inevitable statistical errors, particularly severe problems arise in accurately determining the former if (i) mass loss occurs during spectrum acquisition so that the composition changes as irradiation proceeds, (ii) the characteristic peak from one of the minority components of interest is overlapped by the much larger peak from a majority component, (iii) the measured ratio varies significantly with specimen thickness as a result of electron channeling, or (iv) varying absorption corrections are required due to photons generated at different points having to traverse different path lengths through specimens of irregular and unknown topography on their way to the detector.

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Liquid level sensor based on dynamic Fabry–Perot interferometers in processed capillary fiber

Scientific Reports ◽

10.1038/s41598-021-82193-5 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Pablo Roldán-Varona ◽

Rosa Ana Pérez-Herrera ◽

Luis Rodríguez-Cobo ◽

Luis Reyes-González ◽

Manuel López-Amo ◽

...

Keyword(s):

Optical Fiber Sensor ◽

Liquid Level ◽

Hollow Core ◽

Immiscible Liquids ◽

Fabry Perot ◽

Detection Mode ◽

Level Sensor ◽

Core Fiber ◽

Liquid Level Sensor ◽

Silica Capillary

AbstractIn this work, a novel optical fiber sensor capable of measuring both the liquid level and its refractive index is designed, manufactured and demonstrated through simulations and experimentally. For this, a silica capillary hollow-core fiber is used. The fiber, with a sensing length of 1.55 mm, has been processed with a femtosecond laser, so that it incorporates four holes in its structure. In this way, the liquid enters the air core, and it is possible to perform the sensing through the Fabry–Perot cavities that the liquid generates. The detection mode is in reflection. With a resolution of 4 μm (liquid level), it is in the state of the art of this type of sensor. The system is designed so that in the future it will be capable of measuring the level of immiscible liquids, that is, liquids that form stratified layers. It can be useful to determine the presence of impurities in tanks.

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Determination of C1−C4 fatty acids as p-bromophenacyl esters using glass-capillary gas chromatography and electron-capture detection

Chromatographia ◽

10.1007/bf02290554 ◽

1983 ◽

Vol 17 (4) ◽

pp. 185-190 ◽

Cited By ~ 11

Author(s):

M. Larsson ◽

C. Roos

Keyword(s):

Fatty Acids ◽

Gas Chromatography ◽

Electron Capture ◽

Capillary Gas Chromatography ◽

Electron Capture Detection ◽

Glass Capillary

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Gas chromatographic determination of 5-alkyl-uracils and 5-alkyl-deoxyuridines using flash methylation and glass capillary columns

Journal of Chromatography A ◽

10.1016/s0021-9673(00)86386-4 ◽

1980 ◽

Vol 191 ◽

pp. 253-260 ◽

Cited By ~ 3

Author(s):

G. Garzó ◽

G. Alexander ◽

A. Till

Keyword(s):

Chromatographic Determination ◽

Capillary Columns ◽

Glass Capillary ◽

Glass Capillary Columns ◽

Flash Methylation

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Opto-Microfluidic Fabry-Perot Sensor with Extended Air Cavity and Enhanced Pressure Sensitivity

Micromachines ◽

10.3390/mi13010019 ◽

2021 ◽

Vol 13 (1) ◽

pp. 19

Author(s):

Pengfei Zhang ◽

Chao Wang ◽

Liuwei Wan ◽

Qianqian Zhang ◽

Zidan Gong ◽

...

Keyword(s):

Static Pressure ◽

Liquid Surface ◽

Microfluidic Channel ◽

Single Mode ◽

Pressure Sensitivity ◽

Air Cavity ◽

Surface Reflection ◽

Sensor Structure ◽

Fabry Perot ◽

Silica Capillary

An opto-microfluidic static pressure sensor based on a fiber Fabry-Perot Interferometer (FPI) with extended air cavity for enhancing the measuring sensitivity is proposed. The FPI is constructed in a microfluidic channel by the combination of the fixed fiber-end reflection and floating liquid surface reflection faces. A change of the aquatic pressure will cause a drift of the liquid surface and the pressure can be measured by detecting the shift of the FPI spectrum. Sensitivity of the sensor structure can be enhanced significantly by extending the air region of the FPI. The structure is manufactured by using a common single-mode optical fiber, and a silica capillary with the inner wall coated with a hydrophobic film. A sample with 3500 μm air cavity length has demonstrated the pressure sensitivity of about 32.4 μm/kPa, and the temperature cross-sensitivity of about 0.33 kPa/K.

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Determination of N-Nitrosodimethylamine in the Smoke of High-Nitrate Tobacco Cigarettes

Beiträge zur Tabakforschung International/Contributions to Tobacco Research ◽

10.2478/cttr-2013-0310 ◽

1973 ◽

Vol 7 (2) ◽

Author(s):

G.P. Morie ◽

C.H. Sloan

Keyword(s):

Capillary Column ◽

Glass Capillary Column ◽

Gas Chromatograph ◽

Ionization Detector ◽

Glass Capillary ◽

Flame Ionization ◽

Basic Solutions ◽

Poly Ethylene ◽

Gas Chromatographic Method

AbstractA gas chromatographic method was developed for the determination of N-nitrosodimethylamine (NDMA) in cigarette smoke. The NDMA in the smoke of 200 cigarettes was trapped in a solution of sodium hydroxide and separated from most of the smoke components by distillation from acidic and basic solutions. The aqueous solution was extracted for 8 hr. into ethyl ether in a Dean Stark apparatus. To concentrate the solution of NDMA, the ether was distilled until only 5 ml of the solution remained. An aliquot of this solution was analysed by means of a gas chromatograph equipped with a 200-ft. glass capillary column coated with Carbowax 20-M poly(ethylene glycoI). An alkali metal flame ionization detector with a selectivity of 10*/1 for nitrogen compounds to normal hydrocarbons was used. Small amounts (2 ng) of nitrosamines in the presence of large amounts of other compounds were easily detected. N-nitrosodimethylamine-C

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