Listar por tema "Optical fiber sensors"
Mostrando ítems 21-40 de 42
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Monitoring of water freeze-thaw cycle by means of an etched single-mode - multimode - single-mode fiber-optic refractometer
As an alternative to the different technologies that permit the detection of in-situ ice formation on different surfaces, this contribution proposes the design of an etched single-mode – multimode – single-mode (E-SMS) ... -
Multichannel refractometer based on lossy mode resonances
In this work a new multiparameter sensor platform based on lossy mode resonances is presented. The structure consists of a soda-lime optical slab waveguide butt-coupled to multimode optical fibers. A variable thickness ... -
Multiparameter sensor based on a multiinterferometric serial configuration for temperature and strain measurements
In this work, a multi-parameter point sensor based on the combination of Fabry-Perot (FP) and the anti-resonant (AR) reflecting guidance in cascade configuration is proposed and experimentally demonstrated. This structure, ... -
Nanodeposition of materials with complex refractive index in long period fiber gratings
An overlay of higher refractive index than the cladding is deposited on a Long Period Fiber Grating (LPFG). This permits to improve in a great manner the sensitivity of the device to ambient and overlay refractive index ... -
Nanofabrication of phase-shifted Bragg gratings on the end facet of multimode fiber towards development of optical filters and sensors
This work describes the process of nanofabrication of phase-shifted Bragg gratings on the end facet of a multimode optical fiber with a pulsed DC sputtering system based on a single target. Several structures have been ... -
Optical fiber sensors based on nanoparticle-embedded coatings
The use of nanoparticles (NPs) in scientific applications has attracted the attention of many researchers in the last few years. The use of NPs can help researchers to tune the physical characteristics of the sensing coating ... -
Optical fiber sensors based on nanostructured materials for environmental applications
La contaminación ambiental es la presencia de agentes físicos, químicos o biológicos presentes en el agua, suelo y aire; siendo perjudiciales para la salud de las personas, así como para la vida vegetal y animal. Las ... -
Optical power-based interrogation of plasmonic tilted fiber Bragg grating biosensors
Two interrogation techniques for plasmonic tilted fiber Bragg grating sensors are reported and experimentally tested. Typical interrogation methods are usually based on tracking the wavelength shift of the most sensitive ... -
Optimización de dispositivos en fibra óptica basados en resonancias de modos con pérdidas para aplicaciones en biosensores
El desarrollo de los sensores en fibra óptica combinado con el avance de la nanotecnología ha proporcionado una excelente oportunidad para el desarrollo de nuevas plataformas sensoras ópticas portátiles, ligeras y de alto ... -
An optimized method based on digitalized Lissajous curve to determine lifetime of luminescent materials on optical fiber sensors
A method is proposed to determine lifetime of luminescent emissions based on the phase shift measurement employing the digitalized Lissajous representation: this diagram has been typically used with analogical algorithms, ... -
Overcoming non-local effects and Brillouin threshold limitations in Brillouin optical time domain sensors
We demonstrate, for the first time to our knowledge, a Brillouin optical time domain analysis (BOTDA) sensor that is able to operate with a probe power larger than the Brillouin threshold of the deployed sensing fiber ... -
Polarization diversity scheme for BOTDA sensors based on a double orthogonal pump interaction
We introduce a Brillouin optical time domain analysis (BOTDA) sensor deploying a novel polarization diversity technique based on the use of two orthogonal pump pulses which simultaneously interact with a phase modulated ... -
Random DFB fiber laser for remote (200 km) sensor monitoring using hybrid WDM/TDM
In this paper, a random distributed feedback fiber laser is proposed as a multiplexing scheme for ultralong range measurements (up to 200 km). Optical fiber sensors are time and wavelength multiplexed overcoming one of the ... -
Random fiber lasers: application to fiber optic sensors networks
Recently, random mirrors have been proposed as a method to create fiber laser cavities. This kind of cavity is based on cooperative Rayleigh scattering, which is generated along a fiber due to the material inhomogeneities ... -
Real-time FFT analysis for interferometric sensors multiplexing
In this paper, a theoretical and experimental study of two interferometric sensor multiplexing schemes has been carried out by means of the fast Fourier transform (FFT) analysis. This work addresses one of the main drawbacks ... -
Sensitivity enhancement experimental demonstration using a low cutoff wavelength SMS modified structure coated with a pH sensitive film
The multimode interference (MMI) effect in a single mode-multimode-single mode (SMS) can be used fordevelopment of wavelength shift detection based sensors. In this work, the focus is centered on obtainingwavelength shifts ... -
Sensors based on thin-film coated cladding removed multimode optical fiber and single-mode multimode single-mode fiber: a comparative study
Two simple optical fibre structures that do not require the inscription of a grating, a cladding removed multimode optical fibre (CRMOF) and a single-mode multimode single-mode structure (SMS), are compared in terms of ... -
Simultaneous measurement of humidity and temperature based on a partially coated optical fiber long period grating
A humidity and temperature optical fiber sensor based on a long-period grating (LPG), which can provide simultaneous response to both magnitudes, is proposed and demonstrated via experiments. Previously, the LPG was fully ... -
Spatial-frequency multiplexing of high-sensitivity liquid level sensors based on multimode interference micro-fibers
This paper shows a new fiber optic sensor multiplexed system for liquid level sensing. Biconical fibertapers converging at a 40 mm-long micro-fiber are used as transducers. The tapers are designed to providethe propagation ... -
Tapered single-mode optical fiber pH sensor based on lossy mode resonances generated by a polymeric thin-film
Lossy mode resonances can be generated with certain polymeric nanostructures, such as those obtained with a multilayered assembly of poly(allylamine hydrochloride) and poly (acrylic acid). This coating is adsorbed by the ...