Fiber-optic Setup Research Articles

UltraHigh Bit-Rate Hybrid DWDM Optical System Design Using DP-QPSK Modulation

Abstract In this work, an optical hybrid communication system is proposed. It is a combination of diffused link (DL) configuration of free space optics (FSO) setup and fiber optic setup. It is a 16-channel dense wavelength division multiplexing (DWDM) system, with 400 Gbps/channel data rate. It uses dual polarization-quadrature phase shift keying (DP-QPSK) modulation technique for all the setups. Bit error rate (BER), eye diagram, quality actor (Q-factor), optical time domain reflectometer (OTDR), optical spectrum analyzer (OSA) signals are considered as performance parameters of the proposed system. It is found that the link distance is 340 m for DL setup and 1,000 km for fiber setup. The system will be very much useful for solving first mile, last mile problem with long distance optical communication applications in 5 G era.

Two-photon optical imaging, spectral and fluorescence lifetime analysis to discriminate urothelial carcinoma grades.

In the framework of urologic oncology, mini-invasive procedures have increased in the last few decades particularly for urothelial carcinoma. One of the essential elements in the management of this disease is still the diagnosis, which strongly influences the choice of treatment. The histopathologic evaluation of the tumor grade is a keystone of diagnosis, and tumor characterization is not possible with just a macroscopic evaluation. Even today intraoperative evaluation remains difficult despite the emergence of new technologies which use exogenous fluorophore. This study assessed an optical multimodal technique based on endogenous fluorescence, combining qualitative and quantitative analysis, for the diagnostic of urothelial carcinoma. It was found that the combination of two-photon fluorescence, second harmonic generation microscopy, spectral analysis and fluorescence lifetime imaging were all able to discriminate tumor from healthy tissue, and to determine the grade of tumors. Spectral analysis of fluorescence intensity and the redox ratio used as quantitative evaluations showed statistical differences between low-grade and high-grade tumors. These results showed that multimodal optical analysis is a promising technology for the development of an optical fiber setup designed for an intraoperative diagnosis of urothelial carcinoma in the area of endo-urology.

Facile Fabrication of Novel Sensing System for Size Detection of Nanoparticles

We report a novel platform for sensing different sizes of noble metal nanoparticles. Exploiting evanescent field-based excitation of localized surface plasmon resonance (LSPR), gold, and silver nanoparticles are immobilized on to surface of a U-shaped silica optical fiber with a bending diameter of 0.5 cm. We contemplate variation in LSPR responses with respect to diverse sizes ranging from ∼5 to 60 nm of nanoparticles in this all fiber optic setup. Further, examining coefficient of excitation of different sized nanoparticles yielded by simulation shows good matching with experimental results. While gold nanoparticle immobilized LSPR response provides better sensitivity, the response achieved from silver nanoparticle are much more stabilized. The successful proof-of-concept fabrication of LSPR-enhanced silica fiber is the first step of its kind in generating facile size measurement.

MP54-18 QUANTITATIVE AND QUALITATIVE MULTIMODAL OPTICAL ANALYSIS TO DISCRIMINATE UROTHELIAL CARCINOMA GRADES

You have accessJournal of UrologyBladder Cancer: Basic Research & Pathophysiology I1 Apr 2018MP54-18 QUANTITATIVE AND QUALITATIVE MULTIMODAL OPTICAL ANALYSIS TO DISCRIMINATE UROTHELIAL CARCINOMA GRADES Benjamin PRADERE, Fanny Poulon, Steeve Doizi, Olivier Cussenot, Eva Compérat, Darine Abi Haidar, and Olivier Traxer Benjamin PRADEREBenjamin PRADERE More articles by this author , Fanny PoulonFanny Poulon More articles by this author , Steeve DoiziSteeve Doizi More articles by this author , Olivier CussenotOlivier Cussenot More articles by this author , Eva CompératEva Compérat More articles by this author , Darine Abi HaidarDarine Abi Haidar More articles by this author , and Olivier TraxerOlivier Traxer More articles by this author View All Author Informationhttps://doi.org/10.1016/j.juro.2018.02.1709AboutPDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareFacebookTwitterLinked InEmail INTRODUCTION AND OBJECTIVES In the framework of urologic oncology, mini-invasive procedures have increased the last decades particularly for urothelial carcinoma. One of the essential step in the management of this disease stay the diagnostic, which strongly impacts the treatment choice. The histopathologic evaluation of the grade of the tumor is a keystone of the diagnosis, and its recognition is not possible with a macroscopic evaluation. Nowadays, this specific intraoperative characteristic evaluation remains difficult despite the emergence of new technologies which use exogenous fluorophore. In our study, we assessed the use of an optical multimodal technique based on endogenous fluorescence combining qualitative and quantitative analysis for the diagnostic of urothelial carcinoma grades. METHODS Urothelial samples from bladder and upper urinary tract were prospectively included (IRB-00003835) and analyzed on a specific optical multimodal setup based on endogenous fluorescence.The analysis included qualitative analyses with two-photons fluorescence imaging (TPF) and quantitative analyses with spectral analyses and fluorescence lifetime imaging (FLIM). Qualitative analyses were compared with pathological examination. Quantitative analyses was performed with a 870nm excitation wavelength, in the spectral analysis we evaluated the spectra, the redox ratio (NADH and FAD) and the fluorescence lifetime for each sample. RESULTS We identified 3 major urothelial aspects by TPF. All this samples were correlated with pathological examinations, and permitted to differentiate healthy tissue from low and high grade urothelial carcinoma. In the quantitative analysis, the spectral results shown that the intensity level of the emitted spectra was correlated with the histopathological characteristics: the higher the grade was, the lower was the fluorescence signal. The redox ratio analysis was significantly higher in the healthy urothelium compared with tumors samples (p<0.001). Moreover, we were able to discriminate low grade from high grade tumors, the low grade had a significantly higher redox ratio (p=0.002). We were able to identify the cells structure in the FLIM images and to compare the different grade. This analysis also permitted to discriminate the different origins. The average lifetime in low grade tumor appeared shorter on our images and in the histogram shown significant differences between healthy, low grade and high grade urothelial carcinoma: healthy vs. low grade (p = 0.002), healthy vs. high grade (p < 0.001) and high grade vs. low grade (p < 0.001). CONCLUSIONS Those results show that multimodal optical analysis was able to discriminate low grade from high grade urothelial carcinoma without using exogenous fluorophore. This is a promising technology for the development of an optical fiber setup designed for an intraoperative diagnosis of urothelial carcinoma in the area of endourology. © 2018FiguresReferencesRelatedDetails Volume 199Issue 4SApril 2018Page: e719 Advertisement Copyright & Permissions© 2018MetricsAuthor Information Benjamin PRADERE More articles by this author Fanny Poulon More articles by this author Steeve Doizi More articles by this author Olivier Cussenot More articles by this author Eva Compérat More articles by this author Darine Abi Haidar More articles by this author Olivier Traxer More articles by this author Expand All Advertisement Advertisement PDF downloadLoading ...

Design, fabrication and optical characterizations of large-area lithography-free ultrathin multilayer selective solar coatings with excellent thermal stability in air

A sub-micron-thick selective multilayer solar thermal absorber made of tungsten, SiO2 and Si3N4 multilayer thin films was theoretically designed and experimentally demonstrated in this work. The optical performance was optimized by the particle swarm optimization algorithm for this multilayer absorber, whose spectral selectivity is associated with the Fabry-Perot resonance and anti-reflection effects. The designed multilayer absorber was deposited by sputtering and chemical vapor deposition techniques on the wafer scale. Its spectral absorptance characterized by a Fourier Transform Infrared spectrometer (FTIR) was demonstrated to be greater than 0.95 in the solar spectrum and less than 0.1 emittance in the mid-infrared with angular insensitivity. Temperature dependent FTIR measurements with an optical fiber setup revealed stable optical performance up to 600°C in ambient, while thermal cycle testing showed its long-term thermal stability at 400°C. Theoretical analysis of solar to power efficiency for a Carnot heat engine driven by the Solar heat was performed, which clearly shows that the proposed ultrathin selective multilayer absorber with spectral selectivity, angular insensitivity as well as high temperature stability could significantly boost the conversion efficiency of solar thermal systems at mid to high temperatures.

Dispersive Dam-Break Flow of a Photon Fluid.

We investigate the temporal photonic analogue of the dam-break phenomenon for shallow water by exploiting a fiber optics setup. We clearly observe the decay of the steplike input (photonic dam) into a pair of oppositely propagating rarefaction wave and dispersive shock wave. Our results show evidence for a critical transition of the dispersive shock into a self-cavitating state. The detailed observation of the cavitating state dynamics allows for a fully quantitative test of the Whitham modulation theory applied to the universal defocusing nonlinear Schrödinger equation.

Local Sampling of the Wigner Function at Telecom Wavelength with Loss-Tolerant Detection of Photon Statistics.

We report the experimental point-by-point sampling of the Wigner function for nonclassical states created in an ultrafast pulsed type-II parametric down-conversion source. We use a loss-tolerant time-multiplexed detector based on a fiber-optical setup and a pair of photon-number-resolving avalanche photodiodes. By capitalizing on an expedient data-pattern tomography, we assess the properties of the light states with outstanding accuracy. The method allows us to reliably infer the squeezing of genuine two-mode states without any phase reference.

Rapid remote detection of Escherichia coli via a reporter-hydrogel coated glass fiber tip

In this work the development of a responsive hydrogel coating for the remote sensing of bacterial enzymes is reported for the selective, sensitive and rapid in situ detection of (pathogenic) bacteria. The approach is based on the combination of a portable optical fiber setup with a self-reporting hydrogel applied as a coating on the glass fiber tip. To implement the enzyme sensing function, chitosan was functionalized with the chromogenic substrate 5-bromo-4-chloro-3-indolyl-β-d-glucuronide (XGlcA), which releases a non-leaching dimerized indigo dye into the hydrogel upon reaction with the enzyme β-glucuronidase (β-GUS), which is secreted by >98% of all known Escherichia coli strains. The intense blue color of the dimerized indole can be detected by bare eye in hydrogel films and, as shown here for the first time, at the tip of a glass fiber sensor. Detailed investigations of the enzymatic reaction in neat enzyme solution as well as in bacterial supernatant revealed the apparent reaction kinetics and allowed us to determine the concentration of β-GUS in the supernatant. Under optimized conditions the portable optical fiber can sense within 5min the presence of β-GUS with a limit of detection of <40nM.

Time-multiplexed measurements of nonclassical light at telecom wavelengths

We report the experimental reconstruction of the statistical properties of an ultrafast pulsed type-II parametric down conversion source in a periodically poled KTP waveguide at telecom wavelengths, with almost perfect photon-number correlations. We used a photon-number-resolving time-multiplexed detector based on a fiber-optical setup and a pair of avalanche photodiodes. By resorting to a germane data-pattern tomography, we assess the properties of the nonclassical light states states with unprecedented precision.

Quantification of doxorubicin in biofluids using white light excitation fluorescence

A fiber optic spectrometer setup was designed for white light excitation fluorescence 'WLEF' based measurements. Using this setup, two different analytical methods, a self referencing ratio-metric and a difference WLEF methods, were developed for the quantification of doxorubicin (DXR) in biofluids. It was seen that Acetonitrile (ACN) acts as an efficient and transparent extracting medium for DXR. The figures of merit and the percent recoveries of DXR in blood serum, even in presence of external fluorophores and in urine samples are comparable with existing analytical methods. The compact spectrometer is expected to be useful for easy quantification of fluorescent pharmaceuticals in biofluids.

Measuring heat balance residual at lake surface using Distributed Temperature Sensing

This research presents a new method to verify the measurements of surface fluxes and the heat balance at a lake surface, by means of Distributed Temperature Sensing (DTS) measurements from 0.5 m above to 1.5 m below the surface. Using a polyvinyl chloride hyperboloid construction, a floating standalone measuring device was developed. Being an open construction, it is almost insensitive to direct radiation. With this construction, a spiral‐shaped fiberoptic cable setup was created that obtained temperature measurements with a vertical spatial resolution of 0.0002 m and a temporal resolution of 1 min. DTS measured the detailed variations in air and surface water temperature. The new method was tested in the deep Lake Kinneret (Israel) from 6 to 9 Oct 2011 and in the shallow Lake Binaba (Ghana) from 24 to 28 Oct 2011. With the developed method, it is possible to capture the heat storage change in the top water layer, and therefore verify the water surface heat balance on a time scale of several minutes. Furthermore, a comparison was made between the measured temperature profiles of the airwater interface in Lake Kinneret and Lake Binaba. It was shown that the usage of DTS measurements for the verification of surface energy balance was applicable for Lake Kinneret, but probably not suitable for the conditions in the shallow Lake Binaba. In the latter, heat storage changes near the lake surface were not only caused by surface energy fluxes, but by internal heat waves and currents that bring cooler water to the upper layer.

Label-free optical detection of cells grown in 3D silicon microstructures

We demonstrate high aspect-ratio photonic crystals that could serve as three-dimensional (3D) microincubators for cell culture and also provide label-free optical detection of the cells. The investigated microstructures, fabricated by electrochemical micromachining of standard silicon wafers, consist of periodic arrays of silicon walls separated by narrow deeply etched air-gaps (50 μm high and 5 μm wide) and feature the typical spectral properties of photonic crystals in the wavelength range 1.0-1.7 μm: their spectral reflectivity is characterized by wavelength regions where reflectivity is high (photonic bandgaps), separated by narrow wavelength regions where reflectivity is very low. In this work, we show that the presence of cells, grown inside the gaps, strongly affects light propagation across the photonic crystal and, therefore, its spectral reflectivity. Exploiting a label-free optical detection method, based on a fiberoptic setup, we are able to probe the extension of cells adherent to the vertical silicon walls with a non-invasive direct testing. In particular, the intensity ratio at two wavelengths is the experimental parameter that can be well correlated to the cell spreading on the silicon wall inside the gaps.

Measurement of Photon Statistics with Live Photoreceptor Cells

We analyzed the electrophysiological response of an isolated rod photoreceptor of Xenopus laevis under stimulation by coherent and pseudothermal light sources. Using the suction-electrode technique for single cell recordings and a fiber optics setup for light delivery allowed measurements of the major statistical characteristics of the rod response. The results indicate differences in average responses of rod cells to coherent and pseudothermal light of the same intensity and also differences in signal-to-noise ratios and second-order intensity correlation functions. These findings should be relevant for interdisciplinary studies seeking applications of quantum optics in biology.

A compact multi-channel fluorescence sensor with ambient light suppression

A multi-channel fluorescence sensor has been developed for process monitoring and fluorescence diagnostics. It comprises a fiber-optic set-up with an immersion probe and an intensity-modulated high power ultraviolet light-emitting diode as a light source for fluorescence excitation. By applying an electronic lock-in procedure, fluorescence signals are selectively detectable at ambient light levels of 1000 000 times higher intensity. The sensor was designed to be compact, low cost and easily adaptable to a wide field of application. The set-up was used to simultaneously monitor three important metabolic fluorophores: NAD(P)H, flavins and porphyrins during the cultivation of a baker's yeast. Moreover, the accumulation and degradation kinetics of protoporphyrin IX induced by 5-aminolevulinic acid on the skin could be recorded by the sensor. The detection limit for protoporphyrin IX was determined to be 4 × 10−11 mol L−1. The linear signal amplification of the sensor and time courses of fluorescence signals monitored during yeast fermentations were validated using a commercial CCD spectrometer. The robust and flexible set-up of the fiber-optic measurement system promises easy implementation of this non-invasive analytical tool to fluorescence monitoring and diagnostics in R&D and production.

Spectral and Optimized Marks for Qualitative Material Discrimination

A method for automatic qualitative classification of liquid samples based on their absorption spectrum in the ultraviolet, visible and near-infrared regions is presented. A fiber-optic setup has been employed for material characterization. A simple technique based on image matching is proposed to perform spectra comparison. This alternative implementation of conventional spectrum matching methodologies can be easily translated to hardware platforms thus improving the time response of the classification system. The proposed method does not make any assumption on the probability density function of the data and it is also capable of automatic outlier removal. “Spectral marks” based on the polar representation of the absorption spectra and their “optimized marks” improved by means of Principal Component Analysis have been implemented. Preliminary discrimination results have been obtained on the classification of different oil samples from seeds and olives.

On-line carbon balance of yeast fermentations using miniaturized optical sensors

Monitoring of microbiological processes using optical sensors and spectrometers has gained in importance over the past few years due to its advantage in enabling non-invasive on-line analysis. Near-infrared (NIR) and mid-infrared (MIR) spectrometer set-ups in combination with multivariate calibrations have already been successfully employed for the simultaneous determination of different metabolites in microbiological processes. Photometric sensors, in addition to their low price compared to spectrometer set-ups, have the advantage of being compact and are easy to calibrate and operate. In this work, the detection of ethanol and CO(2) in the exhaust gas during aerobic yeast fermentation was performed by two photometric gas analyzers, and dry yeast biomass was monitored using a fiber optic backscatter set-up. The optical sensors could be easily fitted to the bioreactor and exhibited high robustness during measuring. The ethanol content of the fermentation broth was monitored on-line by measuring the ethanol concentration in the fermentation exhaust and applying a conversion factor. The vapor/liquid equilibrium and the associated conversion factor strongly depend on the process parameter temperature but not on aeration and stirring rate. Dry yeast biomass was determined in-line by a backscattering signal applying a linear calibration. An on-line balance with a recovery rate of 95-97% for carbon was achieved with the use of three optical sensors (two infrared gas analyzers and one fiber optic backscatter set-up).

Novel Dynamic Rotor and Blade Deformation and Vibration Monitoring Technique

Monitoring rotor deformations and vibrations dynamically is an important task for improving both the safety and the lifetime as well as the energy efficiency of motors and turbo machines. However, due to the high rotor speed encountered in particular at turbo machines, this requires concurrently high measurement rate and high accuracy, which is hardly possible to achieve with currently available measurement techniques. To solve this problem, in this paper, we present a novel nonincremental interferometric optical sensor that measures simultaneously the in-plane velocity and the out-of-plane position of laterally moving objects with micrometer precision and concurrently with microsecond temporal resolution. It will be shown that this sensor exhibits the outstanding feature that its measurement uncertainty is generally independent of the object velocity, which enables precise deformation and vibration measurements also at high rotor speed. Moreover, this sensor does not require an in situ calibration and it allows a direct measurement of blade velocity variations in contrast to blade tip timing systems. For application under harsh environmental conditions such as high temperatures, a robust and miniaturized fiber-optic sensor setup was developed. To demonstrate the capability of this sensor, measurements of tip clearance changes and rotor blade vibrations at varying operating conditions of a transonic centrifugal compressor test rig at blade tip velocities up to 600 m/s are presented among others.

A Planar Resonant Structure Sensitive to Out-of-plane Forces

We present a novel force sensor designed to facilitate force measurement deployment in various applications such as load cells or force sensitive surfaces. This force sensor can indeed inherently sense out-of-plane forces. It is a monolithic structure that integrates two resonators and provides a steady area. If a perpendicular force is applied on this steady area, a frequency shift of the two resonators occurs. The amount of force applied can thus be estimated by monitoring the frequency of the resonators. As a proof of concept, we report the fabrication and experimental characterization of a first prototype. Under atmospheric pressures, our prototype currently offers a quality factor of ∼700, and a linear displacement sensitivity of ∼5.75Hz/μm. In addition, we report the implementation of a compact and low-cost optical fiber setup to monitor the resonators’ frequency.

Using single-photon detectors for quantum key distribution in an experimental fiber-optic communication system

This paper gives experimental results of quantum key distribution on a fiber-optic setup at a telecom wavelength of 1555 nm. A self-compensated two-channel optical circuit is used. Quantum key distribution was performed by coding the phase states of single photons radiated by a pulsed semiconductor laser in two alternative nonorthogonal bases. Specially developed single photon counters based on InGaAs: InP avalanche photodiodes were employed as high-sensitivity photodetectors. The results of investigation of the quantum efficiency, probability of afterpulses, and noise level for various operating modes of the detectors at temperatures from −40 to −60°C are given. A key distribution rate of 450 bit/s was obtained for a single-mode fiber-optic quantum communication channel between the receiver and sender 25 km long at a laser pulse clock frequency of 5 MHz and an average number of photons per pulse of about 0.2. For the achieved photodetector characteristics, the average number of errors in the quantum key did not exceed 3.7%.

Coherent detection of nonlinear nanomechanical motion using a stroboscopic downconversion technique

A method is presented that overcomes bandwidth limitations arising in a fiber-optic setup transducing mechanical motion. The reflected light from a sample incorporating a nanomechanical resonator is analyzed. Modulating the incoming laser intensity at a suitably chosen frequency, the mechanically induced oscillation of the reflected light is coherently downconverted to a frequency within the detection bandwidth. Additionally, based on the mechanical nonlinear response, the optical signal can be quantitatively converted into displacement, yielding a sensitivity of 7 pm/Hz at optical power levels of 20 μW. We detect and image mechanical modes up to the seventh harmonic of the fundamental mode at 7.7 MHz.