By Topic

Sensors Journal, IEEE

Issue 6 • Date Dec. 2005

Filter Results

Displaying Results 1 - 25 of 47
  • [Front cover]

    Publication Year: 2005 , Page(s): c1
    Save to Project icon | Request Permissions | PDF file iconPDF (41 KB)  
    Freely Available from IEEE
  • IEEE Sensors Journal publication information

    Publication Year: 2005 , Page(s): c2
    Save to Project icon | Request Permissions | PDF file iconPDF (36 KB)  
    Freely Available from IEEE
  • Table of contents

    Publication Year: 2005 , Page(s): 1141 - 1143
    Save to Project icon | Request Permissions | PDF file iconPDF (46 KB)  
    Freely Available from IEEE
  • 2005 Reviewers List

    Publication Year: 2005 , Page(s): 1144 - 1146
    Save to Project icon | Request Permissions | PDF file iconPDF (32 KB)  
    Freely Available from IEEE
  • Electrochemical characterization and in vivo biocompatibility of a thick-film printed sensor for continuous in vivo monitoring

    Publication Year: 2005 , Page(s): 1147 - 1158
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1880 KB) |  | HTML iconHTML  

    This paper assessed the material biocompatibility and investigated the temporal modulation in electrochemical performance of printed thick-film electrochemical sensing devices (ESDs) that can serve as the basis of various enzymatic sensor in detecting an electrochemically potent species. The sensors were placed in phosphate buffered saline (PBS), human serum, or implanted subcutaneously in rats, free or in stainless steel cages. The exudate collection allowed the evaluation of inflammatory cell populations, up to 21 days. The ferrous/ferric redox electrode reactions were used to assess the electrode elements performance for up to 49 days. Following testing, scanning electron microscopy (SEM) evaluated cell surface adhesion, while fibrous capsules were examined by histology. It was determined that the exudates leukocyte concentration due to the presence of sensors was comparable to the empty cage controls. For the length of the study, the sensors functionality appeared not to be influenced by the in vivo environment, when tested ex vivo, without the surrounding fibrous capsule. Surface imaging (SEM) indicated temporal focal dissolution of the Ag/AgCl electrodes with no apparent local toxicity. We concluded that the ESDs were biocompatible and their ex vivo functionality was not lost when maintained in vivo for up to 49 days. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Surface plasmon resonance detection of metal ions: layer-by-layer assembly of polyelectrolyte sensing layers on a multichannel chip

    Publication Year: 2005 , Page(s): 1159 - 1164
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1040 KB) |  | HTML iconHTML  

    A single-chip multichannel surface plasmon resonance sensor (SPR) has been used to detect metal ions in aqueous solutions. The equipment was designed around a commercial light-emitting diode and a CCD camera and incorporated no moving parts. The sensing materials were based on molecular architectures of polyelectrolyte films, deposited by the layer-by-layer self-assembly technique. Two bilayer architectures, poly(ethyleneimine) (PEI)/poly(ethylenealt-maleic acid) and PEI/poly(styrenesulfonate), were shown to produce different responses to solutions containing copper, nickel, and iron. The SPR equipment was able to measure concentrations of these metals down to levels of at least 2×10-5 M. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Array of opto-chemical sensors based on fiber-optic spectroscopy

    Publication Year: 2005 , Page(s): 1165 - 1174
    Cited by:  Papers (5)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (400 KB) |  | HTML iconHTML  

    A compact, flexible platform for reading out the variation of the optical absorption spectra in the visible range in a number of sensing materials is illustrated in this paper. This apparatus is based on an integrated spectrophotometer, an array of suitably controlled LEDs, optical fibers to carry and collect light, and a mechanical arrangement that makes possible the measurement, in sequence, of up to 15 different sensing layers. The unit was tested with a number of metalloporphyrins, known for their outstanding sensorial and optical properties. Data were analyzed using a multiway chemometrics approach. In this regard, a methodology to investigate the properties of an array of chemical sensors is introduced. This approach allowed an evaluation of the role played in the array by each sensing material in each spectral region to be performed. The analysis revealed interesting insight into the classification properties of the sensor array and the interaction mechanisms of porphyrins. The set of metalloporphyrins showed a variety of interaction mechanisms, and the relation of these mechanisms to the structure of the metalloporphyrins was evidenced by an accurate interpretation of the loadings of the multiway analysis. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • ATR-FTIR spectroscopic analysis of sorption of aqueous analytes into polymer coatings used with guided SH-SAW sensors

    Publication Year: 2005 , Page(s): 1175 - 1184
    Cited by:  Papers (10)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (792 KB) |  | HTML iconHTML  

    Attenuated total internal reflectance Fourier transform infrared (ATR-FTIR) spectroscopy was used for the investigation of sorption of aqueous solutions of analytes into polymer coatings. A series of simple model polymers, such as poly(dimethylsiloxane), poly(epichlorhydrin), and poly(isobutylene), and films and analytes, such as aqueous solutions of ethylbenzene, xylenes, toluene, and nitrobenzene, were used to evaluate the use of ATR-FTIR spectroscopy as a screening tool for sensor development. The ratios of integrated infrared absorption bands provided a simple and efficient method for predicting trends in partition coefficients. Responses of polymer-coated guided shear horizontal surface acoustic wave (SH-SAW) sensor platforms to the series of analytes, using polymer coatings with similar viscoelastic properties, were consistent with ATR-FTIR predictions. Guided SH-SAW sensor responses were linear in all cases with respect to analyte concentration in the tested range. Comparison of ATR-FTIR data with guided SH-SAW sensor data identifies cases where mass loading is not the dominant contribution to the response of the acoustic wave sensor. ATR-FTIR spectra of nitrobenzene, coupled with computational chemistry, provided additional insight into analyte/polymer interactions. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Micromachined silicon electrolytic conductivity probes with integrated temperature sensor

    Publication Year: 2005 , Page(s): 1185 - 1196
    Cited by:  Papers (8)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1544 KB) |  | HTML iconHTML  

    Electrolytic conductivity measurements of fluids currently require sample volumes greater than a milliliter. Many applications would benefit from accurate measurements of nano- to microliter sample volumes. However, polarization and nonlinear electrode impedance effects, along with stray impedance and temperature effects, strongly affect measurements of the solution conductance for microliter and smaller sample volumes. MEMS-based silicon electrolytic conductivity probes, down to 100-μm wide, with integrated temperature sensors, have been designed and fabricated to overcome these effects. Several electrode configurations were tested: plain electrode pairs, electrode pairs plated with platinum black, plain four electrode sets, and four electrode sets plated with platinum black were investigated. The same accuracy as normal scale probes has been achieved with these sensors over almost three orders of magnitude in solution concentration and electrolytic conductivity ranges. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Core-referenced ratiometric fluorescent potassium ion sensors using self-assembled ultrathin films on europium nanoparticles

    Publication Year: 2005 , Page(s): 1197 - 1205
    Cited by:  Papers (18)  |  Patents (4)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (704 KB) |  | HTML iconHTML  

    Nanoengineered fluorescent sensor coatings on colloidal carriers have been developed for use intracellularly. These nanosensors are fabricated via the electrostatic layer-by-layer self-assembly technique to form ultrathin polyelectrolyte films containing indicators on fluorescent nanoparticles. The fluorescent nanoparticle templates and the fluorescent indicator are chosen such that their optical properties are complementary, enabling the inert nanoparticle templates to serve as internal intensity references for the fluorescent probe. In this work, the potassium ion indicator, potassium-binding benzofuran isophthalate potassium-binding benzofuran isophthalate was immobilized within poly(styrene sulfonate)/poly(allylamine hydrochloride) films assembled on the surface of fluorescent europium nanoparticles. The indicator retains its sensitivity to potassium ions after immobilization within the films and exhibits sensitivity to increases in potassium concentration over a broad range. In addition, the sensors demonstrate excellent leaching stability, with less than 1% of loaded indicator leached after 14 days of wet storage. The core-referenced nanosensor scheme described here is a simple and elegant way to co-immobilize fluorescent indicator and intensity reference within a single nanoscale package, which may be deployed intracellularly; furthermore, the separation of fluorescent indicator from the cellular environment is attractive, as it may prevent complications due to use of liquid-phase fluorescent sensors intracellularly, such as cytotoxicity and probe compartmentalization. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Measurement of 5-eV atomic oxygen using carbon based films: preliminary results

    Publication Year: 2005 , Page(s): 1206 - 1213
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1520 KB) |  | HTML iconHTML  

    Carbon-based sensors have been developed to measure the atmospheric neutral atomic oxygen (AO) flux experienced by spacecraft in low Earth orbit. Thin- and thick-film carbon sensor elements were deposited onto an alumina substrate between thick-film gold tracks and silver palladium solder pads. AO flux is deduced by measuring resistance changes as the carbon film erodes and applying a simple theory. A wide range of responses were observed that are dependent on the deposition process and post deposition annealing. The deposition methods used were dc magnetron sputtering, e-beam evaporation, and screen-printing. The sensors tested compare favorably with similar silver-based sensors that have been flown previously on small satellite missions with significant mass/power constraints. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A resonant accelerometer with two-stage microleverage mechanisms fabricated by SOI-MEMS technology

    Publication Year: 2005 , Page(s): 1214 - 1223
    Cited by:  Papers (26)  |  Patents (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1072 KB) |  | HTML iconHTML  

    We present the design, fabrication, and testing of a push-pull differential resonant accelerometer with double-ended-tuning-fork (DETF) as the inertial force sensor. The accelerometer is fabricated with the silicon-on-insulator microelectromechanical systems (MEMS) technology that bridges surface micromachining and bulk micromachining by integrating the 50-μm-thick high-aspect ratio MEMS structure with the standard circuit foundry process. Two DETF resonators serve as the force sensor measuring the acceleration through a frequency shift caused by the inertial force acting as axial loading. Two-stage microleverage mechanisms with an amplification factor of 80 are designed for force amplification to increase the overall sensitivity to 160 Hz/g, which is confirmed by the experimental value of 158 Hz/g. Trans-resistance amplifiers are designed and integrated on the same chip for output signal amplification and processing. The 50-μm thickness of the high-aspect ratio MEMS structure has no effect on the amplification factor of the mechanism but contributes to a greater capacitance force; therefore, the resonator can be actuated by a much lower ac voltage comparing to the 2-μm-thick DETF resonators. The testing results agree with the designed sensitivity for static acceleration. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A novel thermal sensor concept for flow direction and flow velocity

    Publication Year: 2005 , Page(s): 1224 - 1234
    Cited by:  Papers (8)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (480 KB) |  | HTML iconHTML  

    This paper presents a unified theory for different measurement concepts of a thermal flow sensor. Based on this theory, a new flow sensor concept is derived. The concept allows measuring both direction and velocity of a fluid flow with a heater and an array of temperature sensors. This paper first analyzes the two-dimensional (2-D) forced convection problem with a laminar flow. The two operation modes of a constant heating power and of a constant heater temperature are considered in the analytical model. A novel estimation algorithm was derived for the flow direction. Different methods for velocity measurement were presented: the hot-wire method, the calorimetric method, and the novel average-temperature method. The only geometric parameter of the sensor, the dimensionless position of the sensor array, is optimized based on the analytical results. Furthermore, the paper presents the experimental results of the sensor prototype. In order to verify the analytical model, an array of temperature sensors was used for recording the 2-D temperature profile around the heater. Temperature values are transferred to a computer by a multiplexer. A program running on a personal computer extracts the actual flow velocity and flow direction from the measured temperature data. This paper discusses different evaluation algorithms, which can be used for this sensor. A simple Gaussian estimator was derived for the direction measurement. This estimator provides the same accuracy as the analytical estimator. Velocity results of both the calorimetric concept and the novel average-temperature concept are also presented. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Noise of piezoelectric accelerometer with integral FET amplifier

    Publication Year: 2005 , Page(s): 1235 - 1242
    Cited by:  Papers (11)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (424 KB) |  | HTML iconHTML  

    Since significant progress has been achieved in the development of low-noise piezoelectric (PE) accelerometers with integral FET amplifiers, detailed noise analysis of the system PE transducer-FET amplifier, and obtaining the engineering formula for its noise floor has become vital. As a result of this analysis, the formula for the noise floor of PE accelerometers in terms of acceleration spectral density is obtained at wide frequency band. Noise floor of the low-noise PE accelerometer comprising low-noise JFET charge amplifiers with some particular parameters of the PE transducer and the JFET amplifier was measured. The theoretical and experimental curves of the PE accelerometer's noise floor have a good correlation with each other at frequencies from 1 Hz to 10 kHz. The contribution of the different noise sources to the overall noise floor is shown. Those noise sources include the mechanical-thermal noise and electrical-thermal noise of the PE transducer and all main noise sources of FET amplifiers: the thermal noise voltage of the FET biasing resistor, the thermal noise of the series resistor between the PE transducer and the gate of the FET, the channel thermal noise voltage, the 1/f noise voltage, and the shot noise current in the gate circuit. At low frequencies, the f≤50 Hz noise floor is determined mainly by the FET biasing resistor's thermal noise and the PE transducer's electrical-thermal noise. At frequencies from about 50 Hz to about 1 kHz, the contribution of the PE transducer's electrical-thermal noise dominates over the amplifier's noise sources by a factor of less than 2. At frequencies above 1 kHz, noise floor is determined mainly by the JFET channel thermal noise and the PE transducer's electrical-thermal noise. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Analysis and optimization of a compliant mechanism-based digital force/weight sensor

    Publication Year: 2005 , Page(s): 1243 - 1250
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (376 KB) |  | HTML iconHTML  

    Digital force/weight sensors have some advantages over their analog counterparts. This paper describes the optimization and implementation of a novel digital force/weight sensor that uses a thickness-shear quartz crystal resonator (QCR) and a unique compliant mechanism. The compliant mechanism consists of eight flexure hinges and is used to fix the sensitive QCR and transfer the measured force. Advantages of such a sensor include inherent digital output, high resolution, high reliability, and low cost. Due to the complex structure and the multivariables of the compliant mechanism, conventional trial methods are inefficient in determining the dimensions. To solve this problem, an optimization method has been developed by employing rigid-body model, finite element method, and nonlinear programming techniques. Experimental results show that it is more efficient than trial methods in optimizing complex compliant mechanism-based sensors. This method can be used as a generic method for optimizing force sensors using compliant mechanisms, to obtain the desired specifications. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Sensitivity, noise, and resolution in QCM sensors in liquid media

    Publication Year: 2005 , Page(s): 1251 - 1257
    Cited by:  Papers (32)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (568 KB) |  | HTML iconHTML  

    The use of quartz-crystal oscillators as high-sensitivity microbalance sensors is limited by the frequency noise present in the circuit. To characterize the behavior of the sensors, it is not enough to determine their experimental sensitivity, but, rather, it is essential to study the frequency fluctuations in order to establish the sensor resolution. This is fundamental in the case of oscillators for damping media, because the level of noise rises due to the strong decline of the quality factor of the resonator. In this paper, a comparative study of noise and resolution is presented with respect to the frequency and the quality factor. The study has been made using four oscillators designed to be used in quartz-crystal microbalance sensors in damping media. The four circuits have been designed at increasing frequencies in order to improve the sensitivity or frequency change per unit of measurand. Also, the present theoretical resolution limit or best resolution achievable with a microbalance oscillator using an AT resonator is determined, since this does not depend on frequency. However, when operating in liquid, the damping of the resonator makes the resolution diminish due to a worsening of the quality factor. The relationship between the resolution limit and the frequency and characteristics of the liquid medium is determined. The resolution worsens when the density and viscosity of the liquid is increased. However, in this case, an increase in frequency implies a small increase in resolution. Therefore, we find that when working below the maximum quality factor, for similar values, the resolution can be improved by elevating the work frequency. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Anisotropic magnetoresistive model for saturated sensor elements

    Publication Year: 2005 , Page(s): 1258 - 1263
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (480 KB) |  | HTML iconHTML  

    Presented is a model that predicts the resistive behavior of an anisotropic magnetoresistive (AMR) sensor element in magnetic saturation. Both the experimental data and the model concur with a high degree of accuracy. The model builds on the work of other investigators and it is shown to track the behavior of actual magnetoresistive elements. This paper shows that, with a minor modification to previous models, the resistor should and can be divided into isotropic and magnetically affected components that can give some new insights into the AMR effect. With this model, one can extract the parameters that have magnetic effects from the ones that are independent of the magnetic effects. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Excitation and temperature stability of PCB fluxgate sensor

    Publication Year: 2005 , Page(s): 1264 - 1269
    Cited by:  Papers (7)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (688 KB) |  | HTML iconHTML  

    Printed circuit board (PCB) integrated inductors have been adapted for operation as fluxgate sensors. A ring core is made from an electrodeposited permalloy thin film and is sandwiched between the layers of the PCB. The sensor excitation winding is also integrated into the PCB design. The pick-up coil is wound around the frame of the PCB core. Different types of current excitation waveforms with tuned and nontuned pick-up coils were used. The achieved sensitivities for 60 turns of tuned/nontuned pick-up coil, a sinusoidal waveform excitation current of Irms=300 mA, and an excitation frequency of 150 kHz were 13100/1800 V/T. The achieved sensitivity for pulse excitation (Ipeak-peak=900 mA, Irms=184 mA, duty 20%) was 2100 V/T. Noise power density for pulse excitation was 1.2 nTrms/√Hz@1 Hz, noise rms value from 10 mHz to 10 Hz was 3.3 nT. A perming error of 1 μT was measured for a wide range of excitation currents. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Development and application of millimeter wave radar sensors for underground mining

    Publication Year: 2005 , Page(s): 1270 - 1280
    Cited by:  Papers (13)  |  Patents (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1696 KB) |  | HTML iconHTML  

    This paper defines the issues that are required for the development of a successful underground range measurement sensor. It considers various options, including laser and sonar implementations, before focusing on a millimeter-wave frequency modulated continuous wave radar. The implementations of radar sensors for simple ranging and three-dimensional cavity profiling are then discussed before some data obtained in underground mines is presented to verify the radar performance through thick dust and vapor. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Complex permittivity and moisture measurements of oil palm fruits using an open-ended coaxial sensor

    Publication Year: 2005 , Page(s): 1281 - 1287
    Cited by:  Papers (12)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1112 KB) |  | HTML iconHTML  

    An open-ended coaxial sensor for the determination of complex permittivity and moisture content of oil palm fruits is presented in this paper. The measurement system consisting of the sensor and a PC-controlled vector network analyzer have been tested successfully on a range of oil palm fruits of various degrees of ripeness. The initial values of the complex permittivity were estimated using the admittance model of the sensor. The amount of moisture content was found by matching the values of permittivity from the quasistatic model with the permittivity of a dielectric mixture model using the moisture content values obtained from the standard oven drying method. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Thinned fiber Bragg gratings as refractive index sensors

    Publication Year: 2005 , Page(s): 1288 - 1295
    Cited by:  Papers (23)  |  Patents (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1320 KB) |  | HTML iconHTML  

    In this work, highly sensitive refractive index measurements have been experimentally demonstrated by using thinned fiber Bragg grating (FBG) sensors. When the cladding diameter is reduced, significant changes in the effective refractive index occur due to surrounding medium refractive index modifications, leading to Bragg wavelength shifts. Uniformly thinned FBGs have been obtained by using wet chemical etching in hydrofluoric acid solutions. In order to prove sensor sensitivity, experimental tests have been carried out by using glycerine solutions with well-known refractive indices. Obtained results agree well with the numerical analysis carried out by using the three-layer fiber model. If the cladding layer is completely removed, resolutions of ≈10-5 and ≈10-4 for the outer refractive index around 1.450 and 1.333, respectively, are possible. Finally, a novel approach based on the selective etching along the grating region has been analyzed, leading to high-sensitivity refractive index sensors based on intensity measurements. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A CMOS sensor optimized for laser spot-position detection

    Publication Year: 2005 , Page(s): 1296 - 1304
    Cited by:  Papers (6)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (888 KB) |  | HTML iconHTML  

    An optical sensor architecture optimized for flying-spot, triangulation-based, three-dimensional (3-D) laser scanners will be presented. The architecture implements a spot-position detection algorithm based on a two-step procedure that allows for improved dynamic range and readout speed. The sensor, which contains two linear arrays of pixels, analog readout channels, and digital signal preprocessing circuitry, has been fabricated in 0.6-μm CMOS double-poly triple-metal technology and measures 8.17×5.67 mm2. Pixel size and shape have been selected for reducing the effect of laser speckle and for the possibility of measuring color in a multiwavelength 3-D scanner. Electrooptical test results confirm the sensor behavior as expected from simulations on a dynamic range of 80 dB and exhibits a maximum speed of 50-k voxel/s. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A monolithic optical phase-shift detector on silicon

    Publication Year: 2005 , Page(s): 1305 - 1309
    Cited by:  Papers (6)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (968 KB) |  | HTML iconHTML  

    A novel monolithically integrated device used as an optical phase-shift detector is presented. It consists of a diffraction grating etched at the surface of a p-n photodiode fabricated by a process compatible with a standard silicon CMOS technology. When two coherent light beams are collimated toward the surface of the device, the detected optical power generates a current depending on the relative phase between the two incident beams. The operating principle of this detector and the results obtained by finite-difference time-domain modeling are presented. The fabrication process of the first devices is described and the experimental validation of the concept is demonstrated. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Curved elastic beam with opposed fiber-Bragg gratings for measurement of large displacements with temperature compensation

    Publication Year: 2005 , Page(s): 1310 - 1314
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (272 KB) |  | HTML iconHTML  

    In this paper, a temperature-compensated configuration for extending the working range of fiber-Bragg grating (FBG) strain sensors has been proposed. This technique consists of the application of two FBGs to the opposite surfaces of a straight elastic beam which was bent in a horizontal direction. The difference of the two FBGs' wavelengths depends on the beam curvature, while the mean value is taken in order to compensate for the temperature effects. The sensor proposed is less fragile than the bare fiber and seems particularly suited as large displacement sensor, and for structures in which it is impossible to affix the bare fiber, such as breaks or separate elements. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • An integrated fluorescence array as a platform for lab-on-a-chip technology using multimode interference splitters

    Publication Year: 2005 , Page(s): 1315 - 1320
    Cited by:  Papers (9)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (568 KB)  

    We present the design and fabrication of 1-to-N multimode interference (MMI) splitters, suitable for use in integrated optical fluorescence array sensing, with particular applications in lab-on-a-chip (micro-TAS) technologies. Electron beam irradiation of germanium-doped flame hydrolysis deposited silica was used to define the MMI waveguide regions. The splitters were integrated with microfluidic channels to form direct-excitation fluorescence sensor chips for use at visible wavelengths. Characterization of the waveguides shows that predictable splitting ratios can be achieved. Two devices are presented: a 1×2 splitter integrated with one analytical chamber and a 1×4 array device for multipoint excitation. A photomultiplier tube was used to assess the analytical performance of the chip, in response to standard aliquots of fluorophore (31 nM to 1.25 μM). View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.

Aims & Scope

The IEEE Sensors Journal is a peer-reviewed, monthly online/print  journal devoted to sensors and sensing phenomena

Full Aims & Scope

Meet Our Editors

Editor-in-Chief
Krikor Ozanyan
University of Manchester
Manchester, M13 9PL, U.K.