3737results about "Material capacitance" patented technology

A glucose sensor in the form of a skin patch 2 has a microneedle 4 which painlessly penetrates the skin to draw out interstitial fluid. The interstitial fluid passes to a common entrance port 7. A series of microchannels 8 is provided on the skin patch. The fluid drawn onto the patch is selectively switched between a number of microchannels 8 by means of electro-osmotic pumps 10 and hydrophobic gates 12. Each microchannel 8 has an electrochemical detector 11 for sensing gluocse concentration. Also disclosed is a monlithic device with an integrated lance 83.

A device and method for measuring clotting times in a fluid, typically blood, within a microchannel, with the onset of clotting being determined by measurement of the rate of change, or the value, of capacitance or impedance between two electrodes situated on either side of the microchannel. The device includes an upper support member and a lower support member with a microchannel formed therein. The device also includes electrodes situated along the length of the microchannel.

A seat for a passenger vehicle is provided that comprises a first sensor for detecting the presence or absence of an occupant in the seat and a second sensor for validating the seat occupancy. The seat further comprises a transmitter for transmitting a signal indicative of valid occupancy of the seat. The first sensor may be a non-contact, capacitive sensor and the second sensor may comprise a near-field communication device for receiving a seat validation code. A seat validation system may be established on a passenger vehicle such as a train, wherein a central controller may report on seat occupancy status for the vehicle.

A method and apparatus that use complex impedance measurements of tissue in human or animal bodies for the detection and characterization of medical pathologies is disclosed. An analysis of the complex impedance measurements is performed by a trained evaluation system that uses a nonlinear continuum model to analyze the resistive, capacitive, and inductive measurements collected from a plurality of sensing electrodes. The analysis of the impedance measurements results in the construction of a multidimensional space that defines the tissue characteristics, which the trained evaluation system uses to detect and characterize pathologies. The method and apparatus are sufficiently general to be applied to various types of human and animal tissues for the analysis of various types of medical pathologies.

A biosensor apparatus and method with sample type and cell volume detection. The apparatus includes a sine wave generator to apply an AC signal to a biosensor cell containing a sample, a current-to-voltage converter, a phase shifter, a square wave generator, a synchronous demodulator, and a low pass filter which yields a signal proportional to the effective capacitance across the biosensor cell, which is proportional to the volume of the sample. In addition, the current-to-voltage converter yields a signal indicative of the type of sample contained within the biosensor cell. The method includes applying a sine wave to the biosensor cell, shifting the phase of the resultant signal, generating a square wave synchronous with the sine wave, demodulating the resultant signal with the square wave, and filtering the demodulated signal to produce a signal proportional to the effective capacitance across the biosensor cell. The biosensor apparatus and method are capable of determining sample type and measuring glucose levels over a wide range of sample volumes.

Methods and systems are provided for determining whether a volume of biological sample is adequate to produce an accurate electrochemical analyte concentration measurement. Certain such methods and systems provide the additional function of compensating for a sample volume determined to be less than adequate in order to proceed with an accurate analyte concentration measurement. The present invention is employed with a biosensor, such as an electrochemical test strip to which the sample volume of biological solution is deposited, and a meter configured to receive such test strip and to measure the concentration of selected analytes within the biological sample.

A method and apparatus for performing a first measurement on a biological fluid or control, which first measurement varies with both the concentration of a first component and at least one of the presence and concentration of a second component. The method and apparatus perform a second measurement on the biological fluid or control, which second measurement varies primarily only with the at least one of the presence and concentration of the second component to develop an indication of the at least one of the presence and concentration of the second component. The first and second measurements may be made sequentially or simultaneously. The method and apparatus then remove an amount representative of the indicated presence or concentration of the second component from the concentration of the first component indicated by the first measurement.

Sensor platforms and methods of making them are described. A platform having a non-horizontally oriented sensor element comprising one or more nanostructures such as nanotubes is described. Under certain embodiments, a sensor element has or is made to have an affinity for an analyte. Under certain embodiments, such a sensor element comprises one or more pristine nanotubes. Under certain embodiments, the sensor element comprises derivatized or functionalized nanotubes. Under certain embodiments, a sensor is made by providing a support structure; providing one or more nanotubes on the structure to provide material for a sensor element; and providing circuitry to electrically sense the sensor element's electrical characterization. Under certain embodiments, the sensor element comprises pre-derivatized or pre-functionalized nanotubes. Under other embodiments, sensor material is derivatized or functionalized after provision on the structure or after patterning. Under certain embodiments, a large-scale array of sensor platforms includes a plurality of sensor elements.

Multi functional sensors are described. A silicon based sensor utilizes metal layers arranged as resistors around a central pair if resistors separated by a humidity sensitive polymer with one of the central resistors being a heater. This enables temperature humidity wind speed and direction to be measured. In another embodiment an array of resistors is printed onto a flexible substrate to form the basis of an array of sensors. A soil moisture sensor, which is also useful as a leaf wetness sensor, incorporates a novel self calibrating capacitive sensor structure. The flexible substrate is rolled into a stake that can be inserted in the soil so that below ground sensors measure soil moisture and above ground sensors measure temperature, light, humidity, wind speed and direction.

In-line thickness measurement of a dielectric film layer on a surface of a workpiece subsequent to a polishing on a chemical-mechanical polishing machine in a polishing slurry is disclosed. The workpiece includes a given level of back-end-of-line (BEOL) structure including junctions. The measurement apparatus includes a platen and an electrode embedded within the platen. A positioning mechanism positions the workpiece above the electrode with the dielectric layer facing in a direction of the electrode. A slurry dam is used for maintaining a prescribed level of a conductive polishing slurry above the electrode, the prescribed level to ensure a desired slurry coverage of the workpiece. A capacitance sensor senses a system capacitance C in accordance with an RC equivalent circuit model, wherein the RC equivalent circuit includes a resistance R representative of the slurry and workpiece resistances and the system capacitance C representative of the dielectric material and junction capacitances. Lastly, a capacitance-to-thickness converter converts the sensed capacitance to a dielectric thickness in accordance with a prescribed system capacitance / optical thickness calibration, wherein the prescribed calibration corresponds to the given level of BEOL structure of the workpiece.

The present invention (also identified as “Capacitance cytometry”) relates to microfluidic and nanofluidic devices for detecting or measuring an electrical property of a fluid (liquid or aerosol), a single molecule, particle, or cell in fluid. In a particular embodiment, the devices detect or measure changes in capacitance of a fluid, molecule, particle or cell as it passes through the device. The invention relates to detection and measurement of single molecules, particularly biological molecules, and to methods of sequencing polynucleotide molecules (RNA or DNA) by detecting differentially labeled single nucleotides. Single molecule detection applications include DNA or RNA sequencing, detection of SNPs, protoemics, and particle sizing. The device can be used to determine cell DNA content, to analyze cell-cycle kinetics of cell populations, and to assay for abnormal changes in cell DNA content. Nano-microfluidic devices of this invention also have utility as detectors in molecular sorting systems and for detecting pathogens.

A method for monitoring a select analyte in a sample in an electrochemical system. The method includes applying to the electrochemical system a time-varying potential superimposed on a DC potential to generate a signal; and discerning from the signal a contribution from the select analyte by resolving an estimation equation based on a Faradaic signal component and a nonfaradaic signal component.

A system and method for predicting structural failure of a wall of a fluid containment vessel, such as a hydraulic hose or other type of pressurized conduit of types used in mobile machinery, automotive, aerospace, manufacturing, and process equipment. The wall of the vessel has an innermost layer for contact with the fluid contained by the vessel, and an outermost layer parallel with the innermost layer. The system includes strain-sensing means between the innermost and outermost layers and comprising at least one conductor parallel to the innermost layer of the wall. The system and method entail sensing changes in an electrical property associated with the at least one conductor resulting from distortion of the wall of the vessel causing distortion of the at least one conductor.

A method and apparatus are described for sensing the absolute humidity of gases where the relative humidity of gases are measured, the humidity transducer is heated, the resulting temperature measured and the absolute humidity calculated (based on the power to heat said transducer, the temperature of said transducer and the relative humidity).In further embodiments the humidity transducer may be heated to a pasteurisation temperature, to substantially kill any common pathogens present on the humidity transducer. The flow rate may be determined to estimate a more instantaneous valve of humidity. The operation of the sensor may be continually monitored for correct operation and various constructions disclosed for improving the efficiency of operation.

Methods and apparatus are provided for obtaining a representation of the distribution of electrical impedance within a multiphase flow with an electrically continuous or discontinuous principle flow contained within an electrically conductive solid ring electrode, including providing a plurality of mutually spaced electrical contacts mounted at the outside wall of the ring and electrically contacting with the ring, applying currents or voltages to the ring from the electrical contacts, generating a more homogeneous electric field distribution within the material, measuring voltage or current distribution alone the ring from other electrical contacts, relatively intensifying the imaging sensitivity at the central area of the sensing domain using a π / 2 angle sensing strategy and reconstructing the representation of the impedance distribution using CG method with an error processing strategy.

A biosensor apparatus and method with sample type and cell volume detection. The apparatus includes a sine wave generator to apply an AC signal to a biosensor cell containing a sample, a current-to-voltage converter, a phase shifter, a square wave generator, a synchronous demodulator, and a low pass filter which yields a signal proportional to the effective capacitance across the biosensor cell, which is proportional to the volume of the sample. In addition, the current-to-voltage converter yields a signal indicative of the type of sample contained within the biosensor cell. The method includes applying a sine wave to the biosensor cell, shifting the phase of the resultant signal, generating a square wave synchronous with the sine wave, demodulating the resultant signal with the square wave, and filtering the demodulated signal to produce a signal proportional to the effective capacitance across the biosensor cell. The biosensor apparatus and method are capable of determining sample type and measuring glucose levels over a wide range of sample volumes.

A washer assembly is for use with a fastener. The washer assembly includes a first conductive portion, a second conductive portion, and an insulating portion disposed between the first conductive portion and the second conductive portion. The first conductive portion, the second conductive portion, and the insulating portion form a variable capacitor having a capacitance based on an amount of force applied thereto by the fastener. A wireless transponder unit includes a control unit electrically connected to the variable capacitor and an antenna electrically connected to the control unit. The control unit is configured to sense the capacitance of the variable capacitor, to generate information representing the capacitance, and to output the information to a wireless reader unit via the antenna.

The invention discloses a passive wireless temperature and humidity integrated sensor. A cantilever beam capacitive temperature sensor and an interdigital capacitive humidity sensor are adopted, and the passive wireless temperature and humidity integrated sensor comprises a semiconductor substrate, a lower dielectric layer, a lower metal layer, an intermediate dielectric layer, an intermediate metal layer, an upper dielectric layer, and an upper metal interconnecting line and humidity-sensitive material positioned on the upper surface of the upper dielectric layer. The cantilever beam capacitive temperature sensor, an inductance loop and interdigital capacitive humidity sensor and an inductance loop work in a frequency division mode, the temperature and humidity are wirelessly measured, and the passive wireless temperature and humidity integrated sensor can be applied to measuring and acquiring two parameters, namely the temperature and humidity, in a closed environment or severe conditions. The sensor is manufactured by a complementary metal oxide semiconductor (CMOS) micro-electromechanical system (MEMS) process, and has high performance and low cost.

A moisture detection sensor includes a resonant circuit composed of an antenna coil 53 and a capacitor C. A noncontact tag composed of covering materials 51 and 57 covers the resonant circuit. The capacitor C has a pair of electrodes 52 and 56 and a dielectric 55 interposed between the electrodes 52 and 56, and the covering material 57 contains a through-hole 57a that allows the liquid to infiltrate into the dielectric 55 from outside.