Other

Airware, Inc.

Jaesent Inc.

Gaztech International Corporation

Engelhard Sensor Technologies, Inc.

Gamelot, Inc.

Gaztech Corporation

Cummins Inc.

Privasys, Inc.

Telaire Systems, Inc.

Evionics, Inc.

C. R. Bard, Inc.

Engelhard Corporation

Edwards Systems Technology, Incorporated, Inc.

Airwave Limited

Jacob Y Wong

Roy Lee Anderson

Thomas G Campbell

Frederick H Lindner

Chi Wai Tse

John M Janssen

Larry Routhenstein

Bent Formby

Charles M Peterson

William R Bryant

Douglas Henry Marman

Ronald Marshall Heck

John Joseph Steger

Joan M Ziegler

Jordan K Lampert

Mark A Peltier

Arthur Bruce Robertson

Dennis E Ebejer

Jeff H Moser

Renyan Qin

Andrian I Kouznetsov

John R McGibbon

Delano P Chong

Daniel Tschudi

William R Bryant, Jr

Rudy W Tietze

An absorption spectroscopy process uses a single radiation beam with two or more pulsed beams (including at least a signal beam and a reference beam) that are passed into a liquid sample to a variable effective depth and then reflected out of the liquid sample where it is detected and processed to obtain a value over a preselected time. As values are determined for multiple effective depths, a sampling dataset is obtained which is used to calculate a concentration level of a targeted particle in the liquid sample by use of calibration dataset obtained from use of known samples.

Reflective depth interrogation for analyte measurement in liquids

Increased precision for liquid absorption spectroscopy, especially for in vivo samples of human analytes, is obtained by varying the signal or signal and interference central wavelengths when the temperature of the sample site varies beyond a selected threshold used for determining standardized signal or signal and interference central wavelengths. The amount of variance for a central wavelength of the signal beam which includes 1,150 nm is approximately 2 nm or less.

Temperature adjusted modulation of a signal center wavelength in liquid absorption spectroscopy

A process quantifies a concentration of a targeted molecule in a liquid sample by pulsing signal and reference beams from their own sources, then spatially combining the pulsed beams into a single radiation beam which passes into the liquid sample and then detecting pulsed output beams after the single radiation beam passes out of the liquid sample. The pulsed outputs of the signal and reference beams are processed to obtain a value over a preselected period of time and, if an interference beam is used, it is processed with the reference beam to obtain a calibration curve adjustment representative of optical interference represented by at least one interfering molecule concentration which is used to calculate the concentration level of the targeted particle in the liquid sample. Two detectors, which may have an optical co-axial configuration, can be used for detection of pulsed beams.

Minimization of noise in optical data capture for liquids

The concentration of a targeted molecule (such as glucose) in a liquid medium having at least one interfering molecule coexisting with the targeted molecule is detected by use of NDIR and a sampling technique in which an imposed location of a pulse beam from a signal source, an interference source and a reference source is varied over a plurality of sites of a sampling area.

Enhanced optical data capture using NDIR for liquids

A process and sensor system useful for determining a concentration of a targeted molecule M (such as glucose) within a given time period in a liquid sampling matrix wherein the sample volume is configured so that a sampling error caused by changes of the targeted molecule passing in and out of the sample volume is approximately the same or less than a measurement error caused by an accuracy limit of electronic components and optical elements used in the sensor system.

For determining concentration of targeted molecules Min a liquid sample admixed with interfering molecules Mwhich overlap their absorption band, a special NDIR sampling and calibration technique is employed. Besides the signal source, a reference and one or more interference sources are added. The selection of the wavelength for the interference sources enables its measured transmittance value to be used for deciding the validity of the calibration curve for molecules Min the liquid sample. This value can further be used to adjust the calibration curve via a parameter linking the transmittances measured at the signal and interference wavelength channels in order to assure its validity.

NDIR glucose detection in liquids

A glucose sensor measures glucose molecules in vivo through use of NDIR in which scattering noise is reduced and Absorption Interference Noise (AIN) is suppressed with a reflection technique. Electronics are used to provide an output of glucose concentration glucose in a liquid sampling matrix after it has been determined that a calibration curve is valid after signal processing is used to obtain average ratio values for reflected signal/reference channels and interference/reference channel obtained after a pulsed beam from signal, interference and reference sources is directed at an inclined angle to a normal of a spot of the liquid sampling matrix. The signal, interference and reference sources are each pulsed at a preselected frequency of at least N Hz which is sufficiently fast so that a given molecule of glucose or interfering molecule will not pass in and out of the liquid sampling matrix within the preselected frequency.

For determining concentration of a targeted molecule M in a liquid sample admixed with interfering molecules Mwhich overlap its absorption band, a NDIR reflection sampling technique is used. Besides the signal source, a reference and an interference source are added. M is calculated by electronics which use R(t) from a pulsed signal and reference channel output and a calibration curve which is validated by use of R(t) from a pulsed interference and reference channel output. Signal, interference and reference sources are pulsed at a frequency which is sufficiently fast so that a given molecule of M or Mwill not pass in and out of the liquid sampling matrix within the pulsing frequency.

NDIR reflection sampling in liquids

NDIR is used to determine a concentration of a chosen molecule M in a liquid sample which contains one or more interfering molecules Mwhich absorb radiation at the signal wavelength used in the NDIR process by addition of an interference source. M is calculated by electronics which use R(t) from a pulsed signal and reference channel output and a calibration curve which is validated by use of R(t) from a pulsed interference and reference channel output. Signal, interference and reference sources are pulsed at a frequency which is sufficiently fast so that a given molecule of M or Mwill not pass in and out of the liquid sampling matrix within the pulsing frequency.

NDIR interference control in liquids

A concentration of glucose in a blood sample is determined through use of a signal channel output/reference channel ratio obtained by use of an NDIR absorption technique in which scattering noise attributable to the liquid phase is reduced by alternately and successively pulsing infrared radiation from signal and reference sources which are multiplexed and collimated into a pulsed beam directed through the sample space containing the liquid phase and the pulse frequency is sufficiently fast so that a given molecule of glucose will not pass in and out of the sample space within the pulse frequency.

Reduction of scattering noise when using NDIR with a liquid sample

A concentration of a chosen molecule in a liquid phase in a sample space is determined through use of a signal channel output/reference channel ratio obtained by use of an NDIR absorption technique in which scattering noise attributable to the liquid phase is reduced by alternately and successively pulsing infrared radiation from signal and reference sources which are multiplexed and collimated into a pulsed beam directed through the sample space containing the liquid phase and the pulse frequency is sufficiently fast so that a given molecule of the chosen molecule will not pass in and out of the sample space within the pulse frequency.

A gas sample separated from transformer oil is circulated through an NDIR gas sensor system which obtains an acetylene concentration by calculating a detected acetylene concentration obtained by an absorption biased ('AB') NDIR acetylene gas sensor, calculating a detected carbon dioxide concentration obtained by an AB NDIR carbon dioxide gas sensor, calculating a detected water vapor concentration obtained by an AB NDIR water vapor NDIR gas sensor and then determining the acetylene concentration from the detected acetylene concentration through use of the detected carbon dioxide and water vapor concentrations to compensate for their interference.

Interference-compensating NDIR gas sensor for measuring acetylene

A miner's personal gas alarm can be mounted in a helmet powered by a rechargeable battery for a light or be self-contained. A visual indicator will generate an alarm when the concentration of gas detected by the gas sensor triggers an alarm condition. An audio alarm can also be generated by the alarm condition. The gas sensor is a non-dispersive infrared ('NDIR') gas sensor. When the gas sensor detects methane, the alarm condition is triggered by either an abnormally high rate of increase of methane concentration level or by an elevated concentration of methane that is above approximately 500 ppm and substantially below a lower explosion limit of methane (e.g., approximately 10,000 ppm), and the gas sensor is recalibrated whenever the sample concentration of methane falls below an ambient threshold level of methane.

Methane and water vapor gas sensors integrated into a personal miner's alarm

A differential temperature source methodology for the design of a single beam NDIR gas sensor is advanced. This methodology uses a low and a high amplitude voltage cycle to drive a closely approximated Blackbody source for generating at different times two distinct detector outputs obtained from the same detector equipped the same narrow band pass filter but strategically designed for the detection of only a particular portion of the absorption band for the gas of interest. The ratio of the high amplitude cycle detector output over the low amplitude cycle detector output is used to calibrate such an NDIR gas sensor after it is normalized by a similar ratio when there is no target gas present in the sample chamber.

Growing community of inventors

Goleta, CA, United States of America

Jacob Y Wong