Abstract: An evaluation device for evaluating analog measuring signals of a detector, e.g., an IR detector, includes: an analog/digital converter device for digitally converting the analog measuring signal of the detector or an analog signal derived from the analog measuring signal into a digital measuring signal; a control device for receiving the digital measuring signal; and a subtraction device. The evaluation device receives a first analog measuring signal from a first measurement and stores the digital measuring signal formed from the first analog measuring signal, and also receives a second analog measuring signal from a second measurement. The subtraction device receives the analog measuring signal of the second measurement and an analog comparison signal formed as a function of the stored digital measuring signal of the first measurement, and forms a differential signal.

Abstract: The invention is to provide an inspection apparatus causing interactions of plural times between an object and an electromagnetic wave, thereby enabling inspection with a satisfactory sensitivity even for an object of a trace amount. The inspection apparatus detects information from an object 112 based on a change in an electromagnetic wave transmission state caused by plural times of interactions between the electromagnetic wave and the object 112.

Abstract: A method and system for detecting concealed weapons and explosives by imaging THz scenes using conventional optics and detectors is provided. Photon fields with two different wavelengths can be sent through a chopper and towards a wavelength-selective mirror. A light beam with a wavelength in the visible or IR range is sent toward a visible photon array detector. Similarly, light beams with wavelengths in the THz range can be sent towards a target, which are reflected and/or absorbed by objects in the target. The reflected or transmitted light continues on through an optional filter to remove background light, then into a non-imaging detector. The visible photon array detector can be coupled with the non-imaging detector, which will register an image of the scene that is illuminated by the THz photons.

Abstract: A number of reagent-free infrared spectroscopic diagnostic and analytical methods have been established previously, making use of dry biofluid films. For example, this approach has successfully measured high concentration analytes of serum and urine. However, a number of low concentration diagnostically relevant analytes presently elude detection by infrared spectroscopy. This is due in part to their relatively low concentration and in part to spectral interference by other strongly absorbing constituents. The applicability of the technique would be broadened substantially if it were possible to separate and concentrate, lower concentration analytes, e.g. serum creatinine and urine proteins, from the obscuring presence of relatively high concentration compounds. The invention disclosed achieves this is through microfluidic sample preconditioning based upon laminar fluid diffusion interfaces.

Abstract: A thermal analysis equipment includes a thermal analysis data preservation function that preserves, as thermal analysis data, signals from a temperature sensor and a physical quantity sensor that detect a temperature and a change in physical quantity, respectively, of a sample. An electromagnetic-wave data acquisition control function controls acquisition of electromagnetic wave data in accordance with setting of a trigger to acquire the electromagnetic wave data. An electromagnetic-wave data preservation function preserves the electromagnetic wave data. An electromagnetic-wave data correlation function correlates the preserved electromagnetic wave data to a position on the thermal analysis data when the trigger is set.

Abstract: An imaging system for imaging an object. The imaging system includes a support member adapted to receive the object in an immobilized state. The system also includes first means for imaging the immobilized object in a first imaging mode to capture a first image, and second means for imaging the immobilized object in a second imaging mode, different from the first imaging mode, to capture a second image. The first imaging mode is selected from the group: x-ray mode and radio isotopic mode. The second imaging mode is selected from the group: bright-field mode and dark-field mode. A removable phosphor screen is employed when the first image is captured and not employed when the second image is captured. The phosphor screen is adapted to transduce ionizing radiation to visible light. The phosphor screen is adapted to be removable without moving the immobilized object. The system can further include means for generating a third image comprised of the first and second image.

Abstract: Systems and methods for infrared power control supporting multi-use functionality are presented. In one example, the transmit power level of an infrared (IR) light source on a headset having multiple functional states is controlled based on the headset function state. Infrared power control is used to determine proximity between an infrared source device and an infrared receiver device.

Abstract: Methods of determining thickness and phase of a GST layer on a semiconductor substrate are described using intensity spectra within the infra-red range. In particular, techniques for using certain transmission at certain frequencies are disclosed for faster thickness and phase determination in an in-line or standalone metrology/monitoring system for CMP processes.

Abstract: The invention relates to methods and apparatus for modifying the frequency characteristics of a spatially-dispersed mid-IR spectra for spectroscopy. In a preferred embodiment, sum frequency generation between a frequency-dispersed IR beam and an ultrafast optical pulse generates a spatially-extended optical signal that is collected with a CCD detector.

Abstract: A non-dispersive single beam detection assembly in an infrared gas analyzer. The detection assembly comprises radiation source(s) providing infrared radiation, a measuring chamber, and a physical beam splitter for dividing said radiation beam into a reflected beam portion and a transmitted beam portion, or for combining a reflected beam portion and a transmitted beam portion into said radiation beam. A measuring detector receives one beam portions, and a reference detector receives another beam portion. Alternatively a measuring/reference detector receives both beam portions. Said transmitted beam portion has a first spectral intensity peak at shorter wavelengths with a first peak wavelength, and said reflected beam portion has a second spectral intensity peak at longer wavelengths with a second peak wavelength.

Abstract: An electronic device having one or more sensors is provided. The sensors may include any suitable type of sensor, including for example a proximity sensor, an ambient light sensor, or any other suitable type of sensor that emits or receives radiation (e.g., light waves) from the environment. The electronic device may include openings through which radiation may reach the sensors while keeping the sensors hidden from view. In some embodiments, the sensors may be placed underneath an opening used for an audio receiver such that radiation is piped to the sensors using a light path or a chamfered surface along the opening. In some embodiments, the sensors may be embedded in a screen such that the radiation emitted by the sensors exits the screen instead of being reflected on the screen (e.g., to provide content displays).

Abstract: An image forming apparatus includes an electromagnetic wave radiating portion, an electromagnetic wave detecting portion, a driving portion, a periodical signal generating portion for generating plural periodical signals, a memory portion, a processing portion, and an image forming portion. The driving portion changes the relative positional relationship between an object and the radiating portion. The detecting portion acquires transmitted or reflected wave from the object, as a time-series detection signal. The processing portion executes a process of multiplying the detection signals of the areas of the object with the periodical signals, and a process of adding the multiplied results and causing the memory portion to store the added results.

Abstract: A marking system that allows remote observations of visual and infrared electromagnetic signatures emitted from a distinctive marker panel. A kit employing such panels is particularly suitable for military environments, which, in turn, enhances the survivability of military equipment. The marking system preferably provides a signature in the mid and far infrared and near infrared portions of the electromagnetic spectrum, such that the electromagnetic radiation can be observed by a pilot in an approaching moving object such as a plane, helicopter, or land vehicle that is equipped with a thermal imaging system or light intensifier device, even in adverse environmental conditions. In varying embodiments, the marking system may be used as a landing marker, a bore sight panel, and an identification panel. Utilization of passive infrared material enables use of such marking system when external power is unavailable.

Abstract: A method of identifying and determining the concentrations of multiple species in a gas sample, includes providing a spectrophone assembly having a detector chamber, supplying the gas sample to the detector chamber and simultaneously passing a plurality of radiations of different wavelengths into the detector chamber to produce multiple acoustic resonances of different frequencies. Acoustic resonances in the detector chamber are simultaneously sensed to produce corresponding electrical signals, and the electrical signals are analysed to identify the species present in the gas sample and determine the concentration of each specie.

Abstract: An IR spectroscopic method of determining the presence or absence of metallic material embedded in polymer material including irradiating a surface of said polymer material and collecting at least one spectrum of reflected infrared energy from said surface of said over a spectrum of wavelengths including the near-infrared wherein said metallic material is at least partially absent in a affected condition; performing a multivariate comparison of said at least one spectrum with at least one reference spectrum to determine a change in reflectance of said at least one spectrum with respect to at least one reference spectrum wherein said metallic material is present in an unaffected condition; and, correlating the amount of said change in reflectance with the presence or absence of said metallic material embedded in said polymer material.

Abstract: A device for determination of the surface condition of a roadway includes a light-sensitive sensor to measure a light signal reflected from the surface of the roadway and an analyzer to determine the surface condition of the roadway as a function of the power of the light signal at a first wavelength in the infrared range, at a second wavelength in the infrared range and at least a third wavelength in the infrared range.

Abstract: The present invention is a broadband energy illuminator for creating contrast between the broadband energy emanating from a scene and an individual within the scene. A millimeter wave camera is focused toward the individual to detect millimeter wave frequencies reflected from the scene. As an individual passes through scene the millimeter wave camera detects concealed objects by identifying differences in the millimeter wave energy reflected by the individual's body and a concealed object. The broadband energy illuminator focuses a cold source of broadband energy on the scene thereby enhancing the ability of the millimeter wave camera to distinguish the individual's body from concealed objects. A composite image is generated by a central processing unit and displayed on a monitor showing the concealed object on the individual through optical contrast.

Abstract: Provided are devices and methods for quantifying a surface's cleanliness relative to a contaminant. Such devices and methods may comprising and use a source of interrogating radiation to which the contaminant is responsive, a means for directing the interrogating radiation, a detector, and an analyzer. Radiation emitted from the source is directed by the radiation means toward the surface or a surface cleaner that may hold the contaminant. The detector detects radiation from the surface or the surface cleaner produced in response to the interrogating radiation by the contaminant, e.g., fluorescent or phosphorescent radiation, and generate a corresponding signal that is compared by the analyzer relative to an electronic standard that corresponds to the surface in an acceptably clean state so as to quantify the surface's cleanliness.

Abstract: A spectral acquisition method includes actively processing a sample, such as a an opaque, friable pharmaceutical dosage unit, to expose characteristics of interior portions of the sample, and acquiring spectral information from the interior portions.

Abstract: Disclosed is a method and apparatus for detecting the type of anesthetic gas. The method comprises the steps of: generating a light with a plurality of wavelengths, the light being able to be separated to a plurality of light beams whose central frequencies correspond to the plurality of wavelengths; passing said light through a gas chamber, wherein, the gas chamber being filled with said anesthetic gas, said anesthetic gas having absorption characteristic with respect to said plurality of light beams; detecting the light intensity of the attenuated light beams transmitted from the gas chamber respectively, to obtain the relative absorption characteristic of said attenuated light beams, which attenuated light beams having been absorbed by said anesthetic gas; and determining the type of said anesthetic gas based on the relative absorption characteristic between said attenuated light beams.

Abstract: The invention is directed to a night vision system that has an illuminator that transmits light towards a target using light outside the visible spectrum. A receive optics focuses an image on a charge coupled device. This system with an ultraviolet illuminator allows the night vision system to view images beyond 2500 meters, while present systems are limited to around 800 meters. The illuminator is generally a high peak power pulsed light source. A processor uses frame addition techniques to increase the captured light and may use binning techniques to increase the signal to noise ratio. The system may use multiple illuminators and capture images at a number of different wavelengths.

Abstract: A light emission section spread-spectrum modulates a base band signal at a chip frequency f to thereby generate a primary modulated signal, modulates the primary modulated signal at a frequency 2f to thereby generate a secondary modulated signal, and emits a near-infrared light beam having a specific wavelength into a living organism on the basis of the secondary modulated signal. A light detection section receives a reflected light beam from the interior of the living organism in an effective detection band 2f, converts it to an electrical detection signal, and converts the detection signal to a digital signal at a sampling frequency 4f. The light detection section then demodulates the digital signal at the frequency 2f to thereby generate a primary demodulated signal, and demodulates the primary demodulated signal through spectrum despreading to thereby generate a secondary demodulated signal. Thus, a biological information signal representing biological information is output.

Abstract: An inspection apparatus includes a terahertz wave detection portion, a waveform shaping portion configured to shape a first answer signal with respect to a terahertz wave by using a signal acquired in the above-described terahertz wave detection portion, a measurement condition acquisition portion configured to acquire a first measurement condition, an answer signal storage portion configured to store second answer signals corresponding to measurement conditions, a selection portion configured to select the above-described second answer signal from the above-described answer signal storage portion, and a signal processing portion configured to conduct deconvolution with respect to the above-described first answer signal on the basis of the above-described second answer signal.

Abstract: A method and system for imaging an object includes transmitting distinguishable electromagnetic waves from a plurality of radiators of an antenna array, wherein each of the distinguishable electromagnetic waves is distinguishable from others by a detector. Each of the radiators transmits radiation comprising a different distinguishable electromagnetic wave. The method also includes imaging at least a portion of the antenna array onto a targeted object, wherein each image area of a plurality of image areas on the targeted object corresponds to an image of a respective radiator of the antenna array, and detecting a plurality of resultant electromagnetic waves, wherein the resultant electromagnetic waves are transmitted, scattered, or reflected by respective image areas on the targeted object in response to each of the respective image areas being illuminated by the radiation transmitted by the respective radiator of the source array.

Abstract: A technique and apparatus for detection of infrared radiation emitted from a taggant material sample following the excitation of the sample are described. The decay time of the radiation is a function of the particular taggant being used and so, if the decay characteristic or signature is accurately measured, the particular taggant can be accurately identified. The apparatus comprises an electronic controller (10), a pair (12) of illuminating light-emitting diodes, a photo-detector (14), a first amplifier (16), a three-way sampling switch (18), filter/stores (20)(a-c), second amplifiers (22)(a-c) and an output display (26). The infrared emission is excited by repeatedly illuminating the material for a period of microseconds every few milliseconds using a very intense source of infrared light. This light is supplied by the pair of 940 nm, light-emitting diodes (12). Once this light source has been turned off, the sample continues radiating infrared light for a few milliseconds.

Abstract: A microwave or terahertz and neutron radiation type detector, which uses an orbitron as a radiation source. The detector may have a polarity switching apparatus to enable the orbitron to selectively change from between short wave to neutron emission functions. A highly compact and lightweight identifier of explosives and other chemicals, which may be so small and light as to be hand held, and which is effective at stand-off distances, is thereby provided.

Abstract: A method of creating signage visible by infrared cameras and infrared weapon sights is provided. Particular application is made to the calibration of infrared weapon sights. An improved calibration target and method is developed.

Abstract: A light emission section spread-spectrum modulates a base band signal at a chip frequency f to thereby generate a primary modulated signal, modulates the primary modulated signal at a frequency 2f to thereby generate a secondary modulated signal, and emits a near-infrared light beam having a specific wavelength into a living organism on the basis of the secondary modulated signal. A light detection section receives a reflected light beam from the interior of the living organism in an effective detection band 2f, converts it to an electrical detection signal, and converts the detection signal to a digital signal at a sampling frequency 4f. The light detection section then demodulates the digital signal at the frequency 2f to thereby generate a primary demodulated signal, and demodulates the primary demodulated signal through spectrum despreading to thereby generate a secondary demodulated signal. Thus, a biological information signal representing biological information is output.

Abstract: A method and system for detecting concealed weapons and explosives by imaging THz scenes using conventional optics and detectors is provided. Photon fields with two different wavelengths can be sent through a chopper and towards a wavelength-selective mirror. A light beam with a wavelength in the visible or IR range is sent toward a visible photon array detector. Similarly, light beams with wavelengths in the THz range can be sent towards a target, which are reflected and/or absorbed by objects in the target. The reflected or transmitted light continues on through an optional filter to remove background light, then into a non-imaging detector. The visible photon array detector can be coupled with the non-imaging detector, which will register an image of the scene that is illuminated by the THz photons.

Abstract: In a terahertz radiation detection system, an array of harmonic transmitters/receivers can be scanned across a field of view. By using an unbalanced pair of Schottky diodes in the mixer of a heterodyne receiver, the receiver can be converted to a transmitter, generating terahertz radiation at even harmonics of the local oscillator. By using local oscillators of different frequencies in the transmitter and a receiver, the receiver can detect the generated radiation. In alternative arrangements, the local oscillator of the transmitter might have the same frequency as that of the receiver but be modulated, either directly or simply as a result of the transmitter being scanned across the field of view. If modulated directly, it might be amplitude or frequency modulation, these having different advantages. A receiver can be switched between acting as a transmitter and as a receiver by turning on and off an electrical bias to the Schottky diode pair.

Abstract: The apparatus is a miniature assembly which detects very low power infrared radiation and produces an electronic signal. The incoming infrared is combined in a wavelength multiplexer with high energy light from a laser chip and passed through an upconversion crystal (a nonlinear optical crystal) in which their frequencies are added together. The higher frequency, lower wavelength, light is then directed to a miniature blue sensitive photomultiplier tube that generates an electrical signal. A thermoelectric cooler is used to control the temperature of the laser chip, and the entire device is assembled into a package which is approximately the size of a cigarette pack.

Abstract: A method and apparatus is disclosed for inspection of molded closures that would measure specific parameters of the closure on an on-line basis as they are ejected from an associated compression molding apparatus. Measuring specific parameters of the closure on an on-line basis identifies problems with specific tool sets, sub-systems, and process settings of the molding apparatus, thus substantially reducing the amount of scrap that is produced.

Abstract: A device for analyzing a materials library includes at least one radiation source for electromagnetic radiation, which is positioned in front of the materials library, and at least two flat detectors operating in parallel, which are operable using high-sensitivity resolution and of which one is sensitive to electromagnetic radiation of a first wavelength range and the other is sensitive to electromagnetic radiation of a second wavelength range. Moreover, a method for analyzing a materials library in which the materials library is simultaneously tested using at least two methods in which electromagnetic radiation of different wavelength ranges is used. The beam is split behind the materials library as a function of wavelength and is deflected in the direction of at least two flat sensors operating using high-sensitivity resolution.

Abstract: The present invention relates to an apparatus for analyzing cells in real-time which incorporates a wavelength-tunable light source/infrared ray (IR) sensor and can be used to observe and analyze the IR-related characteristics of adherent cells or non-adherent cells. The Apparatus for analyzing cells in real-time in accordance with the present invention can be used to quantify specific materials in a cell and measure the metabolism of a cell. In addition, the apparatus for analyzing cells in real-time in accordance with the present invention can be configured to have a visible light microscope coupled thereto, and in this configuration, it can be used to locate a cell of interest.

Abstract: A method and system for imaging an object includes transmitting distinguishable electromagnetic waves from a plurality of radiators of an antenna array, wherein each of the distinguishable electromagnetic waves is distinguishable from others by a detector. Each of the radiators transmits radiation comprising a different distinguishable electromagnetic wave. The method also includes imaging at least a portion of the antenna array onto a targeted object, wherein each image area of a plurality of image areas on the targeted object corresponds to an image of a respective radiator of the antenna array, and detecting a plurality of resultant electromagnetic waves, wherein the resultant electromagnetic waves are transmitted, scattered, or reflected by respective image areas on the targeted object in response to each of the respective image areas being illuminated by the radiation transmitted by the respective radiator of the source array.

Abstract: Methods and apparatus for measuring a phase fraction of a flow stream are disclosed. An infrared phase fraction meter includes a light source for emitting into a flow stream infrared radiation that includes first and second wavelength bands. The first wavelength band substantially transmits through first and second phases of the flow stream and is substantially absorbed by a third phase. In contrast, the second wavelength band is substantially absorbed by the second phase relative to the first and third phases. One or more detectors simultaneously detect attenuation of the first and second wavelength bands upon the infrared radiation passing through at least a portion of the flow stream, and a phase fraction of the second phase is determined based on the attenuation. As an example, the first, second and third phases are gas, water and oil, respectively, produced from a well.

Abstract: A temperature sensing component enables accurate in situ temperature measurement. The temperature sensing component is disposed within the process chamber. The temperature sensing component has a cavity, in which a transparent cover is disposed over an opening of the cavity. A material is disposed within the cavity of the temperature sensing component, and a sensor is configured to sense a phase change of the material through the transparent cover.

Abstract: A lightweight, low-cost, and highly sensitive aerosol sensor measures aerosol concentrations remotely. A fiber laser sends pulses outward toward the target area from a carbon-fiber telescope using ultra-lightweight optical elements. Light is received back in the same telescope or in another similar telescope depending on the aerosol concentration or other contents of the atmosphere. The sensor is lightweight, low-cost and has high performance. The system also measures aerosol profiles over a hemispherical volume to produce a three-dimensional measurement within the range of the laser.

Abstract: A fire detector and method for generating an alarm signal in response to a fire uses an NDIR sensor to generate a detector signal based upon one or more absorption bands selected from the 15.1? absorption band of CO2, the 6.27? absorption band of H2O and the 4.67? absorption band for CO and generates an alarm signal when a signal processor receives the detector signal and a preselected criterion is met that is indicative of the onset of a fire based upon an analysis of the detector signal using a detection algorithm that relies upon a trending pattern of the detector signal such as recognizing a substantial drop in the detector signal strength. The fire detector has a waveguide sample chamber (which can be of a re-entrant design) with at least one opening covered by a thin filtering membrane and a heat exchanger thermally connected to the sample chamber with at least one opening covered by another thin filtering membrane.

Abstract: Methods for determining corrosion products on a substrate are disclosed. In one embodiment, a non-destructive method for determining an amount of corrosion product on a metallic substrate includes non-destructively determining a value Ia of infrared energy absorbed in a corrosion product on a metallic substrate; and correlating the value Ia of the infrared energy absorbed to an amount of the corrosion product.

Abstract: A fixed visible input and tunable visible input are directed to a location on a surface to be interrogated. The fixed visible input and the tunable visible inputs are aligned so that their surface locations of optical illumination overlap on the interrogated location. An output wavelength discriminator receives the reflected difference-frequency generated on the interrogated location. The output wavelength discriminator is substantially non-transmissive at frequencies higher than the difference-frequency, but substantially transmissive at the difference-frequency of the fixed visible input and the tunable visible input. Signal collection optics receives an output of the output wavelength discriminator and directs the propagation of the output thereof so that a collected optical light signal is formed after propagation through the signal collection optics. The collected optical light signal is converted to an electronic signal.

Abstract: There is disclosed an apparatus comprising: a terahertz wave generation device which generates a terahertz wave; a terahertz wave irradiation device which irradiates an object to be inspected with the terahertz wave; and a scattering intensity detection device which cuts a rectilinear wave of the terahertz wave which has passed through the object to be inspected and which detects an intensity of a scattered wave, and a scattered material such as powder or foam contained in an envelope, a capsule, a container or the like is detected in a non-destructive manner without unsealing the envelope or the like.

Abstract: Rays incident upon a plurality of detection plates arranged along a normal direction are detected. A distance between the ray and the ray source is estimated based on the number of counted rays detected by each detection plate, and each interval distance of the detection plates. Moreover, the direction of the source of the ray is estimated based on each image obtained from each detection plate.

Abstract: A level sensor for a lithographic projection apparatus includes a light source configured to direct light onto a substrate to be measured, a detector configured to detect light reflected from the substrate, and a processor configured to calculate a difference between measurements made with the filter in the first configuration and in the second configuration. The sensor is adjustable between a first configuration, in which the light is given a first property, and a second configuration, in which the light is given a second property. The sensor may include a polarizing filter, such that the first and second properties are different polarization states.

Abstract: A portable radiation detector using a high-purity germanium crystal as the sensing device. The crystal is fabricated such that it exhibits a length to width ratio greater than 1:1 and is oriented within the detector to receive radiation along the width of said crystal. The crystal is located within a container pressurized with ultra-pure nitrogen, and the container is located within a cryostat under vacuum.

Abstract: Stand-alone multiple gas analysis apparatus, of relatively small physical size, integrates one or more supplemental sensors, such as a self-heating, amperometric, limiting current-type oxygen sensor and/or a titania nanotube-type hydrogen sensor, into the sampling cell gas flow components of an FT-IR gas analyzer. The apparatus enables simultaneous quantitative concentration measurements of infrared-active gases and of infrared-inactive atomic species and homonuclear diatomic molecules, such as of oxygen and hydrogen.

Abstract: A method of creating an image of a radiation source includes detecting radiation associated with a first location of the radiation source. Data substantially corresponding to the radiation associated with the first location is processed to provide a first value. The first value is employed to generate a first portion of the image associated with the first location. Radiation associated with a second location of the radiation source is detected. Data substantially corresponding to the radiation associated with second location is processed to provide a second value. The second value is employed to generate a second portion of the image associated with the second location.

Abstract: Embodiments of the invention may reduce timing and spatial distortion in Picosecond Imaging and Circuit Analysis (PICA). In one embodiment, a method of determining distortion in a circuit image comprises: defining potential photon emission areas in the circuit image using a layout database, determining ideal photon emissions over the potential photon emission areas, measuring photon emissions for the potential photon emission areas, comparing the ideal photon emission with the measured photon emissions, and producing a mathematical model that predicts the amount of spatial distortion over the potential photon emission area.

Abstract: An optical measurement system is presented that offers precision on-line monitoring of the quality of steam. Multiple wavelengths of radiant energy are passed through the steam from an emitter to a detector. By comparing the amount of radiant energy absorbed by the flow of steam for each wavelength, a highly accurate measurement of the steam quality can be determined on a continuous basis in real-time. In an embodiment of the present invention, the emitter, comprises three separate radiant energy sources for transmitting specific wavelengths of radiant energy through the steam. In a further embodiment, the wavelengths of radiant energy are combined into a single beam of radiant energy for transmission through the steam using time or wavelength division multiplexing. In yet a further embodiment, the single beam of radiant energy is transmitted using specialized optical elements.

Abstract: A method and apparatus for monitoring the flue gases of a furnace combustion process is disclosed. A by-pass circuit that communicates a sample of flue gases to be monitored from a furnace, through a measurement chamber and back to the furnace or furnace exhaust duct is provided. The by-pass circuit has a gas sampling probe with a fume inlet opening, the probe being positioned for withdrawing the sample to be monitored and transmitting it through the by-pass circuit. A measurement device is positioned in the measurement chamber and comprises an in situ optical device which provides real-time measurement of targeted flue gas species concentrations.