Abstract: Spectroscopic system and spectrometers including an optical bandpass filter unit having a plurality of bandpass regions and a spatial encoding unit for encoding discrete frequencies of light passing through the optical filter. The incorporation of the encoding unit allows the spectrometer system to use a detector having one or a small number of elements, rather than using a more expensive detector array typically used with filter-based spectrometers. The system can also include an integrating chamber that collects the light that is not transmitted through the bandpass filter unit, and redirects this light to strike the filter unit again, resulting in a significant increase in the optical power passing through the filter. The integrating chamber maximizes the return of the reflected light to the filter assembly and minimizes optical losses. The integrating chamber may be an orthogonal design to preserve the optical geometric characteristics of the light entering the chamber.

Abstract: In a method of controlling a metallic layer etching process for fabricating a semiconductor device or a liquid crystal display device, the composition of the etchant used in etching the metallic layer is first analyzed with the NIR spectrometer. The state of the etchant is then determined by comparing the analyzed composition with the reference composition. In case the life span of the etchant comes to an end, the etchant is replaced with a new etchant. By contrast, in case the life span of the etchant is left over, the etchant is delivered to the next metallic layer etching process. This analysis technique may be applied to the etchant regenerating process in a similar way.

Abstract: A radiation detector 10 has a base 12 and a window 16 that define a vacuum chamber 20. Within the vacuum chamber 20 is a temperature controlled filter 32 and a focal plane array (FPA) 22 defining a gap h therebetween. The filter 32 is heat sunk to a readout integrated circuit (ROIC) 24 and thermoelectric elements 28 to inhibit heat transfer from non-scene sources 38, 40 to the FPA 22. The temperature controlled filter 32 may also incorporate a bandpass filter to reflect all sources of radiation not within the desired wavelength region of interest. The temperature controlled filter 32 is maintained at substantially the same temperature as the FPA 22.

Abstract: The present invention relates to an instrument for measuring in relatively short periods of time concentrations of constituents in optically dense materials using the spectra near infrared radiation transmitted through thick samples of the material while the material is either stationary or flowing. The invention uses a broadband incandescent intensity stabilized light source combined with collimating optics to transmit a parallel beam of light through the material under test. The light transmitted through the material is then collected by a focusing lens and imaged onto a rectangular entrance slit of a special purpose spectrometer. This spectrometer has no moving parts and employs a fixed diffraction grating to physically spread the image of the entrance slit into a continuous range of wavelengths. A portion of the diffracted slit images covering the selected portion of the near infrared range is focused onto an array of individual rectangular photodiodes.

Abstract: Mirror elements are selectively interposable in the beam paths in a dual aperture microspectrometer system to selectively bypass the aperture element in transmission or reflection modes to increase optical throughput and field of view. The system may be operated in a dual aperture transmission mode or reflection mode and in modes in which the aperture is bypassed before or after the infrared beam reaches the sample. The system may be operated to bypass the aperture both before and after the sample, which may be utilized with an array detector having multiple detector elements in which an image of the sample is formed on the array detector.

Abstract: A compact spectrometer operable in a wavelength range of 4.5 or more microns includes an entrance slit, a collimating mirror, a grating, a focusing mirror and a first focal plane. At least some radiation passing through the slit follows an optical path in which at least some radiation passing through the slit is reflected by the collimating mirror onto the grating, which in turn reflects at least some radiation onto the focusing mirror, which in turn reflects and focuses at least some radiation at a first focal plane and onto the two-dimensional array of detectors. Each column in the two-dimensional array of detectors corresponds to a wavelength in the 4.5 or more micron range. The two-dimensional array includes a plurality of columns that collectively correspond to wavelengths spanning the 4.5 or more micron range, and each adjacent pair of columns in the two-dimensional array of detectors corresponds to two wavelengths that differ by an equal amount.

Abstract: An infrared spectrometer system with automated tablet sampling includes an infrared spectrometer providing a modulated output beam to a sample position, and reflected and transmitted light detectors. A tablet holding wheel is mounted to advance multiple tablets one at a time to the sample position. The tablet holding wheel includes a tablet wheel base having a plurality of transmission openings therein in a circular pattern around a central axis of the base, grippers adjacent to each of the transmission openings that are movable inwardly and outwardly, and a cam ring mounted to and rotatable with respect to the tablet wheel base, the cam ring being operatively engaged with the grippers to move the grippers outwardly and inwardly to engage and hold tablets over the transmission openings.

Abstract: A compact imaging spectrometer comprising an entrance slit for directing light, a first mirror that receives said light and reflects said light, an immersive diffraction grating that diffracts said light, a second mirror that focuses said light, and a detector array that receives said focused light. The compact imaging spectrometer can be utilized for remote sensing imaging spectrometers where size and weight are of primary importance.

Abstract: Diffraction which is used to measure features on a substrate layer is disclosed. A substrate, such as a mask structure for microelectronics or a semiconductor substrate with reflective or transmissive features, is irradiated by a source emitting radiation of known wavelength at an angle of incidence relative to the substrate. Given a known pitch, the width of the features themselves is measured by analyzing a diffraction pattern by computer after capturing characteristics of the pattern with a detector.

Abstract: A chemical imaging system is provided which uses a near infrared radiation microscope. The system includes an illumination source which illuminates an area of a sample using light in the near infrared radiation wavelength and light in the visible wavelength. A multitude of spatially resolved spectra of transmitted, reflected, emitted or scattered near infrared wavelength radiation light from the illuminated area of the sample is collected and a collimated beam is produced therefrom. A near infrared imaging spectrometer is provided for selecting a near infrared radiation image of the collimated beam. The filtered images are collected by a detector for further processing. The visible wavelength light from the illuminated area of the sample is simultaneously detected providing for the simultaneous visible and near infrared chemical imaging analysis of the sample. Two efficient means for performing three dimensional near infrared chemical imaging microscopy are provided.

Abstract: A method of determining the analyte concentration of a test sample is described. A temperature gradient is introduced in the test sample and infrared radiation detectors measure radiation at selected analyte absorbance peak and reference wavelengths. Reference and analytical signals are detected. In the presence of the selected analyte, parameter differences between reference and analytical signals are detectable. These parameter differences, having a relationship to analyte concentration, are measured, correlated, and processed to determine analyte concentration in the test sample. Accuracy is enhanced by inducing a periodically modulated temperature gradient in the test sample. The analytical and reference signals may be measured continuously and the parameter difference integrated over the measurement period to determine analyte concentration.

Abstract: An apparatus for verifying the identity of a dispensed pharmaceutical comprises an analysis unit adapted to determine a property of the dispensed pharmaceutical, an input device adapted to receive predetermined identifying information corresponding to the dispensed pharmaceutical, and a comparison unit adapted to compare the determined property of the dispensed pharmaceutical with the predetermined identifying information. In addition, a method of verifying a prescription, wherein the prescription comprises a pharmaceutical compound, comprises associating the prescription with a unique identifier, storing the unique identifier, determining the identity of the pharmaceutical compound, and comparing the identity of the pharmaceutical compound with the unique identifier.

Abstract: The present invention is a sample holder for spectrum measurement settable in a measuring chamber of a spectrophotometer and being used for measuring a spectrum of a liquid sample, which comprises a holding block (11) having a hole (111) and a light introducing path (112) being provided crosswise, and a light introducing path position adjusting means (12) being located under the holding block (11), said the light introducing path position adjusting means (12) comprising a light introducing path horizontal direction position adjusting means (12-1) and/or a light introducing path vertical direction position adjusting means (12-2), for adjusting so as to the irradiation light is introduced into the liquid sample by aligning a position of the light introducing path (112) with a propagating route of the irradiation light for spectrum measurement, said the holding block (11) further comprising a device for controlling a temperature of said liquid sample.

Abstract: Electronically agile optical filtering modules for equalizing light propagation differences in at least two spaced optical beam pathways in the modules. The modules use optical polarization rotation devices that may include acousto-optic tunable filter (AOTF) devices, liquid crystal devices, and magneto-optic devices. Such devices may be subject to polarization dispersion losses (PDL) and polarization mode dispersion (PMD) that may be different for when light travel along different light paths through the device. By redirecting light beams back along a different bi-directional path through the devices which may exhibit non-uniform performance across orthogonal polarizations, PDL and PMD may be reduced.

Abstract: An imaging spectrometer apparatus comprising an entrance slit for directing light, a light means for receiving the light and directing the light, a grating that receives the light from the light means and defracts the light back onto the light means which focuses the light, and a detector that receives the focused light. In one embodiment the light means is a rotationally symmetric ZNSE aspheric lens. In another embodiment the light means comprises two ZNSE aspheric lenses that are coaxial. In another embodiment the light means comprises an aspheric mirror and a ZNSE aspheric lens.

Abstract: A mid-IR spectrometer attachment performs reflection spectroscopy measurements using commercially available infinity corrected light microscopes without degrading the microscope's performance. The mid-IR spectrometer attachment, which is mounted to and supported by the visible light microscope, introduces infrared radiation into the optical path of the microscope. Radiation from the mid-IR spectrometer source is directed by a trichroic radiation director to a mid-IR objective lens affixed to the microscope nosepiece. The objective lens focuses the radiation on to a subject sample surface in order to acquire either internally or externally reflected infrared spectra by subsequently directing the sample encoded reflected mid-infrared radiation to the radiation director and then to a mid-infrared radiation detection system.

Abstract: A single vane shutter flag is asynchronously controlled so that a measuring system light source is interrupted for a minimum necessary amount of time for standardization/calibration and normalization of InGaAs system detectors. Source/detector hemispheres or serially connected randomly oriented fiber bundles homogenize light passing to the detectors. Light source testing is performed by measuring spectral power distributions at a plurality of light source power levels and comparing the measurements to baseline characteristics established for the light source. Calibration sample life is extended indefinitely by controlling the shutter flag to block source light except for short calibration time periods during which standard light levels are provided.

Abstract: A method of processing data from at least one spectrophotometer characterized by the steps of transferring the data from the spectrophotometer to a control processing unit, processing the data at the central processing unit, and transferring the processed data to the output device.

Abstract: A method and apparatus of determining the analyte concentration of a test sample is described. A temperature gradient is introduced into the test sample and infrared radiation detectors measure radiation at selected analyte absorbance peak and reference wavelengths. The modulation of the temperature gradient is controlled by a surface temperature modulation. A transfer function is determined that relates the surface temperature modulation to the modulation of the measured infrared radiation. Reference and analytical signals are detected. In the presence of the selected analyte, phase and magnitude differences in the transfer function are detected. These phase and magnitude differences, having a relationship to analyte concentration, are measured, correlated and processed to determine analyte concentration in the sample.

Abstract: The present invention provides a method of calibrating a spectroscopic device for providing a non-invasive measurement of an analyte level in a sample. The method comprises the steps of: (a) providing a plurality of calibration algorithms; (b) taking a set of non-invasive measurements on said sample with said spectroscopic device; (c) calculating a predicted set of analyte levels for each of the calibration algorithms in response to the set of non-invasive measurements, each of the predicted sets of analyte levels being characterized by a variability range, a slope, an R2 (a square of the correlation between said set of non-invasive measurements and said predicted set of analyte levels), and a standard error of prediction; and (d) selecting an appropriate calibration algorithm by using a suitability score based on the variability range, the slope, the R2 an the standard error of prediction for each of the predicted sets of analyte levels.

Abstract: A thin film analyzer capable of static and dynamic measurements is disclosed. The apparatus collects and analyzes spectral reflectance data as a function of time. It is especially useful for measuring the changing thickness of a transparent, organic thin film as it is dissolved by a solvent. The measurements can be made with small quantities of solvent, on the order of one milliliter, in small, localized areas on a coated substrate, thereby allowing multiple, independent measurements on each substrate with minimal consumption of solvent.

Abstract: An optic device with a variable operating mode comprises a micromirror which can be obscured by means of an electrostatically controlled microshutter. In the operating condition of the microshutter, the petal of this adheres over a substrate to allow a beam of light to reach the mirror. In the condition at rest, the petal is curled up and one of its surfaces receives the beam of light and reflects it in all directions, at the same time preventing this from reaching the mirror.

Abstract: A process for detecting low levels of a predetermined quality trait present in an inhomogeneously distributed particulate substrate involving the steps of: (a) providing a particulate substrate to be analyzed; (b) providing a spectrometer with an electromagnetic detector capable of performing spectroscopic measurements with electromagnetic radiation; (c) providing a rotatable sample holder having a transparent area through which electromagnetic radiation may pass; (d) providing a tumbling member located within the rotatable sample holder for tumbling the particulate substrate contained therein; (e) introducing the particulate substrate into the rotatable sample holder; (f) simultaneously rotating and tumbling the particulate substrate contained within the rotatable sample holder; and (g) activating the spectrometer, thereby illuminating the particulate substrate contained within the rotatable sample holder with electromagnetic radiation.

Abstract: It is an object of the present invention to provide a data acquiring method in an infrared imaging apparatus comprising an FTIR device of a continuous scan type for detecting a signal by a multi-element detector. A method of acquiring data from a multi-element detector in an infrared imaging apparatus comprising the steps of scanning each element of the multi-element detector in order synchronously with a sampling signal (12) generated by a reference signal (10) of an interferometer and repeating a series of scanning operations after completely scanning all the elements, thereby carrying out scan, shifting a starting point of sampling in next scan by one element from the starting point of the previous scan, thereby carrying out the same scanning, and repeating the scan at the number of times corresponding to the number of all the elements and then extracting data for each element from storing sampling data, thereby acquiring a data sequence of all the sampling points for each element.

Abstract: A programmable substance detector includes a light source, a sample cell, a programmable diffraction grating positioned to receive light from the light source and to direct diffracted light to the sample cell, and a detector associated with the cell to detect a match between a characteristic of the diffracted light and a corresponding characteristic of a substance within the cell.

Abstract: An absorption spectroscopy apparatus having a fluid inlet and a fluid outlet. The apparatus includes a sample cell including an axis, a side wall having at least one curved reflective surface arrayed about the axis and facing inwardly with respect to the cell such that a beam of energy directed against a predetermined location on the reflective surface is reflected back and forth off the reflective surface and remains in substantially the same plane while inside the cell, and at least one port in the sidewall. The apparatus also includes at least one source/detector reflector having a curved profile in a plane extending perpendicular to the axis of the cell. The reflector is positioned with respect to the port of the cell to reflect energy through the port of the cell and against the predetermined location on the reflective surface of the side wall of the cell.

Abstract: Disclosed is a FT-IR spectroscopy method for the determination of the wax precipitation temperature, and the estimation of the amount of precipitated solid wax material (both crystalline and amorphous) present in a liquid hydrocarbon, such as a petroleum crude oil.

Abstract: The utilization of the sample holder of this invention in infrared spectroscopy overcomes some of the major problems typically encountered with sample holders used in traditional techniques. More specifically, the utilization of the sample holder of this invention eliminates interference fringes typically encountered with films which are prepared from the sample. Traditional sample preparation is frequently a highly labor intensive, multi-step process. The present invention offers a significant advance in the state of sample preparation by virtue of being a simple and robust technique requiring relatively little labor in a single, easy step. Sometimes there is a desire to procure the infrared spectrum of samples that are not film forming. The sample holder of the present invention can be used equally well with samples that do not form solid films, such as low molecular weight crystalline materials, oils and amorphous solid materials.

Abstract: The invention is concerned with a material processing apparatus, e.g. a dryer such as a fluid bed dryer, for processing material, e.g. pharmaceuticals, in a compartment (12) having a wall (10). The wall has a window for transmitting radiation from an infrared spectrometer (30) into the dryer and for transmitting radiation from the material to the spectrometer. The spectrometer (30) can analyse the radiation transmitted from the material to measure a property of the material within the compartment, e.g. its moisture content. The radiation-transmitting element (28) is present in a moveable body (24), e.g. a sphere, that can be moved to bring the element (28) into a second position (31) in which the element is in contact with a duct (40) through which fluid can be passed to clean the element (28). In addition, a wiper member (34) may be provided that wipes the element (28) as it passes over it as the moveable body (26) is moved into the second position.

Abstract: A method and a device for the analysis of products in the form of a capsule, and of empty capsules, by means of NIR reflection spectroscopy are provided wherein the capsule is rotated around at least one axis during the recording of the reflection spectrum. Means for rotating the capsule are also provided.

Abstract: An apparatus (1) including two plates (3, 4) which can be rotated in relation to each other and between which the rheological properties of a test substance (6) disposed in an intervening area (5) can be determined. At least one of the plates (3) is provided with a light inlet (2) sealed by a body (8, 10) in order to carry out an optical measurement method, e.g., infrared spectroscopy, enabling other characteristics of the test substance to be determined simultaneously. The body (8, 10) is light permeable at least in the infrared spectrum, and on its side facing the intervening area (5), the body (8, 10) terminates in a flush contour relative to the to the plate (3) in which it is provided so that undesirable interactions which might affect the measurement of the rheological properties of the test substance (6) are reliably excluded.

Abstract: A flame detection apparatus has a focused array based sensor which is responsive to radiation having a predefined wavelength for generating an image of the infrared radiation emitted within a monitored region, and means for measuring the spectral ratio of the intensity of radiation having a first wavelength emitted within the monitored region to the intensity of radiation having a second wavelength emitted within the monitored region. Processing means analyzes the output of the focused array based sensor and the spectral ratio measuring means for responses indicative of the presence of a flame within the monitored region.

Abstract: Ultrathin silicon oxide films thermally grown on Si(100) are characterized with Mirror-Enhanced Polarized Reflectance Fourier Transform Infrared spectroscopy (MEPR-FTIR). MEPR-FTIR is proposed to effectively probe properties of ultra-thin films. Using a mirror and a polarizer, MEPR-FTIR overcomes the difficulty of weak IR intensities normally encountered in ultrathin gate dielectrics such as SiO2 and the intensity of the silicon oxide longitudinal optical (LO) mode is found to increase by a factor of about 20. Therefore, FTIR spectrometers with sensitivity down to 0.01% may allow even sub-monolayer probing of silicon oxide on Si substrates.

Abstract: An infrared gas analyzer includes an infrared source for emitting infrared energy, a sample cell for gases to be analyzed in the path of infrared energy emitted by the source and an assembly having first and second detectors also in the path of infrared energy and a third detector out of the path of infrared energy, mounted within the assembly and in close thermal proximity to each other and being responsive to impinging infrared energy to produce an electrical response. All detectors are sandwiched between a base and a single window that overlies them. The analyzer further includes a narrow band filter corresponding to an absorption wavelength band for a gas of interest and a narrow band reference filter corresponding to a reference wavelength band. Each of the narrow band filters are positioned outside the assembly and between the assembly and the source in the path of infrared energy.

Abstract: A method for segregating qualities of an agricultural product during processing of the product comprises the step of setting a desired range of a measurement value (2). The measurement value represents a property of the product and defines a first quality of the product for which the measurement value is inside the range and a second quality of the product for which the measurement value is outside the range. The method further comprises the step of analyzing (4) the quality of the product that is being processed. The step of analyzing comprises the steps of continuously extracting samples of the product (4a), irradiating each sample by electromagnetic radiation (4d), spatially separating electromagnetic radiation of different wavelengths (4e), and detecting electromagnetic radiation emitted from the sample (4f). The step of detecting produces intensity signals indicative of detected electromagnetic radiation of different wavelengths.

Abstract: A robust, compact spectrometer apparatus for determining respective concentrations or partial pressures of multiple gases in a gas sample with single as well as multiple and even overlapping, absorption or emission spectra that span a wide spectral range.

Abstract: Apparatus and method for in situ measurements of at least one property of a liquid contained within a vessel.

Abstract: A chemical imaging system is provided which uses a near infrared radiation microscope. The system includes an illumination source which illuminates an area of a sample using light in the near infrared radiation wavelength and light in the visible wavelength. A multitude of spatially resolved spectra of transmitted, reflected, emitted or scattered near infrared wavelength radiation light from the illuminated area of the sample is collected and a collimated beam is produced therefrom. A near infrared imaging spectrometer is provided for selecting a near infrared radiation image of the collimated beam. The filtered images are collected by a detector for further processing. The visible wavelength light from the illuminated area of the sample is simultaneously detected providing for the simultaneous visible and near infrared chemical imaging analysis of the sample. Two efficient means for performing three dimensional near infrared chemical imaging microscopy are provided.

Abstract: A micro-channel plate (MCP) detector system (30) comprising a MCP detector, a data acquisition unit (20), wherein the detector comprises a first and a second MCP electron multiplier (12, 14), one or more anodes (16) connected to the data acquisition unit (20) and a gate electrode (32) disposed between the first and the second MCP electron multiplier (12, 14), wherein the detector system further comprises a data storage unit (36) and a gain control unit (34) which is connected to the gate electrode (32) and to the data storage unit (36), wherein a pilot spectrum is stored in the data storage unit (36), and wherein the gain control unit (34) is arranged to read the pilot spectrum from the data storage unit (36), and to control the potential on the gain electrode (32) as a function of m/z or time in response to said pilot spectrum, such that the transmission of electrons to the second MCP electron multiplier (14) is lowered when abundant protein ions appear, whereby a high sensitivity is maintained during the re

Abstract: An apparatus for verifying the identity of a dispensed pharmaceutical comprises an analysis unit adapted to determine a property of the dispensed pharmaceutical, an input device adapted to receive predetermined identifying information corresponding to the dispensed pharmaceutical, and a comparison unit adapted to compare the determined property of the dispensed pharmaceutical with the predetermined identifying information. In addition, a method of verifying a prescription, wherein the prescription comprises a pharmaceutical compound, comprises associating the prescription with a unique identifier, storing the unique identifier, determining the identity of the pharmaceutical compound, and comparing the identity of the pharmaceutical compound with the unique identifier.

Abstract: An infrared absorption spectrometer features an optical microcavity, and a waveguide that evanescently couples light into the microcavity. The optical resonance frequency of the microcavity is tuned to coincide with an atomic or molecular resonance frequency of a selected atom or molecule. In this way, light coupled into the microcavity will experience absorption in the presence of an atomic or molecular subtance. The absorption causes a measurable change in the evanescent light coupling into the microcavity. The detection sensitivity of the spectrometer is significantly increased, compared to prior art spectrometers, because of the high Q value of the microcavity and the ensuing long optical path lengths of the resonant modes traveling within the microcavity.

Abstract: A mid-infrared (mid-IR) spectrometer attachment performs reflection spectroscopy measurements using commercially available infinity corrected light microscopes. The mid-IR spectrometer attachment introduces infrared radiation into the optical path of a visible light microscope. Radiation from the mid-IR spectrometer source is directed by a radiation director to a mid-IR objective lens affixed to the microscope nosepiece. The objective lens focuses the radiation on to a subject sample surface in order to acquire either internally or externally reflected infrared spectra by subsequently directing the sample encoded reflected infrared radiation to an infrared radiation detection system. The mid-IR spectrometer attachment is mechanically and optically compatible with a plurality of commercial infinity-corrected visible light microscopes.

Abstract: A disc serving as a spatial radiation modulator has dispersed radiation filters thereon. Each filter has a transmittance or reflectance modulation function of the form sin2(m&thgr;+p&pgr;/4), where m is a positive integer and p has one of the four values 0, 1, 2, 3. A radiation beam including selected wavelength components is diffracted into an elongated image dispersed according to wavelength. Different wavelength components are focused onto different filters on the modulator and are encoded by correspond filters. Since the modulation functions of the filters are orthogonal to one another, it is possible to extract the amplitude of each wavelength component after it has been encoded or modulated by corresponding filter from the total detected signal during one measurement.

Abstract: A method and a device are disclosed for determining the thickness and growth rate of an ice layer on structural component parts, particularly of aircraft, wherein the thickness and growth rate of an ice layer are determined and displayed in a simple, economical and dependable manner. To this end, a method is disclosed by which the radiation incident on a surface covered by an ice layer or disturbing layer is separated spectrally by a holographic grating connected with a line receiver into enough wavelength regions that a correction of the ice absorption is achieved by comparing the measured radiation with a stored reflection curve of an uncoated surface and by combining the comparison values and determining the peak area in the wavelength region of the ice absorption, and wherein from the thickness of the ice layer and disturbing layer and the ice thickness values obtained in the measurement intervals the growth rate of the ice layer is determined and displayed.

Abstract: An extremely convenient apparatus for evaluating the inner quality of vegetables and fruits which is small and inexpensive, can be introduced easily even by small-scaled enterprisers, in which an installation place can be changed easily, and safety and promptness of the replacing work of light sources are fully taking into consideration is provided.

Abstract: Described is a method which uses spectral data simultaneously collected in a continuous array of discrete wavelength points of the visible spectrum adjacent to the infrared and near infrared part of the light spectrum. The spectral data is collected using a number of detectors with different sensitivity ranges. Some detectors may be sensitive to visible and possibly, to part of the near infrared portion of radiation. Spectral data from die infrared spectrum is collected with the infrared detectors, and are in some embodiments insensitive to the visible links.

Abstract: In an infrared analysis instrument, a fiber optic probe, designed to be inserted into a particulate sample, is formed from distal ends of transmitting and receiving optic fibers. The distal ends of the transmitting fibers are located centrally in the probe and the distal ends of the receiving fibers are formed in a ring around the distal ends of the transmitting fibers. The distal ends of the receiving fibers are set back from the distal ends of the transmitting fibers. The receiving fibers carrying diffusely scattered light reflected from and transmitted through the particulate sample to a spectrophotometer housing containing fixed grating and an array of silicon photodetectors arranged to detect the spectrum dispersed by the grating in the range of 500 to 1100 nm.

Abstract: A method and apparatus of determining the analyte concentration of a test sample is described. A temperature gradient is introduced into the test sample and infrared radiation detectors measure radiation at selected analyte absorbance peak and reference wavelengths. The modulation of the temperature gradient is controlled by a surface temperature modulation. A transfer function is determined that relates the surface temperature modulation to the modulation of the measured infrared radiation. Reference and analytical signals are detected. In the presence of the selected analyte, phase and magnitude differences in the transfer function are detected. These phase and magnitude differences, having a relationship to analyte concentration, are measured, correlated and processed to determine analyte concentration in the sample.

Abstract: A device and method for determining analyte concentrations within a material sample are provided. A modulating temperature gradient is induced in the sample and resultant, emitted infrared radiation is measured at selected analyte absorbance peaks and reference wavelengths. The modulating temperature gradient is controlled by a surface temperature modulation. One embodiment provides a transfer function relating the surface temperature modulation to a modulation of the measured infrared radiation. Phase and magnitude differences in the transfer function are detected in the presence of the sought-after analyte. These phase and magnitude differences, having a relationship to analyte concentration, are measured, correlated and processed to determine analyte concentration in the material sample. Another embodiment provides a method for transforming thermal phase spectra to absorption spectra for consistent determination of analyte concentration within the sample.

Abstract: A method for accurately measuring the reflectance of translucent objects by illuminating small areas of the object is disclosed. The method involves determining the lateral diffusion error by use of a predetermined set of calibration standards. The lateral diffusion error is added to the uncorrected reflectance to produce the corrected reflectance value. The method has widespread potential applications in the paper, printing, textile, coating, and food industries.