Abstract: Integrated sensors are described using lasers on substrates. In one embodiment, a first sensor forms a laser beam and uses a quartz substrate to sense particle motion by interference of the particles with a diffraction beam caused by a laser beam. A second sensor uses gradings to produce an interference. In another embodiment, an integrated sensor includes a laser element, producing a diverging beam, and a single substrate which includes a first diffractive optical element placed to receive the diverging beam and produce a fringe based thereon, a scattering element which scatters said fringe beam based on particles being detected, and a second diffractive element receiving scattered light.

Abstract: A method of detecting cancer using a laser biocavity having a semiconductor laser including a microchannel through which cells in fluid traverse, comprising determining the laser wavelength of the laser biocavity with only fluid in the microchannel; determining the wavelength shift of the biocavity when each cell passes through the microchannel; and determining the percentage of cells in G2 phase from the wavelength shift of the cells; wherein an increased percentage of G2 phase cells is an indication of cancer.

Abstract: The invention relates to a portable device for carrying out examinations of turbid media using a three-dimensional cross-correlation technique and for suppressing the influence of multiple scattering, as well as to an adjustment method for adjusting the device. The device has a base plate (1) upon which an adjustable laser (2) is positioned in tilting devices or by means of mirrors for directing the laser beam perpendicularly onto the wall of a cuvette (6) filled with a medium to be examined. The device is provided with a translucent plate (7) which in some sections is completely mirror-coated and in other sections is partially mirror-coated and which serves as a beam splitter (4). The plate is firmly secured to the base plate (1) using a positioning fixture (8) whose support surface (16) for the translucent plate (7) is situated at a fixed angle with respect to the base plate (1).

Abstract: The system images the volume of a turbid medium and detects the contents. The medium can be water or air, or living tissue, or almost any other material which is at least partially light-transmissive. The system includes a light source for producing a series of discrete fan-shaped pulse beams that are substantially uniform in intensity or have been peaked at the edges of the fan to illuminate sections of the medium, a streak tube with a large, thin-slit-shaped photocathode for collecting the maximum amount of light from weak returns, a field-limiting slit disposed in front of the cathode for removing multiply scattered light, a large-aperture optical element for collecting and focusing the reflected portions of the pulse beam on the field-limiting slit and the cathode, and an array of detectors.

Abstract: The invention relates to a detector for scattered light, especially for detecting particles in a carrier medium. Said detector comprises a housing (1) and an inlet (3) and an outlet (5) in the housing (1). The carrier medium flows through the housing between said inlet and outlet and on a flow path (7). The inventive detector also comprises a light source (9) that directs light to a scattered light centre (11) which lies on the flow path (7). The inventive detector further comprises a receiver (13) for a portion of the light which is scattered onto particles in the scattered light centre (15) and a light trap (15) for light which is not scattered in the scattered light centre (11). The aim of the invention is to improve such a detector for scattered light in such a way that compact construction and high responsiveness are guaranteed. The light trap (15) can be embodied in two ways.

Abstract: The invention provides a flow cell system for high throughput solubility testing of compounds that is particularly useful for screening large compound collections, such as combinatorial chemical libraries or other such synthetic chemical libraries. The system includes a flow cell to channel a fluid sheath which itself channels a continuous or intermittent sample liquid stream containing a compound for testing. Where the concentration of compound in the sample exceeds the solubility limit, particles of the test compound precipitate. These particles scatter the light from an interrogating light beam directed at the sample liquid stream. Individual flashes of scattered light are detected as electronic pulse signals from the detector and their intensity analyzed according to intensity and number of events. System software analyzes the stored pulse signal data in real-time to determine whether there is a significant increase in scattering over the highly variable background scattering.

Abstract: The object of the present invention is to provide a disease type and/or condition determination method and apparatus that enables rapid and reliable determination by spectral analysis of the energy state of cells or drugs, and a drug screening method and apparatus that enables efficient screening of a target drug. In order to achieve this object, for example, the disease type and/or condition determination method according to the present invention determines disease type and condition by measuring the absorption spectrum in, for example, the infrared region for cells obtained from a specimen, and determining whether or not a coinciding absorption spectrum exists for those measurement results by using as indices at least two infrared absorption spectra.

Abstract: A diffractive optic sheer stress sensor operates by forming diverging fringes over a linear area of measurement. A diode laser focuses light onto a diffractive lens which focuses the light to respective slits. The slits form diverging fringes, and scattered light from the fringes is collected by a window and focused by another diffractive lens to a receiver.

Abstract: An in-line particulate detector comprises a housing having an inner flow portion. The housing Is disposed between adjacent portions of pipeline to permit a fuel flow from a fuel source through the inner flow portion to a fuel consumer. A light source is positioned within the housing for emitting a light beam within the inner flow portion. A first photodetector is positioned within the housing to detect the full strength of the light beam. A second photodetector is positioned within the housing to detect low, baseline levels of the light beam. Circuitry is coupled to first and second photodetectors to monitor the ratio of light intensities. When a fuel containing particulates is introduced, the light beam is scattered and the intensity measured by the second photodetector will increase and the intensity measured by the first photodetector will decrease.

Abstract: Pulsed light of predetermined wavelengths or modulated light of predetermined frequencies from a light source 5 is injected into a scattering medium 1 as a measured object and output light therefrom is detected by a photodetector 7. Further, measuring methods and apparatus are configured so as to process and compute internal information by a signal processing unit 8 and an computation processing unit 9, and the internal information of the scattering medium 1 is obtained by calculating the difference between absorption coefficients by use of the time integrated spectroscopy (TIS method) and the phase modulation spectroscopy (PMS method) based on the MBL law in accordance with a spectroscopy method (MVS method) making use of a mean pathlength and a variance, or physical quantities equivalent thereto. This enables the internal information of the scattering medium to be measured accurately and quickly.

Abstract: Methods and apparatus are disclosed for determining the volume, hemoglobin concentration, maturity and cell shape of mammalian red blood cells in a whole blood sample and simultaneously monitoring system standardization. Methods for distinguishing red blood cells from other cellular particles, prior to the red blood cell analysis are also disclosed. Red blood cells are passed through a beam of light in single file at a selected wavelength, obtaining an initial cytogram by means of the resultant magnitude of one light loss signal and one forward angle light scatter signal at a selected angular interval and a third side angle light scatter or two forward angle light scatter signals at a selected angular intervals and a third side-angle light scatter signal, projecting the cytogram, point by point, onto a pre-calibrated 3-dimensional surface containing grid lines of volume and hemoglobin concentration and determining accurate values of cell volume and hemoglobin concentration.

Abstract: The invention relates to a device and a method for moving a measuring sensor (2) into and out of a pressurized or flow-through conduit (1) or a pressurized or flow-through vessel. The device according to the invention comprises, in this case, a holding element (3) for holding the measuring sensor (2), a guiding element (4) for guiding the holding element (3) and a volume element (5). The holding element (3) can be moved in such a way that the measuring sensor (2) held by the holding element comes to rest in a position completely in the volume element (5). In this position, the measuring sensor (2) can be removed from the holding element (3). With the aid of the device according to the invention and the method according to the invention, it is possible, in particular, to measure the cleanliness of a conduit system blown out with a fluid, without the blow-out operation being interrupted.

Abstract: The invention relates to a portable device for carrying out examinations of turbid media using a three-dimensional cross-correlation technique and for suppressing the influence of multiple scattering, as well as to an adjustment method for adjusting the device. The device has a base plate (1) upon which an adjustable laser (2) is positioned in tilting devices or by means of mirrors for directing the laser beam perpendicularly onto the wall of a cuvette (6) filled with a medium to be examined. The device is provided with a translucent plate (7) which in some sections is completely mirror-coated and in other sections is partially mirror-coated and which serves as a beam splitter (4). The plate is firmly secured to the base plate (1) using a positioning fixture (8) whose support surface (16) for the translucent plate (7) is situated at a fixed angle with respect to the base plate (1).

Abstract: A method and apparatus for determining the concentration of a constituent in a fluid by directing a beam of light into the fluid and sensing the intensity of components of the light emerging from the fluid at various wavelengths. The light emerging from the fluid can be light that has been attenuated by absorption or induced by fluorescent radiation. The effect of scattering on the light is minimized by normalizing the component intensities, which are then applied to an algorithm incorporating weighting factors that weighs the influence that the intensity at each wavelength has on the determination of the concentration of the constituent for which the algorithm was developed. The algorithm is developed by a regression analysis based upon a plurality of known mixtures containing various concentrations of the constituent of interest.

Abstract: A high-efficiency, high-sensitivity absorbance detection system in a lab-on-a-chip is provided. The absorbance detection system includes detection cells having an optical pathlength ten times and/or much longer than the width of a separation channel to improve detection sensitivity, lens structures for collimating light in the detection cells, and slit structures for preventing scattered light from entering detectors. The detection cells, the lens structures, and the slit structures of the absorbance detection system are fabricated and integrated in a lab-on-a-chip. The absorbance detection system exhibits excellent absorption efficiency, detection limit, and linearity, compared to existing absorbance detection systems, and can be applied for the detection of a variety of samples. The absorbance detection system does not need labeling of the samples which saves time and costs. The absorbance detection system can be used effectively in detecting trace compounds with a high sensitivity.

Abstract: The optical density of an oil sample at a plurality of wavelengths over a plurality of different (typically decreasing) pressures is monitored and used to find the size of agglomerated asphaltene particles which are precipitating from the oil sample. The optical density information used in finding the particle size is preferably optical density information relating to the scattering of light due to the asphaltene particles only. Thus, baseline optical density information of the oil sample at a high pressure is subtracted from optical density information obtained at test pressures at each wavelength of interest. Asphaltene particles of a radius of one micron and smaller were found to be powdery, while asphaltene particles of a radius of three microns and larger were found to include paving resins. The precipitation of asphaltenes is reversible by increasing the pressure under certain circumstances.

Abstract: An automated particle sorter having a fluid flow path, which places single biological particles in an optical cuvette. An exciting light irradiation system having a light source emits a source of light through the cuvette. The light excites a fluorescent substance present on the particle, and the emitted light is detected by a light detection apparatus containing at least two detection elements for measuring the fluorescence emitted from the fluorescent substance. A light separation element separates the fluorescence from the exciting light. A data processor compares the signal received from the fluorescent light; and from the background autofluorescent signal, and according to pre-set parameters, controls the position of a collection conduit between two set points. The first being a collection set point for the collection of objects having a first phenotype and the second being a set point for the collection of objects having a second phenotype.

Abstract: The invention relates to a method for carrying out mixing in a thin liquid layer, which is arranged between essentially parallel walls at a capillary distance from each other. The mixing is carried out by subjecting the walls to a motion essentially in the plane of the liquid layer, balancing the motion against the capillary force exerted by the walls on the liquid, and selecting the interface between the liquid layer and the surrounding medium so that it functions as an elastic membrane. The invention also concerns a cuvette which is designed for mixing according to the method.

Abstract: This invention relates to electrochromic devices that are protected against UV light by nanoparticles.

Abstract: A dynamic light scattering apparatus comprises at least two lasers (11) of different wavelengths which illuminate the same volume (SV) of a fluid containing scattering or fluorescent centres. The scattered or fluoresced radiation is detected at each discrete wavelength and properties, such as the concentration of different particle sizes, of the volume (SV) are derived. The detection at multiple wavelengths allows the effects of multiple scattering to be overcome. Multiple volumes (SV) may be illuminated and detected simultaneously so as to measure the spatial variation of particle size concentration. The rotational diffusion constants of the particles may be measured from the depolarized component of scattered light.

Abstract: An integrating nephelometer is modified to measure 180° backscattering from an aerosol. A laser is mounted outside a housing of the nephelometer and produces a coherent light beam that is directed into a sample volume of the nephelometer, substantially along an optical sensing axis (<4° off the optical axis). Light from the laser beam that is reflected by an aerosol travels back along the optical sensing axis toward a photomultiplier tube (PMT) light detector, which thus produces a signal indicative of the backscattering from the aerosol. A portion of the laser beam is conveyed into the housing of the nephelometer through an optical fiber for use as a reference beam. A motor-driven chopper disk disposed across the optical axis is divided into an open sector, a calibration sector (with a very low transmission), and a flat black light absorbing sector.

Abstract: The invention relates in particular, to the area of devices or systems whose optical operation is modified by changing the optical properties of the medium of which they are formed and that are intended, in particular, for limiting the luminous intensity transmitted by the system. Specifically, the invention relates to a device for selectively limiting the intensity of a radiation, including a liquid or solid medium containing nanotubes, for example, nanotubes made of carbon or boron, tungsten, silicon, or composite nanostructures, such as BN, BC3, BC2N, CN(C3N4), or MoS2.

Abstract: Particle detecting apparatus for detecting other particulate matter comprises a measuring section and an input/output section removably attached together. A measuring chamber receives gaseous fluid by diffusion from a receiving chamber connected via an inlet to an area being monitored. The measuring chamber comprises a cylindrical body housing pairs of light emitting diodes positioned diametrically opposite, and directing light towards, each other through a sampling volume viewed by a photo-diode through a viewing aperture. The photo-diode detects light scattered by particles in the sampling volume. A glass tube protects the LEDs from contamination and can easily be cleaned or removed. Each LED can temporarily be de-energised in turn so as to act as a light detector, its output in response to light received from the opposite LED being thus a measure of any contamination. The measuring and input/output sections can easily be separated for servicing or replacement.

Abstract: A method for measuring the end point and for monitoring the real time kinetics of a bioaffinity reaction in biological fluids and suspensions, employing microparticles as bioaffinity binding solid phase, biospecific reagent labelled with a fluorescent label and a fluorescence detection system which is based on two-photon fluorescence excitation, contacting the analyte, the labelled reagent and the solid phase simultaneously, focusing a two-photon exciting laser beam into the reaction suspension and measuring the fluorescence signal emitted by the microparticles from one particle at a time when they randomly float through the focal volume of the laser beam. In this method the signal is monitored kinetically to obtain information about the analyte concentration before the reaction approaches the highest point of the response. Since the growth rate of the signal intensity is directly proportional to the analyte concentration, the analyte concentration can be predicted in the initial phase of the reaction.

Abstract: A homogeneous biospecific assay method for an analyte in solution or in a biological suspension, in which a biospecific reagent competitively binding an analyte and a ligand labeled with a fluorescent molecule, is reacted with and bound to a solid phase, and in which the free labeled ligand is extracted is excited with two-photon excitation by focusing a laser beam suitable for two-photon excitation into the sample volume; and the concentration of the analyte is calculated based on the photon emission contributed by the free labeled ligand.

Abstract: The present invention includes a method and an apparatus for the quantitative determination of particles in fluid. The apparatus of the invention includes an emitters set of one or more light emitters, in combination with a detector set of one or more light detectors sensitive to the output of the emitters. During analysis of the sample, data from a plurality of signal paths between the emitter and detector sets are gathered. This information is subsequently evaluated by comparison with known data for different fluid particle contents. Some differentiation between different particles in a fluid sample are possible in many embodiments. Typical uses include analysis of milk and dairy fluids, blood samples, lubricants, suspensions of pigments, etc.

Abstract: A film suitable for use as the light-modulating unit of a light valve, is disclosed. The film comprises a cross-linked polymer matrix having droplets of a liquid light valve suspension distributed in the cross-linked polymer matrix. The polymer matrix, prior to cross-linking, comprises a polymer having a Brookfield viscosity of at least 2000 CPs.

Abstract: A method and apparatus are for characterizing colloids by successive measurements of light attenuation or emission of a colloidal mixture at two or more temperatures and at one or more wavelengths. The difference or ratio of the measurements at two or more temperatures provides a measure of the colloidal stability with respect to temperature. The amount of certain organic colloids that are unstable to temperature variation may be determined from the magnitude of the measurement change. In appropriate mixtures, this method provides a means to distinguish components of colloidal substances based. This method may be specifically applied to determining the stability and concentration of colloidal pitch or wood resin in a pulp or paper process water. In this context it may be used to distinguishing colloidal pitch or wood resin from talc, clay, carbon black, or other fillers.

Abstract: A method for determining light scattering efficiency and a method to determine undertone of pigments or mixtures containing white pigments are described. The methods are based on measuring total transmittance of pigment slurries at a wavelength of at least 600 nm. Transmittance measurements can be used to calculate light scattering efficiencies and undertone which correlate with performance in end-use applications.

Abstract: An optical apparatus for and method of improving collection efficiency and signal strength of optical instruments used in capillary electrophoresis, such as laser-induced fluorescence detectors are provided. The apparatus and method provides a concave reflector positioned at one side of the capillary flow cell as a first high numerical aperture (N.A.) collector, a lens collector positioned at an opposite side of the flow cell as a second high N.A. collector, and an optical fiber positioned at close proximity of the flow cell for delivery of an excitation light to cause a sample contained in the flow cell to emit emission lights. The reflector has a concave surface for reflecting the emission lights, and the collector has a proximal convex surface for collecting the emission lights, and a distal convex surface for collimating the emission lights. This arrangement achieves a larger solid collection angle from both sides of the flow cell and therefore an increased collection efficiency.

Abstract: On-line measurements of an amount of dissolved solids in a liquid sample are determined by using both conductivity and UV measurements. More particularly, an amount of dissolved solids in a pulp and paper mill process water or effluent is determined by irradiating at least a portion of a liquid sample with ultraviolet light and subsequently measuring an absorption of the light by the liquid sample. Furthermore the conductivity of the liquid sample is measured and subsequently a computation is from a first relationship between the measured absorption of the first wavelength by the liquid sample and the measured conductivity of the liquid sample using a suitably programmed processor.

Abstract: The invention provides an improved process for determining the characteristics of dispersed particles. The process involves directing waves (acoustic or light) into a dispersion, and measuring the attenuation of the waves for particular frequencies to provide an attenuation spectrum. The measured attenuation spectrum is then compared to a set of theory-based calculated attenuation spectra to determine the particle size distribution corresponding to the measured attenuation spectrum. Unlike previous processes, the particle size distribution is capable of being accurately determined by a single inversion algorithm, thus eliminating burdensome steps of previous methods.

Abstract: A submersible light scattering probe for the absolute characterization of polymer and colloid solutions includes a ring member made of a preferably dark, opaque material, having embedded therein a plurality of optical fibers which can be connected to optical detectors remote from the probe. The ends of the optical fibers are preferably in direct contact with the fluid being tested. Instead of submersing the probe in a fluid, fluid can be caused to flow through the probe, placed in the probe, or placed in a transparent vessel placed in the probe. Individual large scattering particles can also be detected, counted, and characterized at the same time absolutes characterization of the polymer or colloid solution is performed.

Abstract: An apparatus and a method for transfusing liquid specimen for an optical characteristic measurement, which is excellent in operability and handling, and capable of introducing a liquid specimen into a sample cell without detaching the cell from an optical characteristic measurement apparatus and without bubbling, as well as a polarimeter are disclosed. According to the present invention, the specimen can be introduced into the sample cell without detaching the sample cell from the equipment, in a way of connecting the bottom of the sample cell with a reservoir for temporarily accommodating the liquid specimen through a tubular path, then varying a difference in the levels of the sample cell and the reservoir, or a way of using a syringe arranged in the tubular path. At expelling the specimen from the sample cell, the specimen is transfused into the reservoir in a similar manner.

Abstract: A method for determining light scattering efficiency and a method to determine undertone of pigments are described. The methods are based on measuring total transmittance of pigment slurries at a wavelength of at least 600 nm. Transmittance measurements can be used to calculate light scattering efficiencies and undertone which correlate with performance in end-use applications.

Abstract: A disposable first tube (68) extends axially through, and is detachably connected to, an annular main body (10'). An input piezo electric element (38) is attached to a first end of the tubular main body (10'). A second, sensor piezo electric element (40) is attached to the opposite end of the main body (10'). A nozzle (20') having a nozzle passageway (110) and a discharge opening (112) is detachably secured to an outlet end of the first tube (68). A second tube (102) within the first tube (68) delivers a core liquid to the nozzle passageway (110). A sheath liquid is delivered through a space in the first tube (68) surrounding the second tube (102). The nozzle passageway (110) forms the core and sheath liquids into a small diameter jet stream. Electrical energy is delivered to the input piezo electric element (38), to vibrate the nozzle (20') and break the jet stream into droplets.

Abstract: A system for detecting objects in a turbid media utilizes an optical parametric amplifier as an amplifying gate for received light from the media. An optical gating pulse from a second parametric amplifier permits the system to respond to and amplify only ballistic photons from the object in the media.

Abstract: Apparatus for sampling a laser beam used in an analytical instrument, e.g., a clinical hematology or flow cytometer instrument, for measuring absorption by particles suspended in a stream moving through a flow cell. The laser beam is typically passed through a mask, e.g., a beam shaping aperture, to shape the beam. The shaped beam is then passed through a beam splitter, located downstream of the beam shaping aperture, so that one part of the shaped beam strikes the flow cell (e.g., is focused onto the moving stream of particles), and a second part is diverted to obtain a reference measurement of the beam about to strike the flow cell. An absorption measurement is obtained of the light passing through the flow cell, and a difference circuit is used to obtain a difference signal relating the differences between the measured absorption and the unabsorbed reference sample of the initial beam intensity.

Abstract: A disposable first tube (68) extends axially through, and is detachably connected to, an annular main body (10'). An input piezo electric element (38) is attached to a first end of the tubular main body (10'). A second, sensor piezo electric element (40) is attached to the opposite end of the main body (10'). A nozzle (20') having a nozzle passageway (110) and a discharge opening (112) is detachably secured to an outlet end of the first tube (68). A second tube (102) within the first tube (68) delivers a core liquid to the nozzle passageway (110). A sheath liquid is delivered through a space in the first tube (68) surrounding the second tube (102). The nozzle passageway (110) forms the core and sheath liquids into a small diameter jet stream. Electrical energy is delivered to the input piezo electric element (38), to vibrate the nozzle (20') and break the jet stream into droplets.

Abstract: A method and apparatus for determining the types and amounts of impurities contained in a fluid medium wherein light is projected into a fluid medium and light which is not absorbed by impurities contained in the fluid medium is transmitted to a spectrometer or photomultiplier. The relationship between the light injected into the fluid medium and the light transmitted out of the fluid medium is analyzed to determine the amounts and types of impurities contained in the fluid medium based on the percentage of light of certain wavelengths transmitted out of the fluid. The apparatus comprises a probe which preferably is slip-stream fit to a pipeline through which the fluid medium flows. The probe is coupled to a light source, such as a tunable laser, by a first fiber and to a spectrometer or photomultiplier by a second fiber. Light is transmitted along the first fiber to the probe from the light source and from the probe to a spectrometer or photomultiplier along the second fiber.

Abstract: A method is provided to test turbidity sensors using a solid block that is particularly formulated to have a predetermined turbidity value. The solid block, which is partially transparent, is made by mixing calcium carbonate with a clear acrylic. A plurality of sample sensors are selected to be used as an intermediate standard to correlate the results achieved when the block is tested to results that would be achieved if liquid turbidity samples are tested. The six sample sensors are used to measure the turbidity of a plurality of liquid samples. The six sample sensors are then used to test the solid block in order to make sure that the turbidity represented by the solid block is within an acceptable range that is normally dictated by either a national standard or a particular customer requirement. Each of the plurality of sample sensors is used to test the solid block a plurality of times to form an average ratio value that can be used as a first representative magnitude for each of the sample sensors.

Abstract: Method of assay of enzymatic activity, comprising projecting excitation light to a sample containing an enzyme, a substrate which forms a product by action of the enzyme, and a reference substance which is insensitive to the action of the enzyme but emits fluorescence; obtaining a first measured value of fluorescence intensity of the sample at a first wavelength region which includes fluorescence emitted by the substrate or the product at least, obtaining a second measured value of fluorescence intensity at a second wavelength region which is different from the first wavelength region for the first measured value and includes fluorescence emitted by the reference substance; and assaying the enzymatic activity from the ratio of the first measured value to the second measured value and apparatus for performing the method. The method assures high accuracy and high sensitivity of measurement in enzyme labeled immunoassay and enzyme labeled DNA hybridization.

Abstract: A particle image in a sample is formed at an imaging position by an objective lens of a microscope, projected on the image picking up plane of a TV camera via a projection lens and is subjected to photo-electric conversion. Image signals from the TV camera are supplied to an image memory via an A/D converter as well as to an image processing control unit. Image signals outputted from the image memory are supplied to a characteristic picking out unit and there a plurality of characteristics of the particle concerned are picked out. The picked-out characteristics are supplied to the classification unit and there classification of the sediment components is perfumed via a neural network with a learning capability. Accordingly, the classification unit performs provisionally an automatic classification of the objective sediment components by making use of the inputted characteristic parameters.

Abstract: The granulometer uses a measuring laser beam (9) to illuminate particulate and, through the measure of the distribution of the light diffused by the examined particulate and gathered by a collecting lens (11), measures the concentration of particulate in the fluid in low concentration standards, the laser beam (9) being a converging one focused on a laser opaque shell (12) that partly covers the same lens.

Abstract: An assay for photometrically detecting and/or quantitating the presence of an analyte in a sample in which the signal generated by a label associated with the analyte is photometrically detected in the presence of a suspended solid support.

Abstract: A apparatus for sensing flow and/or other characteristics of a fluid, including an emitter adapted to project a light beam, a detector adapted to transmit a signal in response to receiving the light beam and a rotatable member for transmitting the beam of light from the emitter to the detector through a quantity of the fluid. Optic fibers/light pipes may be used to transmit light to the emitter from a light source, through the rotatable member and to a processor remote from the detector. The rotatable member may also include reflective and nonreflective zones for transmitting light passing through the fluid to the detector. A plurality of light pipes, blades, emitters and detectors may be used on the rotating member depending on a particular application of the present invention.

Abstract: In a method for measuring a specified component in a specimen by reacting the specimen with a first reagent formed by binding a substance active to the specified component, with carrier particles and a second reagent formed by labelling a substance active to the specified component with a first label, and measuring the substances in the complexes obtained in the reaction, there is disclosed a method featured by labelling the carrier particles with a second label different from the first label, and detecting the second label and then the first label utilizing the detection of the second label as a trigger.This method enables a highly precise measurement without the influence of noise components in the detection of specified trace components in the specimen, utilizing an antigen-antibody reaction or a nucleic acid hybridization.

Abstract: A multi-purpose on-line or field-portable system and method for monitoring the presence and concentration of selected antigen-antibody reactions singly or in combination that result from the presence of specific microorganisms or free antigens present or suspended in aqueous solutions, during a given time period. The detection system comprises a detection column and two sensors mounted around the J-shaped detection column. Each sensor consists of an electromagnetic radiation source and an appropriate detector for the electromagnetic radiation. The reacted analyte tends to accumulate at the sensor located in the curve of the J-shaped detection column. The lower sensor continually nulls against the upper sensor to subtract any optical effects due to non-reactants in the aqueous process or environmental stream. The response from the detector sensors drive an electric circuit, which provides an output signal.

Abstract: A coating system for detecting the presence of contaminants carried by a fluid that is applied as a coating on a workpiece. A tube guides the fluid along a flow path to the workpiece. A light source illuminates the fluid along at least a portion of the flow path, and this light is scattered by any contaminants present in the fluid. Light scattered by the contaminant particles is more intense than light scattered by the other fluid particles, and this brighter scattered light is detected by a light detector positioned adjacent to the fluid flow path. If one or more contaminant particles is detected in the fluid, a warning signal can be given and/or the flow of fluid can be stopped. This coating system is particularly well suited for use in a spin-on coating process that applies a liquid, such as a photoresist material or a dielectric material, to a semiconductor wafer or other workpiece that is secured to a rotating turntable.

Abstract: The free resin particles which present problems in papermaking are determined according to number and size in order to bind them to the wood fibers by adding assistants and hence render them harmless. For this purpose, a paper stock suspension is prepared and the resin particles are separated from said suspension and then marked with a fluorescent dye and isolated. The light signals emitted by the individual resin particles after excitation are detected for determination of number and size.