Abstract: The present invention relates to a method and a device for determining a concentration of a biological active substance in a sample by the means of an enzyme-linked immunosorbent assay (ELISA). The device comprises a solid support within a tubing for binding an immunosorbent and an inlet for fluids, a detector for detecting radiation due to an activity in the tubing, wherein the tubing is arranged inside a microchip extending substantially in one plane, for conducting the fluids along the plane of the microchip. The tubing forms a reaction cell having a large detection area. The reaction cell of the microchip is arranged perpendicular to the detector. The method comprises the steps of introducing the fluids into the tubing, conducting the fluids through the tubing forming a reaction cell, in which reaction cell the radiation emitting activity takes place, and detecting the light emitted from the reaction cell substantially perpendicular to the plane.

Abstract: A fault detection and classification method is disclosed that uses raw back-focal-plane image data of radiation from a substrate surface, detected by a scatterometer detector, to determine a variation in the raw data and correlate the variation in the raw data with a possible fault in a lithographic apparatus or a process that patterned the substrate surface. The correlation is carried out by comparing the variation in the raw data with known metrology data. Once a fault has been determined, a user may be notified of the fault.

Abstract: The present invention relates to a method, system and apparatus for continuously monitoring variations in the size of particles present in a fluid on a real time basis. The method comprises of passing one or more optical signal through the fluid such as engine oil. The variation (attenuation or enhancement) in the intensity of the optical signal is continuously measured with respect to time. In an embodiment, the method, system and apparatus of the present invention enable monitoring of the amount, size and onset of particle agglomeration using single or multiple wavelengths as interrogating optical signal(s). An exemplary embodiment is provided for monitoring of the amount, size and onset of soot particle agglomeration in engine oil using single or multiple wavelengths as interrogating optical signal(s).

Abstract: An optical detection system for flow cytometry that uses light sources positioned laterally at different distances from the central axis of the flow stream for providing light through different parts of the flow stream. By using two or more light sources, the particle position can be detected, and the alignment and width of the core stream can be monitored and controlled.

Abstract: An apparatus for detecting particles in an airflow is disclosed. The apparatus can include at least one light source for illuminating a one or more portions of the airflow, at least one photo-detector positioned to detect light scattered from one or more illuminated volumes of the airflow. The at least one light source and at least one photo detector are arranged such that a signal indicative of light scattered from a plurality of illuminated volumes can be derived from the output of the at least one photo detector. The apparatus also includes a signal processing apparatus configured to process said signals indicative of light scattered from a plurality of illuminated volumes to determine whether particles have been detected in the airflow.

Abstract: Values for one or more particle properties, such as an aerosol asymmetry parameter g, can be measured directly using a detector that measures scattered light. The detector can comprise two or more diffusers coupled to optical sensors responsive to scattered light that is incident on the surfaces of the diffusers. One or more weighing functions can be obtained based on diffuser geometry. In an example, the diffusers correspond to quadrants of a circular toroid.

Abstract: A method and apparatus for analyzing particles in a fluid, such as proteinaceous particles in a pharmaceutical formulation intended for parenteral delivery, are disclosed. The method comprises arranging a fluid to form a wide and shallow stream, acquiring a sequence of magnified still images of the stream, and processing said images, so as to highlight images of particles in the flowing fluid. The apparatus includes a light source, a flow cell, a lens with increased depth of view, a detector array, and a processor for acquiring and processing the images of particles in the fluid stream.

Abstract: Disclosed are a turbidity sensor, which correctly senses a turbidity of water although the surface of the turbidity sensor is covered with foreign substances, such as scale, and an electric home appliance having the turbidity sensor. The turbidity sensor includes a light emitting part emitting light, a first light receiving part receiving light emitted from the light emitting part and travelling straight, a second light receiving part receiving light emitted from the light emitting part and scattered, and a control unit determining a turbidity of water according to a ratio of the amounts of the light received by the plurality of light receiving parts. The first light receiving part is installed in a direction of directly receiving the light emitted from the light emitting part, and the second light receiving part is installed in another direction of not directly receiving the light emitted from the light emitting part.

Abstract: A polarization lidar system capable of remotely identifying characteristics of atmospheric aerosol particles by transmitting a polarized beam of light and analyzing polarization characteristics of received backscatter is disclosed. The transmitter features high pulse energy to remotely identify aerosol particles with substantially one pulse. The transmitter employs a thin film plate polarizer and a Raman wavelength shifter to achieve eye-safe, single-plane linearly polarized energy. The transmit beam and receiver field of view are coaxial. The receiver employs a telescope, a collimating lens, and a beam splitter. The beam splitter splits the received backscatter into a single-plane polarized beam whose polarization plane is parallel to the plane of transmission and a single-plane polarized beam whose polarization plane is perpendicular to the plane of transmission. Each split beam is directed through separate focusing lenses onto separate detectors.

Abstract: System and method for fluorescent light excitation and detection from samples to enhance the numerical aperture and/or reduce the cross-talk of the fluorescent light.

Abstract: Systems and methods for sensing air includes at least one, and in some embodiments three, transceivers for projecting the laser energy as laser radiation to the air. The transceivers are scanned or aligned along several different axes. Each transceiver receives laser energy as it is backscattered from the air. A computer processes signals from the transceivers to distinguish molecular scattered laser radiation from aerosol scattered laser radiation and determines air temperatures, wind speeds, and wind directions based on the scattered laser radiation. Applications of the system to wind power site evaluation, wind turbine control, traffic safety, general meteorological monitoring and airport safety are presented.

Abstract: System and method for fluorescent light excitation and detection from samples to enhance the numerical aperture and/or reduce the cross-talk of the fluorescent light.

Abstract: The invention relates to a device (10) and a method for automatically eliciting a thermal avoidance response in nematodes, particularly in order to test pharmaceutical substances. The device (10) has a bearing surface (12) on which sample containers (14) of nematodes (16) are disposed, a laser (18), a selective laser-beam interrupter (27) to regulate the length of the laser pulse, aft and a scanner (22) for projecting and focussing the laser beam and for controlling a deflection. A light source (28) illuminates the sample container (14) with light, which brings about a contrast in the nematodes in the container. An additional light source (29) can also illuminate the sample container (14) with light in order to excite fluorescence-labeled areas of the nematodes, causing them to fluoresce. A real-time image processing device connected to the camera (30) determines the respective positions of all areas relevant for laser irradiation of the nematodes and makes this information available to a controller (32).

Abstract: A blood sample containing leukocytes flows through a flow cell. A light source emits a light beam in a first direction. The light beam incident into the flow cell is scattered by the blood sample as scattered light. A first detector detects an intensity of forward small scattered light out of the scattered light. The first detector is arranged so as to have a maximum angle of a detection angle range for the forward small scattered light stemmed from the first direction at a position inside (outside) of the flow cell, which is 3.1 (4) degrees or less. A second detector detects an intensity of forward large scattered light out of the scattered light. The second detector is arranged so as to have a detection angle range for the forward large scattered light stemmed from the first direction at a position inside (outside) of the flow cell, which falls in a range from 8 to 12 (10 to 16) degrees.

Abstract: Methods for enhancing the dynamic range for specific detection of one or more analytes in assays using scattered-light detectable particle labels. The methods involve utilizing variations in detection technique and/or signal processing to extend the dynamic range to either or both of lower and higher concentrations.

Abstract: A system for detecting when a core stream in a channel of a flow device is adequate for sufficient data accession. The system may determine the time period from the beginning of a sample run in a channel of a flow device to when the core stream is adequate. Data of detected FALS versus SALS light scattered by particles of the core stream may be plotted in data frames during a series of time intervals. The quality of the grouping and count rate of the data may indicate which frame and corresponding time interval reveal an adequate core stream.

Abstract: Differential signals and sum signals are extracted from a detection signal of passing light detected when a light beam emitted to an analysis optical disc passes through a particle on the disc. Presence of the particle is decided based on the differential signals, effectiveness of counting particles is decided based on the sum signals, and the decision results are stored. The stored decision results are scanned by using a scanning window corresponding to a minimum size of measured objects, particles having the minimum size are detected, and the number of detected particles is stored. Subsequently, the stored decision results are scanned using a scanning window corresponding to a size larger by one scan than the maximum size of the measured objects, particles having a size larger by one scan than the maximum size are detected, and the number of detected particles is stored.

Abstract: A photon correlator comprises a plurality of sampling gates 11a-11e which are open during different periods of time; a plurality of memories 12a-12e each provided corresponding to each of the plurality of sampling gates 11a-11e for storing data corresponding to the number of photons; and a data processing control section for reading out the data stored in the memories 12a-12e, and performing a correlation calculation by means of software. The mechanism of the hardware comprising the sampling gates 11a-11e and memories 12a-12e enables high-speed writing of data in the memories and real-time read out of the data. In addition, the software performs correlation calculations in parallel with the above processing. Accordingly, the particle sizes and diffusion coefficient of particles in a fluid can be obtained at high speed under various conditions.

Abstract: A MOS ring oscillator includes a number of serially connected inverter stages with each stage comprising a MOS transistor pair. At least one of the transistors also comprises a scatterometry grate array, which is used during manufacturing of the ring oscillator to obtain scatterometry measurements that allow polysilicon lines of the MOS ring oscillator to have widths of less than 60 nm. A method includes forming at least one grate array above a substrate, illuminating the grate array, measuring light reflected off of the grate array to generate an optical characteristic trace for the grate array, and comparing the generated optical characteristic trace to a target optical characteristic trace that corresponds to a grate array having a desired profile.

Abstract: A particle size distribution analysis apparatus comprising a sample measurement zone adapted to define a sample of particles, a light emitting means adapted to provide a source of light incident upon the sample measurement zone, and at least a first detection means adapted to measure light levels in the apparatus at particular scattering angles and output a signal to a computation means enabling the particle size distribution of particles contained within the sample to be determined, wherein the computation means is adapted, in use, to calculate a particle size distribution taking into account reflections by the measurement zone of light scattered off the particles.

Abstract: A method for determining absolute number densities of particles in a solution is disclosed based on a light scattering method. A light scattering photometer is calibrated to produce the Rayleigh ratio at each angle measured with respect to light scattered per unit incident intensity, per unit volume illuminated within the field of view of each detector per steradian subtended by said detector. In order that the numbers calculated be accurate, the illuminated particles should be effectively monodisperse. From the excess Rayleigh ratios measured at a plurality of angles with respect to the incident light beam illuminating said sample particles, an effective size is calculated which, in turn, is used to calculate the differential scattered intensity at each angle. The number of particles per unit volume element is then determined from the measured excess Rayleigh ratio divided by the corresponding differential scattered intensity.

Abstract: A vacuum chamber includes chamber walls separating a chamber interior and a chamber exterior, with one or more access ports defined in the chamber walls. A viewing tube extends from the chamber exterior into the chamber interior and terminates in a window. A positioner for imaging devices is then provided within the viewing tube, and is thus situated at least partially within the chamber interior with its imaging device(s) oriented towards the window of the viewing tube to allow imaging of areas within the vacuum chamber. The positioner preferably allows translation and/or rotation of an imaging device within the viewing tube within two perpendicular planes oriented along the axis of the viewing tube, thereby allowing the imaging device to view an area of interest from more angles oriented about the area of interest than would otherwise be possible if the imaging device was situated outside the vacuum chamber.

Abstract: The process is used for the screening of molecules from molecule libraries with regard to their individual binding behavior towards at least one given ligand. For this purpose the ligands labelled with a fluorescent dye are mixed with the molecule library which is in the form of a suspension. The mixture is plated out on a two-dimensional substrate (2) after the excess, unbound ligands have been washed out. Then the local fluorescence intensities on the substrate are electro-optically identified in a fluorescence microscope (5) and electronically discriminated in accordance with given selection criteria. The objects selected and localised in this way are then sequentially positioned exactly by a displacement, the coordinates of which are controlled by the image calculator, between the substrate (2) and a separation actuator (20, 21) and are spatially separated from the substrate (2) by the separation actuator (20, 21).

Abstract: Conventionally, reaction measurement for a reaction using semiconductor nanoparticles has been conducted by measuring absorbance and fluorescence intensity in a solution, and thus only a relative evaluation has been available, and its operation is complicated. The present invention provides an industrial evaluation method that is simply performed by conducting the measurement after a semiconductor nanoparticle solution is dried. Further, the measurement in a dry condition allows semiconductor nanoparticles to be applied to biopolymer microarrays or the like.

Abstract: Methods and apparatus using the principles of time-resolved spectroscopy are disclosed. The present invention employs incident light pulses of sufficiently short duration to permit the rate of the rise and decay of such pulses to be measured. Consequently, the rate of decay, u, permits a determination of the concentration of an absorptive pigment, such as hemoglobin. The present invention also allows the precise path length the photons travel to be determined. Using this path length information and by measuring changes in optical density using known continuous light (CW) spectrophotometry systems, the methods and apparatus disclosed allow changes in the concentration of an absorptive pigment to be correctly be measured. From these data, the oxygenation state of a tissue region, such as the brain, can be accurately determined in real time.

Abstract: A method is described to determine the 2nd virial coefficient of an ensemble of molecules dissolved in a selected solvent. Two distinct classes are described: monodisperse and polydisperse molecules. If the molecules are monodisperse, they must be prepared for a chromatographic separation and suitable columns selected. Following standard chromatographic separation procedures such as exemplified by the method of size exclusion chromatography, the sample passes through the separation columns, a multiangle light scattering detector, and a concentration detector. The effect of the columns is to produce a concentration profile of said sample that appears as a peak as it passes through the light scattering and concentration detectors. For each elution interval, &ngr;i, a corresponding concentration value ci and set of excess Rayleigh ratios Ri(&thgr;j) is measured for each scattering angle &thgr;j.

Abstract: A smoke detector is disclosed in which smoke particles are detected by the collection and detection of blue light and infra-red radiation which are emitted into a predetermined path through a scattering volume where the particles may be present. The scattered blue light and the scattered infra-red radiation are collected by an ellipsoidal mirror and focussed onto a suitable detector and then compared to produce an output which indicates either that the detected particles are smoke particles or that they are not smoke particles. The radiation collected by the mirror has been scattered through angles substantially less than 45° and preferably between about 10° and 35°.

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: In detecting a boundary line between areas different in light reflectance, it has so far been impossible to specify the boundary line at a distance shorter than the arrangement pitch of photodetectors (pixels) arranged in the camera. In the present invention, luminance variations near the boundary line between areas different in light reflectance are derivated. Further, in unit blocks G corresponding to pixels and arranged in a direction (Y direction) in which the boundary line extends, derivated values of luminance for each row of unit blocks are added and then a variation curve of the added values of derivated luminance values in unit block rows is drawn to specify a peak position thereof and also specify the position of the boundary line X0. Thus, it is possible to specify the position of the boundary line with a high accuracy at a distance shorter than the unit block pitch.

Abstract: The present invention relates to a method for instrument determination of measured variable L(t) which changes with time, the intention being to determine the maximum rate value of L(t) in a region with a linear reaction profile, and the time as well as the duration of the reaction time window being variable with the linear region and depending on the nature of the reaction and the reaction conditions. Specifically, the present invention relates to the determination of protein concentrations with the aid of light scatter, which is produced by specific antibodies, in homogeneous solutions. In particular, the invention relates to reactions which take place slowly and have a largely linear profile over a relatively long time, the rate of formation of antigen-antibody complexes in the linear section of the reaction (VMaxLin) being determined as the measured variable.

Abstract: Optical telecommunications system, comprising: a transmitting station capable of emitting an optical signal having a power of between 18 and 30 dBm; an optical fibre transmission line capable of transmitting the said optical signal, comprising dispersion shifted fibre with a length of between 100 km and 1000 km; an optical receiving station, capable of receiving the said optical signal; which comprises, between the said transmission line and the said optical receiver, a chromatic dispersion compensator. Preferably the said optical fibre transmission line has a length of between 200 and 400 km.

Abstract: A method for detecting abnormality in the morphology of erythrocytes, which comprises:(1) mixing a sample containing erythrocytes with a sphere-forming reagent;(2) introducing the sample treated in the preceding step into a detector area of a flow cytometer;(3) measuring at least one scattered light at an angle reflecting the morphology of erythrocyte among the scattered lights emitted from the sample to obtain cell distribution data; and(4) comparing the cell distribution data with cell distribution data on normal erythrocytes that were determined beforehand.

Abstract: The present invention relates to a method for instrument determination of measured variable L(t) which changes with time, the intention being to determine the maximum value of L(t) in a region with a linear reaction profile, and the time as well as the duration of the reaction time window being variable with the linear region and depending on the nature of the reaction and the reaction conditions. Specifically, the present invention relates to the determination of protein concentrations with the aid of light scatter, which is produced by specific antibodies, in homogeneous solutions. In particular, the invention relates to reactions which take place slowly and have a largely linear profile over a relatively long time, the rate of formation of antigen-antibody complexes in the linear section of the reaction (V.sub.MaxLin) being determined as the measured variable.

Abstract: The investigation, development and application of a laser-based ultrasonic inspection system to the problems of evaluating polymer/graphite composite materials has been realized. The use of lasers to generate and detect ultrasonic waveforms in materials provides a means to detect material properties remotely. The study consisted of three main aspects: 1) A confocal Fabry-Perot (CFP) based system has been devolved which uses light reflected from the CFP interferometer to derive the ultrasonic signal. This allows higher frequency components of the detected waveforms to be discerned when compared to a CFP-based system using light transmitted through the CFP interferometer. 2) Thermoelastic and ablative laser generation of acoustic pulses in polymer/graphite composite materials has been investigated. Thermoelastic generation of ultrasound occurs when thermal energy deposited by a pulsed laser creates a localized expansion in the material.

Abstract: A system that automatically aligns and stabilizes off-gimbal electro-optical passive and active sensors of an electro-optical system. The alignment and stabilization system dynamically boresights and aligns one or more sensor input beams and an output beam of a laser using automatic closed loop feedback, a reference detector and stabilization mirror disposed on a gimbal, off-gimbal optical-reference sources and two alignment mirrors. Aligning the one or more sensors and laser to the on-gimbal reference detector is equivalent to having the sensors and laser mounted on the stabilized gimbal with the stabilization mirror providing a common optical path for enhanced stabilization of both the sensor and laser lines of sight.

Abstract: In order to provide a measuring device for determining stoichiometric ratios when burning hydrocarbons by means of which stoichiometric ratios can be determined easily and reliably when burning hydrocarbons, it is proposed that a sensor be provided to detect an intensity of a first fluorescent radiation from C--H molecular fragments arising during the burning and a sensor be provided to detect an intensity of a second fluorescent radiation from molecular fragments arising during the burning and comprising only C atoms, that the sensors generate an intensity-dependent first and second sensor signal, respectively, on the basis of the first and the second fluorescent radiation, and that an evaluation circuit be provided which generates an output signal corresponding to a stoichiometric ratio from a ratio between the intensities of the first and the second fluorescent radiation.

Abstract: A rate nephelometer of the type useful in automated chemical analyzers is provided. The nephelometer includes a laser for generating a polarized laser beam having an S-wave component and a P-wave component. The beam is split by a beam splitter specially constructed so that a known proportion of one of the two polarized portions of the beam is directed to a reaction container. In the reaction container, a first polarized component of the laser beam is used in a nephelometric chemical analysis. The remainder of the laser beam passes through the beam splitter to a laser control light detector. Before the remainder of the laser beam reaches the laser control light detector, however, the polarized component which is not used in nephelometric chemical analysis is filtered out. The laser control detector uses the non-filtered portion of the laser beam to control the output of the laser.

Abstract: A sample card transport station moves a test sample card from an incubation station for the card to a transmittance and fluorescence optical station in a sample testing machine. The sample card transport station has a drive belt and an associated stepper motor. The belt supports the card from one side of the card. A ledge having a card slot is disposed above the belt. The card is snugly received within the card slot, and supported from below by the drive belt and rollers for the belt. When the motor turns the belt, the belt grips the card and slides the card along the slot to the optical stations, without any slippage between the belt and the card. This construction provides for precise control over the movement of the card.The fluorescence station has a linear flash lamp that illuminates a column of the wells of the cards simultaneously. A reference detector and dichromatic beam splitter design is used to insure that the fluorescence measurements are independent of lamp output changes over time.

Abstract: An optical fiber amplifier includes an optical filter, an optical isolator for blocking a reverse flow of a reflected light, the optical isolator including a lens coated with an integral filter having a predetermined bandwidth and an output end tab for monitoring the intensity of the output signal, the optical filter being coupled between the optical isolator and output end tab so as to only pass a specified wavelength band.

Abstract: The instant invention discloses method and apparatus for calibrating particulate emissions monitors, in particular, and sampling probes, in general, without removing the instrument from the system being monitored. A source of one or more specific metals in aerosol (either solid or liquid) or vapor form is housed in the instrument. The calibration operation is initiated by moving a focusing lens, used to focus a light beam onto an analysis location and collect the output light response, from an operating position to a calibration position such that the focal point of the focusing lens is now within a calibration stream issuing from a calibration source. The output light response from the calibration stream can be compared to that derived from an analysis location in the operating position to more accurately monitor emissions within the emissions flow stream.

Abstract: A liquid flow cytometer for counting and classification of particles such as biological cells and other microscopic particles in liquids that involves an optical system for irradiation and detection in a metering zone (7), thus enabling optical dispersion and fluorescence caused by the particles to be simultaneously detected when the particles pass the metering zone, includes in a first beam path (S.sub.1) a mirror reflector (9) with its focal point in the metering zone (7), a quarter-wave plate (8) between the metering zone (7) and the mirror reflector (9), a lens (6) with its focal point in the metering zone (7) and located on the opposite side of it together with a dichroic mirror (5) behind the lens and provided in such a manner that it gives reflection to a second beam path (S.sub.2). In the second beam path (S.sub.2) a beam splitter (4) is provided between the dichroic mirror (9) and a known per se light source (1), and produces a third beam path (S.sub.3).

Abstract: A particle analyzer includes a flow cell including first and second cells for containing an electrolyte with various types of biological particles floating therein. The first and second cells are connected to each other by a pore to allow the particles to flow from the first cell to the second cell through the pore. A first and a second electrode are provided in the electrolyte in the first and second cells respectively. A first detector detects an electric resistance between the first and second electrodes which changes according as the particle passes through the pore to generate an electric resistance signal representative of the electric resistance. A light source emits a beam of light to the flowing particle and a second detector detects scattered light from the particle receiving the beam of light to generate a scattered light signal representative of an intensity of the scattered light. A clock device clocks a period of time during which the scattered light signal is generated.

Abstract: A pathlength corrected spectrophotometer for tissue examination includes an oscillator for generating a carrier waveform of a selected frequency, an LED light source for generating light of a selected wavelength that is intensity modulated at the selected frequency introduced to a subject, and a photodiode detector for detecting light that has migrated in the tissue of the subject. The spectrophotometer also includes a phase detector for measuring a phase shift between the introduced and detected light, a magnitude detector for determination of light attenuation in the examined tissue, and a processor adapted to calculate the photon migration pathlength and determine a physiological property of the examined tissue based on the pathlength and on the attenuation data.

Abstract: An apparatus for the analysis of individual particle characteristics from an aerosol or other suspension of particles, of the type having a scattering chamber (15) with an ellipsoidal reflector (17) and an orifice leading to a rear chamber (20), and a monochromatic light source (10) adapted to transmit a collimated beam of light (11) along the main axis of the reflector (17) to impinge on a stream of the particles reflector (17), has an optical system (17, 32, 33, 34) arranged to collect light back-scattered from a particle, through a solid angle of at least 3.pi., pass the light to a a ccd video recorder (36) having a two dimensional array of a multitude of sensors.The recorder (36) is associated with a data processor (37) and with an imaging screen (35) positioned such that rays of light scattered from the particle and imaged thereon by the optical system (17, 32, 33, 34) are monotonically ordered with respect to the angle of scattering of the rays from the particle.

Abstract: A plurality of fluid condition sensors are combined together to provide a sensor cluster that senses turbidity, temperature, conductivity and the movement of a ferromagnetic object. The plurality of sensors are attached to a substrate and encapsulated, by an overmolding process, with a light transmissive and fluid impermeable material. The sensor cluster can be disposed at numerous different locations within a body of fluid and does not require a conduit to direct the fluid to a particular location proximate the sensor. In a preferred embodiment of the present invention, a circuit is provided which monitors the signal strength of first and second light sensitive components to determine turbidity and, in addition, those signal strengths are also used to advantageously determine the most efficient magnitude of current necessary to drive a light source, such as a light emitting diode.

Abstract: A method for determining whether a particular sample vial has bacterial growth includes the steps of introducing a first light into the sample vial and measuring the intensity of the reemerging light. One then introduces a second light which is different from the first light and has either a different wavelength, or is introduced at a different location than the first light. The reemerging intensity from the second light is also measured. A ratio quantity is calculated based on the two reemerging intensities, and the calculated ratio is compared to expected ratios for both positive and negative samples. It has been found that a comparison of the reemerging light intensities provides a very good indication of whether a particular sample is a positive or negative sample. Various methods and formulas for calculating the ratios may be utilized.

Abstract: The dispersion photometer described is designed particularly for the kinetic determination of total proteins and has a light source (20), an optical system, a removable optical cell (24) in the sample chamber, a stirrer, a photo-electric sensor (38) which receives light scattered forward at an angle, and an electronic processing and display unit (46) connected in series with the photo-electric sensor (38). All the elements located between the light source (20) and the optical cell (24), and between the optical cell (24) and the photo-electric sensor (38), have a coefficient of transmission or reflection in the visible region of the spectrum which is as high as possible, and do not reflect or absorb selectively.

Abstract: A pollution monitoring device including a fluid sampling chamber (21), a collimated light source (14, 15) directing a light beam (10, 11) into the chamber, a port (23) for introducing sample fluid into the chamber exposed to the light beam, a light detector cell (16) separated or shaded from the light beam and focussing apparatus (17) for directing scattered light produced by the presence of suspended particles and molecules in the chamber towards the detector. The source may be two lasers with co-linear beams or an LED. There is also disclosed a sample area of small diameter in which a light beam traverses the area across the flow path of a sample fluid and a projector projecting scattered light from particles into a light receiving zone of notional triangular shape having an included angle of less than 60.degree., to enable discrimination of particle size discrimination.

Abstract: In the method and apparatus for inhibiting a scattered component in a light having passed through the interior of an examined object, a light is radiated to the examined object, the sum of a straight advancing light component and scattered light component of the light having passed through the interior of the examined object is detected, only the scattered light component of the light having passed through the interior of the examined object is detected and the straight advancing light component is detected by an operation using the two detected outputs. In the scattered component inhibiting method and apparatus, a light modulated with a period larger than the delay of the propagating time by the scatter in the examined object is radiated to the examined object, the light having passed through the interior of the examined object is detected and the straight advancing light component is extracted by extracting a predetermined phase of the detected output.