Abstract: The invention relates to a method for fluid separation of whole blood as a mixture of liquids into individual, differently-colored blood constituents, which blood is packed in flexible containers, in particular bags, wherein the bags are connected to one another with an at least partially light-transparent connection, in particular a flexible tube, and wherein the blood constituents are forced to flow from one container through the light-transparent connection into another container, in particular for the separation of concentrated thrombocytes from buffy coat, as well as to a device for performing the method.

Abstract: A colorimetric red blood cell sensor provides an automatic system for deting and preventing the further mixing of red blood cells and plasma. The sensor includes a processor that controls blue and red light sources so that they collectively generate pulsed blue and red light signals that are directed through blood serum held in an optically transparent container. The red and blue signals are 180 degrees out of phase, and hence staggered, with respect to each other. A photodetector system detects the pulsed red and blue light signals and generates output signals representing the intensities of the staggered signals received by the photodetector system. A microprocessor determines the ratio of the intensities of the red and blue light signals detected by the photodetector system. If the ratio exceeds a limit, the microprocessor generates a fluid control signal that prevents further mixing of red blood cells and plasma.

Abstract: A colorimeter for measuring colour of process medium comprising two light sources and two detectors both light sources being arranged to emit a beam through the process medium and the windows adjoining the process medium to both detectors. In order to achieve a solution functioning reliably the windows adjoining the process medium at both light sources are formed from a triangular prism, the two surfaces of which being at an angle to each other, are arranged to divide the beam arriving from the light source into two beams travelling in different directions so that both beams proceed to the process medium through the same part of the window surface formed by a third surface of the prism. Mirror surfaces arranged to gather radiation arriving form both light sources to a sensor of the detector are formed at both detectors.

Abstract: A method and an arrangement by which separating liquid streams, such as occur for example in cell sorters, are monitored automatically. An image of the separating liquid streams is recorded and the position of a separation point at which the drops separate from a column of liquid is found using image analysis methods. Various solution possibilities are indicated for the suitable preparation of the image information for easier processing.

Abstract: Disclosed is an apparatus for fluidic separation systems comprising a microfabricated conduit including a usefully long optical pathlength. The provision of a usefully long optical pathlength in the apparatus greatly improves the sensitivity of detection of separated analytes without compromising the resolving power of the apparatus.

Abstract: A brewed beverage maker, such as a coffee maker, is provided having an automatic concentration control system. An optical feedback system is employed for controlling the concentration of brewed beverages such as coffee and tea. In preferred embodiments, this invention employs a light beam that is passed through the beverage as the beverage is being made to determine the concentration of the beverage. A control system compares the measured concentration to a desired concentration and controls the flow of water through a filter basket containing coffee, tea or the like.

Abstract: In a method of measuring optical characteristics of a component in a liquid impregnated in a porous material with no affection by the porous material, a light beam having an absorbable wavelength which is absorbed by the component in the liquid and a light beam having a wavelength which is longer than the absorbable wavelength are projected to the porous material, and a quantity of light having the wavelength which is absorbed by the component in the liquid is compensated by a quantity of transmitted light having the wavelength longer than the absorbable wavelength.

Abstract: An optical detector for flowing sample comprises a light condenser for condensing a diverging monochrome light, a flow cell arranged in the course of convergence of the converged light beam, and a sample-side detector for receiving a sample-side light. Such a construction makes it possible to correct delicate changes of the light axis due to intensity, position, temperature changes of the light source, density change of the flowing liquid, and any change of other causes effectively for stable sample analysis without difficult optical adjustment.

Abstract: An analytical system for analyzing a fluid sample is disclosed. The analytical system includes a microcolumn for conducting the fluid sample, a light source for delivering light through the microcolumnar wall into the microcolumn near the outlet end of that microcolumn, and an optical fiber aligned with the microcolumn to detect light that radiates from the fluid sample without passing through the microcolumnar wall. The microcolumn has an inlet end and an outlet end. A light-inlet end of the optical fiber is nonfixedly coupled to the outlet end of the microcolumn. As the fluid sample is driven from the inlet end to the outlet end of the microcolumn, a light of a suitable wavelength is directed at the microcolumn near its outlet end to cause light interaction with the fluid sample. As a result, light radiates from the fluid sample. This light is collected by the optical fiber to provide information on the presence or quantity of an analyte in the fluid sample.

Abstract: A device for detecting a conduit and for determining at least one characteristic of its content includes a seat for housing at least a portion of the conduit. The seat has first and second zones which are opposite each other with respect to a recess intended to receive the conduit. A light emitter is arranged in the first zone, and has a preferential emission direction oriented towards the recess. A receptor sensitive to the light emitted by the emitter also has a preferential reception direction oriented towards the recess. A first deflector deflects light in the direction of the first zone when a conduit containing a substantially transparent liquid is engaged in the seat.

Abstract: A spectrophotometer which accommodates a self-contained sample module. Sample modules are interchangeable and can be readily inserted into, or removed from, the spectrophotometer without tools. Guides in the spectrophotometer assure that the modules are properly aligned when inserted. The module houses the sample(s) to be tested. Sample cell holders may be removed from the module and replaced with other cell holders. When the module is inserted into the spectrophotometer, optical alignment, mechanical alignment, proper electrical connection and software interface are all achieved in one common installation procedure for all sample modules.

Abstract: A minute flow path is filled with liquid so that the liquid may be supplied from an accumulating portion. Energy is imparted to the liquid exposed outwardly of an opening in the flow path by a heat generating element or by energy application to thereby heat and gasify the liquid. Thereupon, the liquid is supplied by an amount corresponding to the gasified liquid by capillary phenomenon through the flow path, and gasification is continuously effected, whereby a flow free of pulsating flow can be formed in the flow path.

Abstract: An optical detector for use in liquid chromatography systems or capillary electrophoresis systems comprises an optically transparent detector body through which an analyte channel extends, a fluid containing the analyte being adapted to be guided through said analyte channel. In order to increase the detection sensitivity, the light path between a light source introducing light and an optoelectric sensor element of the liquid chromatography system or capillary electrophoresis system is constructed as a Bragg waveguide structure extending at least along a sublength of said analyte channel essentially in the channel direction.

Abstract: A colorimeter is provided in which a measuring pipe diverts a sample of a substance off of a production line into a measuring chamber. A series of cut-off valves control the quantity of the sample accumulated in the measurement zone to ensure sufficient amount for analysis. An optical head having three concentrically aligned light projectors projects light onto the sample. Light reflected off the sample, the wavelength of which indicates the sample's color, is collected by an optical collection system and sent to a color analyzer for comparison with a predetermined color. The measurement chamber is provided with temperature, humidity and level sensors to account for shifts in wavelength due to these parameters.

Abstract: A method for calibrating an automatic chemical analyzer whereby an improved baseline value is calculated. The analyzer uses a photodetector to detect the amount of light passing through a flow cell and correlates this value to the amount of analyte present in a sample solution. In the preferred embodiment, silica is the analyte under investigation. A baseline solution of a specified (preferably zero) analyte concentration, or a sample solution of unknown analyte concentration, is introduced into a chemical module after chemical reagents have reacted with themselves to form a color complex. The resulting solution is passed to the photodetector which determines the amount of analyte present. This value corresponds to the analyte contaminants within the reagents and can be subtracted out by further calculations.

Abstract: A method and system achieving the results of a conventional titration without the need to chemically dilute a sample. Such a result is accomplished by providing a plurality of calibration standards, each containing a different known concentration of a visualizable material. The visualizable material contained within each calibration standard is then visualized (the parameters of the visualization forming a setting). The visualization is then altered by adjusting at least one parameter of the visualization until the point where the visualizable material within each calibration standard can no longer be visualized within the solution. The visualizable material within a sample solution having an Unknown concentration of the visualizable material is then visualized using settings corresponding to the plurality of calibration standards to generate a number of modified visualizations. (Each modified visualization corresponds to the concentration of the standard to which it relates).

Abstract: A flow cell for use in optical measuring systems particularly suited for use with liquid food products is provided. The flow cell is manufactured from a single unitary piece of synthetic resin which is transparent to light in the near infrared range. Because the flow cell is constructed from a single piece, the interior surface is continuous and the presence of undesirable cracks or crevices is avoided.

Abstract: An absorption meter determines concentration of chlorophyll a and pheophytin in liquids. Particularly, an immersible absorption meter has a light source, a reflective flow tube, a signal detector, and means for determining the difference between the absorption coefficients at a first wavelength and a second wavelength. The light source may further include a plurality of filters and a selector that selects the filters. The concentration of substances in liquids is determined by measuring the absorption of light at a first wavelength and at a second wavelength, determining the difference between the absorption coefficients for the first and second wavelengths, and converting this data into concentrations.

Abstract: A dual-wavelength absorption detector is provided. The detector includes an electronics section, a three branched optical guide and a detector-cell. Each branch of the optical guide has a plurality of fibers, and at one end the branches are separated and connected to different portions of the electronics section. Two of the three branches are terminated next to LEDs having different wavelengths, a measuring wavelength and a reference wavelength. The third branch is terminated next to a photodetector. At the opposite end of the optical guide the three branches are combined to form a common end which is terminated within the detector-cell. The detector-cell includes a continuous-flow sample cell connected to a sample line. Within the detector-cell, the common end's fiber ends are held at a fixed location on one side of the sample cell with a concave mirror being located on the opposite side.

Abstract: An optical interface coupler for coupling a flow cell to an optical absorption analyzer. The flow cell and analyzer are operable to transmit light through a fluid flowing through a chamber within the cell and analyze the transmitted light for determining certain optical properties of the fluid. The cell includes a first port through which light from a first fiber optic cable is transmitted to the chamber and a second port through which transmitted light is received and transmitted to a second fiber optic cable connected to the optical absorption analyzer. The optical interface coupler comprises a housing and a lens. The housing is releasably attachable to the cell at one of the first and second ports and defines an optical pathway therein. A cable port is in the housing for receiving one of the first and second fiber optic cables, and is in optical communication with the optical pathway.

Abstract: The flow cell system and method of the present invention for constructing and operating a light scattering test stand enables close reproducible tolerances to be achieved and automatically ensures the mutual alignment of the structures utilized to maintain stability. Pins and bosses are utilized to maintain alignment of the cell assembly with the read head. The flow cell assembly is held down in the read head independently of the stray light cover. The design of the present invention enables precision alignment reproducibility and ease of use.

Abstract: An injection port for injecting a sample, an accumulation portion for accumulating the injected sample having a reagent carrier enclosed, a flow passage portion, having a light receiving element at a measuring position located halfway thereof, for passing a reaction fluid having reacted with the reagent in the accumulation portion therethrough, a micro-pump having a feed action of the sample fluid within the flow passage portion and which is a heat generating element provided near a nozzle downstream of the measuring position of the flow passage portion are formed integrally and intensively as a cartridge by a producing method including a semiconductor fabrication process.

Abstract: The concentration of a colorant in a stream of molten polymer is measured by inserting a probe adjacent to the stream. The probe has integral therein collection means and illumination means. The steam is illuminated with the illumination means to cause electromagnetic radiation to be reflected from the molten polymer. The electromagnetic reflectance is collected, transmitted to a measurement device remote from the molten stream and quantified as a function of the concentration of the colorant.

Abstract: A chemical sensor and method for in-line chemical analysis including a body having a central cavity. The body also has a pair of openings through it to the cavity. A porous plug, such as a ceramic frit, is sealed into each of these openings so that there is a space between the plugs in the cavity. A vent passageway through the body to the cavity is also provided. A pressurized sample is flowed through one porous plug into the cavity while a pressurized reagent is flowed through the other porous plug into the cavity. A component of interest of the sample reacts with a reactive component of the reagent in the cavity to produce a reaction product. The reaction product is analyzed in the cavity by, for example, absorption spectroscopy. As fresh sample and reagent flow into the cavity, the reaction products flow out of the cavity by way of the vent passageway.

Abstract: A dual wavelength optical sensor for measuring chemical properties of a particular quantity, the optical sensor including a sensor probe having a thin sensing film whose optical characteristics are responsive to the chemical properties of the measured quantityThe United States Government has certain rights in this invention pursuant to Contract No. ITA87-02 between the U.S. Department of Commerce and Iowa State University.

Abstract: In order to improve a signal-to-noise ratio of an optical detector with a light source and a photodetector of ordinary performance, light is applied from an ultraviolet lamp 6 which is provided on one side of a capillary cell 4 while light generated from the capillary cell 4 is received by an array photodetector 14 provided on the other side thereof. A lens 18 makes positions on the capillary cell 4 to correspond to those on the array photodetector 14. A data processing part 20 temporarily stores corrected and incorporated detection outputs, and calculates integrated averages while displacing time bases so that those of the same sample portions are overlapped with each other.

Abstract: An analytic separation arrangement includes a system of tubes including a separation zone, preferably a separation column, which tubes upstream the separation zone are connected with reservoirs for a carrier and a chemical sample to be seperated and analyzed, and downstream the separation zone are connected with a waste container for the carrier containing the sample and also are connected with transporting means for the carrier and the sample. The tube system is associated with an optical detector for monitoring changes in the absorption, in the fluorescence or in the optical activity of the carrier when it is transported through the tube system and past the optical detector, which is arranged in the path of the carrier behind the separation zone but in front of the waste container. Between the separation zone and the optical detector there is arranged in the path of the carrier a refractive index equalizing unit.

Abstract: The sensor system monitors solutes in a liquid stream by analyzing the amount of light absorbed in a liquid in a particular wavelength band. The sensor system is arranged for selectability of the type of fiber used for transmission and adjustability of the liquid gap length in the liquid so that individual installations can be arranged with optimum characteristics for sensing particular chemical species in solution by absorption spectroscopy.

Abstract: An apparatus for enhancing signal to noise ratio in the detection of electromagnetic radiation traversing a capillary tube includes a ball lens and a holding element for holding the ball lens and the capillary tube, the holding element having an aperture so that the aperature and the lens together define an optic axis. The holding element is configured to hold the capillary tube such that the center of the capillary tube traverses the optic axis. The lens has a focal length and is held at such a position relative to that focal length by the holding element such that electromagnetic radiation incident on the aperature is focussed to pass radially through the capillary tube. Thus, the effective path length is 100% of the inside diameter of the capillary tube.

Abstract: An automatic chemical analyzer includes containers for chemical reagents, a standard (full scale) solution and a baseline solution. An overflow sampler provides a test sample having a chemical concentration to be measured. Computer controlled valve means connect either the baseline solution, standard solution or test sample to an output tube, and a peristaltic pump couples the reagents and the liquid in the output tube to a chemical module where the chemical reaction takes place. The output of the chemical module is coupled to a flow cell in the form of a stream of liquid segments separated by air bubbles. Light at a selected optical frequency is passed directly through the flow cell to a photodetector the output of which is converted to digital form by a computer which stores baseline and full scale values corresponding to the color values of the liquids in the baseline and standard containers.

Abstract: Apparatus and method for determination of concentrations of a substance in solution in a sample by determining the time between when the substance first appears and when it disappears. The time between the appearance and the disappearance of the substance is used to determine the concentrations of the substance in a sample. The apparatus includes many elements of a flow injection analysis system but also includes a very important stirred dilution chamber that enables the apparatus to use a simplified detection system that is capable of being used over a wide range of sample concentrations. The apparatus can include a microwave digestion system and in one embodiment a continuous flow microwave digestion system.

Abstract: A sample supply device includes first and second sample supply means for independently receiving respective samples via a common channel and for supplying the samples to an inspection position. The device is controlled so that the second sample supply means performs a sample receiving operation and/or a washing operation with the channel, while the first sample supply means supplies the sample to the inspection position. A sample inspection apparatus inspects the sample at the inspection position principally using an optical method.

Abstract: An apparatus for measuring light absorbance in a liquid sample which includes a light source for directing light into a sample cell, a cylindrical sample cell, a light detector for measuring intensity of light emitted from the cell and focussing means for forming a tapered light beam to pass through the sample cell. The tapered light beam can be either a diverging beam or a coverging beam through the cell. When the light beam is a diverging beam, a masking means is positioned downstream of the cell to assure that any light striking the cell wall is not directed to the light detector.

Abstract: A sample inspecting method and apparatus serially accumulates a plurality of liquids into a liquid path. The liquid path is pressurized to supply the accumulated liquids to an inspection station, wherein particles of selected liquids are inspected. A gas can be incorporated between each liquid and detected to discriminate between different sample liquids and washing liquids.

Abstract: Optical analytical instruments to determine a physical parameter of a fluid, and methods of operation of such instruments, are shown. These employ a source of suitable optical radiation, a detector means, means defining a zone for the fluid, means defining an optical path from the radiation source through the fluid zone to the detector means, and reading and control circuitry. At least two readings of optical energy that has been influenced by the fluid are taken without there having occurred substantial change to the fluid. During one of the readings a filter of known absorbance is included in the optical path so that the respective reading represents a calibration reading.

Abstract: Method for making a probe with a plurality (one or more) of optical fiber sensors containing colorimetric chemical indicators in gaps in the fibers, the fibers bent to provide good light transmission qualities. Apparatus for making a probe with a plurality of such optical fiber sensors. A probe with a plurality of such optical fiber sensors. A vacuum chuck for holding the ends of such fibers.

Abstract: A light absorption detector includes a light source substantially adjacent a window of a chromatogrpahic flow cell. The flow cell is defined by a housing member which also includes a photo-sensitive detector.

Abstract: There is disclosed herein a cell assembly for a spectrophotometric analysis or detection of a substance within a small sample volume. The assembly includes a cell body with a small sample bore, along with windows engaging said body to allow radiation to pass through the sample bore and the windows. A sealing arrangement is provided for each window via a sealing washer which is loaded by two means. An inner portion of the sealing washer engages the window and is loaded by a first spring loaded assembly, such as a Belleville washer and plunger. An outer portion of the sealing washer is separately loaded by a ring pressed against the cell body.

Abstract: There is disclosed herein a cell assembly for use in spectrophotometric analysis or detection of a substance within a small sample volume, such as in a capillary sample cell. The assembly comprises a transparent lens having the shape of a ball, sphere or cylinder, referred to as a "ball lens," and which is placed in direct contact or close proximity to the exterior wall of the capillary cell. This lens and cell are mounted together, any may form a removable cell assembly. The small volume may be contained within the ball lens itself. The ball lens serves to concentrate and direct light into the capillary cell. The arrangement also significantly reduces the sensitivity to alignment of replaceable cells thereby permitting easier mounting and replacement of such cells.

Abstract: A sheath flow type flow-cell device for plow-cytometer which comprises a first inlet for sheath fluid, a flow passage communicated with the first inlet and contracted toward downstream, the flow passage having a substantially rectangular cross section, a straight capillary flow passage connected to the flow passage downstream thereof, the capillary flow passage having a substantially rectangular cross section, a second inlet for sample fluid, a nozzle communicating with the second inlet and opened within the flow passage in the same direction as the flow direction of the straight capillary flow passage, a discharge port provided at a terminal end of the straight capillary flow passage, and flow regulating means for regulating the flow of the sheath fluid in the straight capillary flow passage to be a laminar flow having a gradient of flow velocity.

Abstract: A particle detector for detecting particles of blood components in an electrolyte employs a minute hole through which a fixed quantity of the material is drawn. Electrodes inside and outside the detector pass an electric current through the minute hole. When a particle passes through the hole, it partially blocks the hole, whereby a sharp change is experienced in the amount of current passing through the electrolyte. A syringe fluid path in the detector enters the fluid path for the test fluid at right angles thereto. The inside electrode is disposed in the syringe fluid path near its junction with the fluid path for the test fluid. A colorimeter is placed in series with the flow of the test fluid to measure the concentration of hemoglobin in the test fluid. Automated control of the particle detector is provided by a plurality of cams driving a corresponding plurality of pistons.

Abstract: For use in a spectrophotometry or spectrofluorimetry system, where a fluid to be analyzed, is passed into or through a tube having at least one branch, a plastic device insertable into said branch, said device comprising a tubular plastic member the inner end of which is closed by a transparent transverse end wall, extending into the tube branch and within which an end of a fiber optic cable is removably secured with such end disposed in facing engagement with the inside of said wall, and a detector cap defining a chamber to hold some of the fluid or a dye color reactive to such fluid, is secured on the opposite side of the end wall. The tubular plastic member is removably securable in, and closes the tube branch.

Abstract: A process cell (1) for the analysis of liquids, particularly cloudy ones with high light absorption, has a measuring chamber (2) through which flows said liquid, which has two windows (3) lying at a short distance opposite each other for the passage of the measuring light. The latter are held in holding devices (4) which are supported by a common frame (5), which is sufficiently movable relative to the cell housing (6) to be able to perform heat movements. The frame (5) and the holding devices (4) consist of a material with essentially the same coefficient of thermal expansion, so that changes in length of the holding devices (4) occurring upon temperature changes can each time be compensated so that the distance between the two windows (3) practically does not change and thus no changes in the measuring results determined by temperature fluctuations occur.

Abstract: A column holder for on-column photometric detection capillary liquid chromatography incorporating a body and a pair of straight edges attached to the body. The straight edges can be conveniently made from a razor blade. The body has two passageways through it that are transverse and intersecting. The first passageway is dimensioned so that a capillary column can be slipped into it or removed from it by hand. The other passageway is for the passage of a light beam from a liquid chromatography photometric detector. The straight edges are slightly separated to form an optical slit in front of the capillary column and are securely clamped to the body of the column holder. A capillary column can be removed from the column holder and be replaced with another capillary column without damaging it and without the necessity of repositioning the slit.

Abstract: The present invention relates to a split stream flow cell which is used for a UV detector of liquid chromatography and in which a UV light for detecting absorption of the light is transmitted through a sample solution flowing in the cell. It is an object of the present invention to reduce the influences of both the flow effect and the liquid lens effect without cell volume being made too large. To this end, a split stream flow cell of the present invention comprises a split flow channel (12) which passes through a cell block (10) and which has a central portion communicating with an inlet channel (18), both ends communicating with an outlet channel (38), and both sides symmetrical with respect to the central portion, the diameter thereof being increased from a given position in the central portion toward both ends.

Abstract: A flow cell for high performance chromatography, in which the measuring chamber is formed by a bore (12) in a plate (11) and the supply and discharge ducts are formed by bores (13, 14) in the plate (11) communicating with grooves (16, 18) in the plate surfaces (15, 17), the grooves being covered by transparent plates (19, 20) bonded on the plate surfaces, and thus forming closed ducts.

Abstract: Monitoring concentration of components of blood flowing through a flowpath including flowing the components through a transparent channel, directing light to the channel along an axis intersecting the channel, detecting light passing through the channel along the axis, detecting light scattered off of the axis, and determining concentration of components based on the light passing along the axis and/or the light scattered off of the axis. Also disclosed is a movable cover to block ambient light from a photodetector after mounting of a removable transparent flow channel.

Abstract: An apparatus for microscopically analyzing fluids consisting of subsystems for providing fluid flow and for acquiring and displaying an image. The fluid flow subsystem pumps a portion of the fluid sample from a sample container to a flow-through cell, where a thin planar portion of sample is presented for viewing. The flow-through cell includes a three-part lamination, the two outer members being generally flat and the center member having a display chamber cut out of its central portion. The fluid flow subsystem also includes means for washing the subsystem between samples, by pumping a quantity of solvent through the flow-through cell, the pump and associated tubing. A light beam is passed through the flow-through cell, enabling a video camera to acquire a magnified image of a portion of the sample, which image is displayed on a monitor.

Abstract: A carbon monoxide detector comprises a single monochromatic infrared source which is arranged to alternately direct light through two separate gas-containing test chambers. The first chamber is supplied with gas to be tested which has an unknown carbon monoxide content. A catalytic burning chamber is connected between the first and second chambers to receive gas from the first chamber, burn the carbon monoxide in the gas to carbon dioxide and supply the carbon monoxide free gas to the second chamber. A single infrared light detector is provided for receiving light as it comes alternately from the two chambers. The light from the two chambers is compared to determine the amount of carbon monoxide present in the gas of the first test chamber. Since the same background gas is provided in both chambers and only a single infrared source and detector are utilized, inaccuracies due to differences in background detection, infrared source intensity and infrared detector sensitivity are overcome.

Abstract: This invention relates to an absorbance detector particularly adapted to liquid chromatography testing. In modern chromatography techniques, light is focused within a small capacity test sample cell, and an optical system is provided to measure the absorbance of various frequencies of light to thereby identify the existence of selected compounds. Inaccuracies of presently available detecting devices result since localized heating within the test cell generates localized index of refraction variations which refract the light in a random fashion such that it is not sensed by the detector. Additional distorting effects are caused by imperfections in the optical surfaces of the system and turbulence due to fluid flow within the sample cell. In accordance with this invention, an appropriate phase conjugator in the form of a retroreflective array is placed in the path of light exiting the sample cell.