Abstract: A multicolor particle analyzer and method is described. The particles which either naturally fluoresce or are tagged to fluoresce at distinctive wavelengths are caused to flow through an analyzing volume where fluorescence is excited by an impinging light beam. A tunable optical filter repetitively and sequentially passes emitted light at each of the characteristic wavelengths and the light transmitted through the optical filter is received by single detector which provides output signals representing particles at each distinct wavelength.

Abstract: A multicolor particle analyzer and method is described. The particles each of which either naturally fluoresce or are tagged to fluoresce at distinctive wavelengths are caused to flow through an analyzing volume where fluorescence is excited by an impinging light beam. A tunable optical filter repetitively and sequentially passes emitted light at each of the characteristic wavelengths as each particle travels through the analyzing volume and the light transmitted through the optical filter is received by single detector which provides output signals representative of each distinct wavelength of light emitted by the particle.

Abstract: A method of determining the volume of cells or particles is described. The method relies upon the displacement of the liquid in a liquid suspension of cells or particles. The liquid suspension is strongly fluorescent and the volume of the cells or particles is measured by measuring the reduction of fluorescent light due to the presence of cells or particles.

Abstract: A particle analyzer in which tagged particles to be analyzed are drawn through a suspended capillary tube where a predetermined volume in the capillary tube is illuminated. The illumination scattered by said particles is detected by a detector to count all particles. The fluorescent illumination emitted by tagged particles is detected and the output signals from the fluorescent detectors and scatter detector are processed to provide an analysis of the particles.

Abstract: An interactive advertising system is adapted to identify, measure and track consumer exposure to a number of different advertisements and to expose consumers to several different advertisements. The system simultaneously identifies and measures the number of consumers viewing different advertisements, while displaying different selected advertisements for viewing by the consumer. The system includes a display for displaying advertisements and other information. The system functions in either one of an idle mode, wherein potential consumers are not within a sensed proximity range, and an active mode, wherein the presence of potential consumers within the proximity range is detected. In the idle mode, the system displays programmed non-advertisement information. In the active mode, the display projects a programmed sequence of advertisements, that includes full-motion color commercials that may be interspersed with other information.

Abstract: A particle analyzer in which tagged particles to be analyzed are drawn through a suspended capillary tube where a predetermined volume in the capillary tube is illuminated. The illumination scattered by said particles is detected by a detector to count all particles. The fluorescent illumination emitted by tagged particles is detected and the output signals from the fluorescent detectors and scatter detector are processed to provide an analysis of the particles.

Abstract: Fluid sample tester assembly (12) comprises a cartridge (6) having a pressure chamber (22) and entrance port (20) connected by a passageway (24). An analyte reagent (36) is positioned along the fluid passageway so that when a liquid sample (28) is drawn through the entrance port into the passageway, the analyte reagent mixes with the sample. The sample is preferably drawn into the cartridge by temporarily reducing the volume of the pressure chamber, applying the sample to the entrance port and then returning the pressure chamber to its initial volume; this can also be done by heating the chamber, contacting the sample and then cooling the chamber. The end of the sample defines a boundary surface (30) along the fluid passageway. Positive and negative pressure is applied to the sample to cause the boundary surface to oscillate within the passageway.

Abstract: The present invention provides a method of using a reflectance-reading device to determine an initiation time point for measuring the chemical reaction of an analyte from a biological liquid sample on a test surface. The initiation time point is determined by using a device to read a reflectance of a test surface at a plurality of time points, and calculating the K/S ratio of the test surface at each time point according to the Kubelka-Munk equation. As the device continues to calculate a K/S ratio for each time point, the device monitors the rate of change of the K/S ratio with respect to time. The device then determines the initiation time point to be when the rate of change of the K/S ratio is maximal. The present invention also provides a method of measuring the concentration of an analyte on a test surface. The concentration is measured by determining an initiation time point according to the method described above and then measuring the concentration of the analyte at a variable end point.

Abstract: Fluid sample tester assembly (12) comprises a cartridge (6) having a pressure chamber (22) and entrance port (20) connected by a passageway (24). An analyte reagent (36) is positioned along the fluid passageway so that when a liquid sample (28) is drawn through the entrance port into the passageway, the analyte reagent mixes with the sample. The sample is preferably drawn into the cartridge by temporarily reducing the volume of the pressure chamber, applying the sample to the entrance port and then returning the pressure chamber to its initial volume; this can also be done by heating the chamber, contacting the sample and then cooling the chamber. The end of the sample defines a boundary surface (30) along the fluid passageway. Positive and negative pressure is applied to the sample to cause the boundary surface to oscillate within the passageway.

Abstract: A sample collection and manipulation apparatus (2), typically used for collecting and manipulating a blood sample and measuring a component of that sample with the use of a reagent or ion-selective electrodes, includes a body member (4, 6, 8) defining a thermal pressure chamber (22) and a sample port (10). A measurement chamber (26) is formed along a fluid passageway (42, 16, 24) connecting the thermal pressure chamber with the sample port. The air within the thermal pressure chamber is preheated (54, 56, 60, 62, 63/65) to reduce its density and the sample port is then placed in contact with the liquid. As the gas cools, a partial vacuum is created within the thermal pressure chamber to draw a liquid sample through the passageway and into the measurement chamber. Appropriate analyte measurement techniques, such as optical or electrochemical, can then be carried out. Applications include the testing of blood gases, glucose, hemoglobin, electrolytes, coagulation and therapeutic drugs.

Abstract: The present invention provides a compact, highly automated photometric analyzer for measuring the concentration of substances found in a fluid, typically a blood sample or other body fluid sample taken from a patient. The operator places a small quantity of the sample into a special rotor and then loads the rotor into the analyzer. The analyzer accepts the rotor, centrifuges and dilutes the sample, and distributes the sample into a plurality of cuvettes near the outer edge of the rotor. Some of these cuvettes hold reagents which react with the sample. The analyzer then measures light absorption within the sample at a number of preselected frequencies. According to the present invention, a pair of specially designed apertures direct light from the sample through a plurality of beam splitters, interference filters, and associated photodetectors. The system also includes means for performing automatic calibration and error checking functions.