Abstract: Mixtures containing homogeneously-sized particles with a minimum concentration of agglomerates or larger particles are desired in various manufacturing processes such as, for example, in the manufacture and use of chemical mechanical polishing slurries, food emulsions, pharmaceutical products, paints, and print toner. The method disclosed herein provides these industries with an accurate and efficient method of screening such mixtures for such agglomerates and large particles. The method generally includes preparing a suspension of the mixture in an electrolyte, wherein the suspension includes a specified concentration of small particles per unit of electrolyte. The method further includes passing the prepared suspension, and a plurality of the particles therein, through an aperture of a device capable of characterizing particles according to the Coulter principle to obtain data on the particles.

Abstract: Mixtures containing homogeneously-sized particles with a minimum concentration of agglomerates or larger particles are desired in various manufacturing processes such as, for example, in the manufacture and use of chemical mechanical polishing slurries, food emulsions, pharmaceutical products, paints, and print toner. The method disclosed herein provides these industries with an accurate and efficient method of screening such mixtures for such agglomerates and large particles. The method generally includes preparing a suspension of the mixture in an electrolyte, wherein the suspension includes a specified concentration of small particles per unit of electrolyte. The method further includes passing the prepared suspension, and a plurality of the particles therein, through an aperture of a device capable of characterizing particles according to the Coulter principle to obtain data on the particles.

Abstract: An apparatus and method in which a still image, or still images, are obtained of a plurality of particles suspended in a fluid medium. Each still image is transferred to an image analyzing unit that measures a set of dimensional characteristics per particle for particles appearing in the image and determine an occurrence characteristic for particles having a matching set of dimensional characteristics. Preferably, a three dimensional representation of the characteristics is displayed in real time. More preferably, the displayed three-dimensional representation is continuously updated and further entries are accumulated on the display as image analysis is performed. The display provides information to a viewer enabling the viewer to determine a shape distribution of the particles within the suspension even when multiple particle shapes are present.

Abstract: A particle sizing method and apparatus of the PIDS type uses randomly polarized radiation to irradiate a particle sample. Portions of the resulting side scattering pattern are decomposed to simultaneously produce, for each decomposed portion, first and second linearly polarized beams of radiation in which the respective planes of polarization of the two beams are mutually perpendicular. Each of the polarized beams is focused onto a photodetector, and the respective photodetector outputs are differentiated to provide PIDS signals that are useful in calculating a particle size distribution for the sample.

Abstract: A particle sizing method and apparatus of the PIDS type uses randomly polarized radiation to irradiate a particle sample. Portions of the resulting side scattering pattern are decomposed to simultaneously produce, for each decomposed portion, first and second linearly polarized beams of radiation in which the respective planes of polarization of the two beams are mutually perpendicular. Each of the polarized beams is focused onto a photodetector, and the respective photodetector outputs are differentiated to provide PIDS signals that are useful in calculating a particle size distribution for the sample.

Abstract: An apparatus and method in which a still image, or still images, are obtained of a plurality of particles suspended in a fluid medium. Each still image is transferred to an image analyzing unit that measures a set of dimensional characteristics per particle for particles appearing in the image and determine an occurrence characteristic for particles having a matching set of dimensional characteristics. Preferably, a three dimensional representation of the characteristics is displayed in real time. More preferably, the displayed three-dimensional representation is continuously updated and further entries are accumulated on the display as image analysis is performed. The display provides information to a viewer enabling the viewer to determine a shape distribution of the particles within the suspension even when multiple particle shapes are present.

Abstract: This invention provides an improved particle-enhanced assay for determining the concentration of any of a wide range of analytes with a high degree of specificity, accuracy, and sensitivity, primarily by improving the measurement of particle aggregates. Analyte concentration is determined by effecting a particle-enhanced reaction in an assay medium and measuring the distribution of different sized aggregated particles in the reaction mixture by polarization intensity differential scattering. The particle size distribution is then compared with a standard curve to determine the concentration of the analyte in the sample.