Abstract: A method and apparatus for detecting cataractogenesis is disclosed. Quasielastic light scattering data are collected from the lens of an individual to be tested for cataractogenesis. The data are collected from the lens and are processed by an autocorrelator. The data from the autocorrelator are then fit to an autocorrelation function having a component which has a second derivative less than or equal to zero. This autocorrelation function has been found to change predictably with the individual's age and, accordingly, is useful in detecting and determining the degree of cataractogenesis in the individual.

Abstract: A diagnostic assay module for analytical procedures in which an optical signal developed by interaction between a component in a sample fluid, such as an analyte in a biological fluid, and one or more reagents in a resilient assay element is read by optical means. The module includes a first member having one open side and a second member adapted to close the open side of the first member against a resilient assay element. The area of the assay element to which the sample fluid is applied and wherein the optical signal developed by the interaction of the sample component and the reagent(s) in the assay element is read is maintained in a substantially horizontal orientation by flexure developed between complementing ramp surfaces on the respective first and second members.

Abstract: A low cost optical system which incorporates a low ultraviolet output tungsten halogen light source and solid state photodetectors and circuitry in such a way as to provide reliable fluorometric test results. The attainment of reliable results using such components is made possible by incorporating highly ultraviolet transmissive optics to maximize ultraviolet light throughput and by using solid state circuitry together with a filter wheel having both light blocking and light passing regions in a manner which fully accounts for noise and dark signals associated with solid state photodetectors.

Abstract: A low cost optical system which incorporates a low ultraviolet output tungsten halogen light source and solid state photodetectors and circuitry in such a way as to provide reliable fluorometric test results. The attainment of reliable results using such components is made possible by incorporating highly ultraviolet transmissive optics to maximize ultraviolet light throughput and by using solid state circuitry together with a filter wheel having both light blocking and light passing regions in a manner which fully accounts for noise and dark signals associated with solid state photodetectors.

Abstract: This invention provides a means for determining the concentration of any of a wide range of antibody or antigen molecules with a high degree of specificity, accuracy and sensitivity. Antigen or antibody concentration is determined by effecting an agglutination reaction in a liquid medium and determining the cluster size distribution of agglutinated particles by optical pulse particle size analysis. The measured cluster size distribution then is compared with a standard quantitative relationship between the cluster size distribution and concentration of the antigen or antibody being tested. By this means one may specifically ascertain the absolute concentration of the antigen or antibody in question in the sample being analyzed. In addition to detecting antigen or antibody molecules, the process of this invention can be used to determine the concentration of any substance capable of specifically promoting or inhibiting an agglutination reaction such as viruses, white blood cells or the like.

Abstract: A system for determining the cluster size distribution of submicron-size particles in a solution by optical pulse particle size analysis is provided. The system comprises a laminar flow cell having a translucent chamber, means for passing a sheath liquid and a sample liquid through the chamber, a light source and means for focusing the beam of light onto the chamber of the flow cell, a collecting lens, means for limiting collected light to a low angle, a stop, an iris, a light sensor and a means for processing the light signals. The system employs a combination of improved features which allows ultra-sensitive measurement of the cluster size distribution of particles, and can reliably detect as few as three dimers for every 10,000 monomers of micron size particles.