Patent ID: 6310337
Filing Date: 2001-10-30
Classification: G01J,G01N

Abstract:
A method of detecting an optical change in a series of test assays producing detectable results at varying efficiencies, the method comprising the steps of:a) selecting a test assay from said series, said selected assay having a known end-point photoresponse efficiency and a known filter center wavelength;b) providing a variable-intensity flash lamp illuminator comprising a lamp, a set of multiple filters with pre-selected center wavelengths assigned to particular assays, and a circuit for activating said lamp and comprising a capacitor, a power source, and a variable output voltage converter connected to said source and having its variable voltage output connected across said capacitor, said lamp and said filters providing a known level of system efficiency as a function of the center wavelength of the filter;c) providing a predetermined relationship of levels of illuminating intensities from said lamp as a function of photoresponse efficiencies of said assays and said system efficiencies, in which the photoresponse efficiencies of said assays are inversely proportional to the lamp intensities and said intensities are proportional to the square of the voltages applied to said lamp;d) selecting from said relationship a voltage applied to said lamp, and hence an intensity of the lamp, that corresponds to said known photoresponse efficiency of the assay selected in step (a) and its system efficiency based upon the filter center wavelength for said assay; ande) thereafter exposing said assay to said selected illuminating intensity, so that less intensity is used for assays having either higher photoresponse efficiencies or center wavelengths with a higher system efficiency, or both, than is used for worst-case efficiency assays.