Patent ID: 7361472

Claim:
A method for providing an extended dynamic range in an analyte assay that uses scattered light from light scattering particles at one or more assay sites as signals, said method comprising: (a) detecting a first set of integrated scattered light intensity signals from light scattering particles at one or more assay sites with a sensor having a dynamic range, wherein the integrated scattered light intensity signal collected from at least one assay site exceeds the dynamic range of the senor; (b) applying at least one optical filter having an optical density to provide a reduced-intensity integrated scattered light signal that does not exceed the dynamic range of the sensor, said reduced intensity scattered light signal is from the at least one of said one or more assay sites in (a) that produced an integrated light scattering signal that exceeded the dynamic range of the sensor; (c) detecting a second set of integrated scattered light intensity signals from the light scattering particles at said one or more assay sites in (a) with the sensor, said second set comprising the reduced-intensity integrated scattered light signals of step (b); (d) converting the reduced-intensity integrated scattered light signals in (c) to a scaled signal using a predetermined conversion factor related to the optical density of the optical filter; and (e) combining the scaled signal with the first set of integrated scattered light intensity signals to provide an extended dynamic range.