Patent ID: 6496260
Filing Date: 2002-12-17
Classification: G01J,G01N

Abstract:
A photometric device comprising:a light source for providing at least a portion of a first wavelength range, a wavelength selector that provides light of a first and a second wavelength within the first wavelength range, a first sample retainer that retains a reference liquid holder of predetermined light absorption pathlength, a second sample retainer that retains a multi-assay plate, a first light distributor that transmits substantially horizontally at least the first wavelength through the reference liquid holder, a second light distributor that transmits substantially vertically at least the first and second wavelength through sample sites on the multi-assay plate, a first photodetector that responds to the light transmitted through the reference liquid holder a second photodetector that responds to the light transmitted through the sample sites, a computational device that relates the light transmitted through the reference liquid holder and the light transmitted through the sample sites by determining the light absorption pathlength of the samples contained in the multi-assay plate from the relative transmission of the first wavelength of light through the samples and through the reference liquid holder and the predetermined light absorption pathlength of the reference liquid holder, and a heater and temperature regulator that maintains the multi-assay plate and the reference liquid holder at substantially the same temperature.