Multiple wavelength light source for colorimetric measurement

摘要

A colorimetric wet chemistry analyzer (200) for determining a concentration of an analyte of interest in a sample is provided. The analyzer (200) includes a reaction chamber (118) configured to receive the sample and facilitate a reaction that changes a color of the sample based on the concentration of the analyte of interest. A photometric (122) cell is operably coupled to the reaction chamber (118) to receive the sample and direct illumination therethrough. The photometric cell (122) has a first illumination (114) source configured to provide illumination at a first wavelength through the photometric cell (122) and a second illumination source (202) configured to provide illumination at a second wavelength through the photometric cell. The second wavelength is different than the first wavelength. A photo detector (116) is configured to detect illumination passing through the photometric cell (122). A controller (102) is coupled to the first illumination source (114), the second illumination source (202) and the photo detector (116) and is configured to provide an indication of concentration relative to the analyte of interest based on a signal from the photo detector (116).