Solid-state fluorometer and methods of use therefor

摘要

Fluorescence of a sample cell 20, 120, resulting from excitation by a diode laser 12 or a LED excitation source, 112 is imaged, optionally with a lens, 14, 114 onto a silicon photodiode detector 16, 116. An optical filter 18, 118 is placed between the sample cell and the photodiode detector to reject scattered excitation light. Output from the photodiode is amplified to produce an output voltage proportional to the quantity of fluorescence striking the photodiode detector. Since fluorescence is proportional to the concentration of a fluorophore present in a sample stream through hthe sample cell, and the concentration of the fluorophore is further proportional to a concentration of a chemical treatment agent or other additive present, then continuous monitoring of a voltage output allows real-time measurement of the amount of chemical treatment agent or other additive present in the sample stream.