Time resolved fluorescence measurements allows the determination of excited state half-life of substances. In the case of the Fluorotron, these may be endogenous substances such autofluorescence in the crystalline lens, or they may be substances introduced by the investigator.
The excited state half-life of a substance may be used for identification, or it can be used to ascertain information about the environment around that substance.
For instance, certain ions in solution with fluorescence compounds may act as quenchers that reduce their effective excited state half-life.
Other substances such as glucose may also be measured using FRET sensors that rely on fluorescence quenching.
Select References:
Time Resolved Ocular Fluorometer. SBIR Grant R44EY014517.
Photomultiplier tube with dynode modulation for photon-counting. United States Patent Number US7,332,700 B2.