Apparatus for and method of measuring flourescence lifetime

摘要

A method of measuring fluorescence lifetime includes illuminating a sample containing at least one fluorophore with light to excite fluorescence and switching the intensity of the excitation light repeatedly between a first intensity I₁ and a second intensity 1₂. Emitted light caused by fluorescence of the sample is detected and a detected light signal is generated. The detected light signal is switched repeatedly to divide it into first and second portions, and the amount of light detected during each of the first and second portions is measured to obtain a first emitted light value S₁ and a second emitted light value S₂. The fluorescence lifetime is determined from the first and second emitted light values S₁ and S₂.