Laser-induced chlorophyll fluorescence lifetime measurement and characteristic analysis

Abstract

A laser-induced fluorescence lifetime measurement method is presented to evaluate living status for plant growth and the environmental monitoring. A 355 nm laser is used as excitation source for exciting chlorophyll fluorescence, and the fluorescence signals are received by a photomultiplier. Because the measured signal is the convolution of the reliable fluorescence decay signals, laser pulse and instrument response function, according to their characteristics, the time-resolved measurement method is used to estimate the chlorophyll fluorescence and background signals separately; the real fluorescence decay signals are separated by combining a novel deconvolution method, and the chlorophyll fluorescence lifetime can be retrieved. Experiment shows that the method proves to be a high accuracy and real-time monitoring chlorophyll fluorescence lifetime technique; and the chlorophyll solution fluorescence lifetime is measured for different concentrations. The result can prove that the chlorophyll concentration is related to its fluorescence lifetime, and the calibration curves of chlorophyll concentration and fluorescence lifetime is fitted.