Simple and Accurate Fluorescence Lifetime Measurement Scheme Using Traditional Time-Domain Spectroscopy and Modern Digital Signal Processing

Fluorescence lifetime measurement is an essential process for evaluation and application of optical gain media. An accurate and convenient scheme for fluorescence lifetime measurement of complex emission processes with either single or multiple fluorescence lifetimes is essential. We developed a new convolution-based scheme for fluorescence lifetime measurement. The innovation of the scheme lies in a combination of convolution-based digital signal processing algorithms with a low cost and simple time-domain spectroscopic setup. The convolution-based scheme is able to achieve accurate microsecond fluorescence lifetime resolution using the spectroscopic setup with only millisecond fluorescence lifetime resolution, for both single or multiple fluorescence lifetimes. We demonstrated the performance of the scheme, both theoretically and experimentally, by measuring fluorescence lifetimes associated with complicated emission processes in bismuth-erbium-doped fibers and erbium-doped fiber.