title: [The analysis of sinusoidal modulated method used for measuring fluorescence lifetime].
abstract: This paper has built a system with a sinusoidal modulated LED as the excitation source. Such exciter was used upon the sample Eu2 L'3 x nH2O (L' = C4H4O4). Both the excitation light and the 5Do-7F2 emission of Eu3+ ion were measured. Fluorescence lifetime, which approximate to 0.680 ms, can then be obtained from the measured excitation and fluorescence waveforms by non-linear least square curve fitting based on the principle of phase-shift measurement of fluorescence lifetime. Data processing methods considering respectively the high order harmonics in the modulation and multi-exponential decay of the fluorescence were discussed. A method of utilizing Fourier series expandedness to amendatory the result was put forward. Accordingly, the applicability for phase-shift method was expanded as well as a more exact result was acquired.
authors.affiliation: Institute of Optoelectronics and Technology, Beijing Jiaotong University, Key Laboratory of Luminescence and Optical Information Ministry of Education, Beijing 100044, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Feng
authors.forename: Shi-hua
authors.initials: SH
authors.lastname: Huang