荧光寿命的正弦调制测量法及分析

设计并制作了光强调制度和频率可调的发光二极管驱动电路，应用这种激励源激发荧光样品Eu₂L′3·nH₂O(L′=C₄H₄O₄)，测量了激发光和Eu3+离子的5D₀—7F₂发射光的波形。实验得到的数据用按照相位法测量荧光寿命的原理用非线性最小平方曲线拟合，得到Eu3+离子激发态5D₀的寿命约为0.680 ms。讨论了光源调制中的高次谐波分量对测量结果的影响以及寿命具有一定分布的多指数衰减体系的测量和处理方式，提出应用傅里叶级数展开处理数据的修正方法，以扩大相位法测量荧光寿命的适用范围，得到更准确的荧光寿命值。

The Analysis of Sinusoidal Modulated Method Used for Measuring Fluorescence Lifetime

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.