受激发射损耗荧光显微镜利用荧光饱和和激发态荧光受激损耗的非线性关系,通过限制损耗区域,可突破远场光学显微术的衍射极限分辨力并实现三维成像。基于对粒子速率方程组的修正,建立了描述荧光团各能级粒子数概率时间特性的模型,并定义了时间平均损耗效率判据。采用高斯函数模拟两束入射激光脉冲通过对模型的数值计算,模拟了激发脉冲的SIED激光脉冲的光强、脉冲宽度以及两束光的延迟时间等参量与损耗效率之间的关系,并获得了各参量的最佳值,优化了损耗效率,为提高系统分辨力提供了有效的途径。

The imaging technology of stimulated emission depletion (STED) fluorescence microscopy utilizes the nonlinear relationship between the fluorescence saturation and the excited state stimulated depletion. It implements 3D imaging and breaks the diffraction barrier of the far-field light microscopy by restricting depetion zone at a sub-diffraction spot. A model on the revision of the particle velocity equations was found to depict the temporal characteristics of the energy level population probability of fluorescent prob, and the oriterion called time verage depletion efficiency was defined. Gaussian function was used to simulate the two incident laser pulse, and the relationship between the depletion efficiency and the parameters, such as intensity, duration, delay time of both laser pulses, was obtained repsectively by numerical simulation, and the optimal value of these parameters was gained to improve the depletion efficiency is obtained. It is an effective approach to advance the system resolution.