A new method of Monte Carlo simulation is developed to simulate the photon migration path in a scattering medium after an ultrashort-pulse laser beam comes into the medium. The most probable trajectory of photons at an instant can be obtained with this method. How the photon migration paths are affected by the optical parameters of the scattering medium is analyzed. It is also concluded that the absorption coefficient has no effect on the most probable trajectory of photons.

The imaging technology of stimulated emission depletion (STED) utilizes the nonlinearity relationship between the fluorescence saturation and the excited state stimulated depletion. It implements three-dimensional (3D) imaging and breaks the diffraction barrier of far-field light microscopy by restricting fluorescent molecules at a sub-diffraction spot. In order to improve the resolution which attained by this technology, the computer simulation on temporal behavior of population probabilities of the sample was made in this paper, and the optimized parameters such as intensity, duration and delay time of the STED pulse were given.

In single-particle tracking (SPT), fluorescence video microscopy is used to record the motion images of single particle or single molecule. Here, by using a total-internal-reflection microscope equipped with an argon ion laser and a charge-coupled device (CCD) camera with high-speed and high-sensitivity, video images of single nanobeads in solutions were obtained. From the trajectories, the diffusion coefficient of individual nanobead was determined by the mean square displacements as a function of time. The sizes of nanobeads were calculated by Stokes-Einstein equation, and the results were compared with the actual values.

A constrained high-order statistical algorithm is proposed to blindly deconvolute the measured spectral data and estimate the response function of the instruments simultaneously. In this algorithm, no prior-knowledge is necessary except a proper length of the unit-impulse response. This length can be easily set to be the width of the narrowest spectral line by observing the measured data. The feasibility of this method has been demonstrated experimentally by the measured Raman and absorption spectral data.

根据博里叶光学传输表达式,利用数值计算方法,首次给出了小于衍用极限的小孔处于夫朗和菲区时,理想光束和像差光束经过它之后的波面相位变化.

利用横向剪切干涉法和轴向全息干涉法分别测量了处于大气压下和真空状态中的空间滤波器的窗口畸变;滤波器处于真空状态下,中心区域畸变量小于0.1λ,边缘最大的畸变量为0.41λ;分别利用全息复元法和数值计算法给出了这种畸变光束的焦体分布;计算了该窗口在不同功率密度的激光作用下的非线性畸变,它是高功率激光系统中的主要象差来源.

本文通过对宽频带及窄频带激光束的传输进行的模拟计算与实验,比较了相干光与部分相干光的传输性质。作者认为宽频带激光束的传输技术是克服当前用于激光核聚变的固体高功率钕玻璃激光器亮度的受限的重要新途径。