Spatially resolved reflectance close to source has received a great deal of attention recently. This research is considered to develop a new noninvasive technique for measuring the optical properties of biological media. Using Monte Carlo simulations, we investigated the influence of third-order parameter on diffuse reflectance and found that the reflectance decreased with an increase of at a short source-detector separation of approximately 0.7-2 transport mean free paths. We show that the effects of two parameters, and secondorder parameter, on the reflectance are contrary. As a result the influence of the second-order parameter on the reflectance is irregular when the condition is not satisfied.

Isolation of a new structured acousto optic switch based on an integTatcd optical polarization independent quasi collinear acousto optic tunaSIe filter is studied in detail. The factors that influence the isolation of the optical switch are analysed, the expressions of the isolation are educed, and the isolation of the dev/ce is measured in experiment. It is found that the isolation mainly depends on the TE/TM mode intensity ratio, the mode splitter extinction rate, and the conversion efficiency.

Influences of the scattering phase functions on spatially resolved diffuse reflectance from a homogenous semi-infinite medium close to source are studied with Monte Carlo simulation. It is shown that the influences of optical parameters higher than the second order on the diffuse reflectance are quite weak in the region from 0.3 to several transport mean free pathes when Henyey-Greenstein phase function or a combined phase function of two parameters are used. But this influence may be substantial if the double Henyey-Greenstein function is used to describe the scattering property of tissue.

在集成声光可调谐滤波器（AOTF）工作时，由于环境温度变化以及自身声表面波吸收使器件的温度发生变化，导致滤出波的中心波长发生漂移。在理论分析的基础上，对声光可调谐滤波器的温度特性进行了实验研究，并在此基础上提出一种新的解决方案：用动态控制射频信号来实现声光可调谐滤波器的稳频输出，并用该方案实现了中心波长的漂移控制在0.08nm以内，满足了波分复用（WDM）通信系统的应用要求。

设计了一种以新型两级集成光学声光可调谐滤波器（IAOTF）为调谐元件的环形腔单偏振输出可调谐掺铒光纤激光器，它具有结构简单、调谐方便、调谐速度快和调谐范围大的优点。在对该集成光学声光可调谐滤波器滤波特性进行分析的基础上，在忽略放大的自发辐射（ASE）和激发态吸收情况下，对该激光器的特性参量如线宽、输出功率、斜率效率、阈值抽运功率等进行了分析。当抽运功率为100mW，射频为175MHz时，激光器输出中心波长为1550nm，最大输出功率约6.34mw，斜率效率为7.19%，半峰全宽（FWHM）为0.1nm。当声波频率每改变0.1MHz时，激光器输出中心波长改变约为0.88nm，由于集成光学声光可调谐滤波器的滤波范围很大（当声波频率变化20MHz时，滤波范围为180nm），所以激光器的调谐范围仅取决于掺铒光纤的增益带宽。