A STUDY OF UNDERWATER REMOTE-SENSING USING POLARIZATION AND FLUORESCENCE

本研究的目的是评估成像激光雷达利用偏振和荧光技术观测海洋生物鱼群的能力，并加强相关的基础数据。利用激光雷达方程，估计了物体、环境和设备的光学参数对检测信噪比S/N的影响，VBF（体积后向散射函数）、衰减系数和FOV（视场）是需要进行足够检查的事项。研制的原型系统通过对入射偏振激光束周围后向散射图像的CCD图像进行处理，得到了米勒矩阵元素。观察了样品的大小、形状、光学活性等特征对强度和三叶草类型格局的影响，并成功地定量了浮游生物和乳汁等测量样品中的基质元素。利用蒙特卡罗方法模拟了多个散射过程，并与实验结果进行了比较。通过这种模拟，可以估计粒子的散射特性，明确应用于模拟的散射模型的极限，也可以更高的精度假设视场的影响。此外，在研究过程中，测量了鱼体激光诱导荧光的基本数据，并进行了成像激光雷达的初步观测实验

The purpose of this research was to evaluate the ability of an imaging lidar which observed shoals of marine livings using techniques of polarization and fluorescent and to enhance related basic data.By using the lidar equation, the influences exerted on S/N (Signal to noise ratio) of the detection were estimated, which were optical parameters of objects, the environment, and a device, VBF (Volume backscattering function), the attenuation coefficient, and FOV (Field of view) were matters for which enough examinations were still needed.The developed prototype system obtained experimentally Mueller matrix elements by processing a CCD picture of the backscattering image around the incident polarized laser beam. The characteristic of the sample (size, shape, and optical activity, etc.) influenced on the intensity and the clover type pattern were observed and were successfully quantified the Matrix elements in measuring samples such as the plankton and milk.The multiple scattering processes were simulated by the Monte-Carlo method, and the result was compared with experimental result. By this simulation it became possible to estimate the scattered characteristic of particles, to clarify the limit of the scattering model applied to the simulation, and also to presume the effect of FOV with higher accuracy.In addition, during the research, a basic data concerning the laser induced fluorescence of the fish body was measured and the preliminary observation of an imaging lidar was experimented