As a high-resolution optical imaging technology, Optical Coherence Tomography (OCT) has been widely used in the diagnosis and treatment of cardiovascular diseases. It has played an important role in the detection and identification of atherosclerotic plaques and has significant advantages. In this paper, we realized to extract the optical characteristic parameters of the target sample based on the OCT data by establishing optical transmission models conforming to the OCT principle. The optical phantoms and coronary artery of domestic pig were used as research samples to study the difference between the optical properties of the cardiovascular tissues. It can provide a basic method for further study of optical characteristic parameters of atherosclerotic plaques, and also lay a foundation for realizing the quantitative evaluation of atherosclerotic plaques with multiple optical characteristic parameters in the future.

解析梯度折射率(GRIN)光纤探针的光学特征参数，用于光学相干层析技术(OCT)探头超小型化的研究。在概述由单模光纤、无芯光纤和GRIN光纤镜头构成的GRIN光纤探针模型的基础上，定义GRIN光纤探针的工作距离和聚焦光斑尺寸等光学特征参数，并用高斯光束复参数矩阵变换的方法推导探针光学特征参数的数学表达式，提出了探针光学特征参数的验证方法。结果显示，当无芯光纤和GRIN光纤镜头长度分别为0.48 mm和0.17 mm时，理论计算的工作距离和聚焦光斑尺寸分别为1.05 mm和28.2 μm；实验测得的工作距离和聚焦光斑尺寸分别为1.0 mm和28 μm。理论计算与实测结果吻合，验证了GRIN光纤探针光学特征参数及其解析方法的有效性。