研制了一套探头末端直径为1 mm的血管内扫频光学相干层析成像（IV-OCT）系统。为了确保探头内格林透镜的中轴线与安装在微型电机轴上的直角棱镜的中轴线对准，制作了尺寸匹配的塑料套管；将格林透镜插入塑料套管后与微型电机一同安装于聚四氟乙烯（PTFE）管中，制成了末端直径为1 mm的探头。对光源自带的k-clock信号进行硬件滤波以去除其中的直流分量和谐波分量，提高了系统分辨率。对等波数域间隔重采样后的干涉光谱数据进行加窗、快速傅里叶变换(FFT)、取对数、背景去除后，将得到的多个轴向扫描(A-scan)数据进行坐标变换、重建，从而得到圆环显示的样品图像。实测系统纵向分辨率为11.8 μm，横向分辨率为24 μm，成像帧速为30 frame/s。利用研制的IV-OCT系统，实现了管状白胶带、小葱葱管、藕、离体鸭血管样品的OCT成像。

An intravascular optical coherence tomographic (IV-OCT) system is developed, in which the diameter at the tip of the catheter probe is only 1 mm. In order to ensure the central axes of the Grin lens and the right angle prism attached to the micro motor shaft are aligned, a size-matching plastic sheath is designed to wrap the Grin lens. Then the Grin lens with the plastic sheath and the right angle prism are installed into a polytetrafluoroethylene (PTFE) sheath to assemble the probe, which has 1 mm diameter at the tip. A hardware filter is applied to removing the direct current component and the harmonic component in the k-clock signal generated by the swept laser source, and the resolution of the system is improved. The filtered k-clock signal is used as a trigger signal to resample the interference signal in the uniform k-space. Windowing, Fast Fourier Transform (FFT), logarithm, and background removal are applied to the resampled signal to get the A-scan data. At last, the coordinate transformation is applied to the A-scan data to reconstruct the circular display sample image. The axial resolution and the lateral resolution are 11.8 μm and 24 μm, respectively in actual measurement. The system imaging frame rate is 30 frame/s. With the proposed IV-OCT system, images of tubular white tape sample, shallot leaf, lotus root, and in vitro duck blood vessels are obtained.