在弱物体近似下分析了ＯＣＴ系统横向二维图像形成过程，研究表明，对于高斯像面图像传输，ＯＣＴ系统相当于一复振幅线性空间不变系统，所得二维相干传递函数表明系统具有低通特性，选用较小光纤－透镜间隔，对成像性能影响不大，减少所用透镜焦距、增大光瞳孔径，均有助于增宽系统带宽，改善成像性能． The analysis of the horizontal two-dimensional image formation of OCT system is made under the condition of weak object approximation. The results show that the OCT system is equivalent to a complex amplitude linear space invariant system for Gaussian image plane image transmission. The obtained two-dimensional coherent transfer function shows that the system has low-pass Characteristics, the use of smaller fiber - lens spacing, the imaging performance has little effect, reducing the lens focal length used to increase the pupil diameter, are helpful to broaden the system bandwidth and improve imaging performance.