建立了基于傅里叶域锁模(FDML)扫频光相干层析(OCT)系统的数值模型, 通过对FDML光源中的组件进行建模, 利用分步傅里叶法求解非线性薛定谔方程, 研究了滤波器带宽对光源强度噪声与相位噪声的影响。在此基础上对OCT成像过程中的信号进行了数值仿真, 研究了光源噪声和成像系统中的色散失配对点扩散函数及其滚降特性的影响, 获得了扫频光源中元件特性与OCT系统性能的直接关系。

In this paper, a numerical model of a swept-source optical coherence tomography (OCT) system based on Fourier-domain mode-locked (FDML) laser was described. In this method, all the optical components of the laser were modeled separately and split-step Fourier method was used to solve the nonlinear Schrdinger equation. The influences of the filter bandwidth on the relative intensity noise and phase noise were studied. Based on these results, the signal in OCT system was simulated to investigate the connection between noise, dispersion mismatch and roll-off of the point spread functions(PSF). As a result, a direct understanding for the relationship between the components of the swept-source and the performance of the OCT system was obtained.