用于频域光学相干层析成像的深度分辨色散补偿方法

提出一种深度分辨的色散补偿方法,用于增强频域光学相干层析成像的纵向分辨率。将频域光学相干层析成像采集的干涉谱信号傅里叶变换到空域,获取对应不同深度的干涉谱条纹相位,通过对其进行调整实现对被测样品不同深度处的色散的精确补偿。避免传统方法中采用统一色散系数进行色散补偿所带来的过补偿与欠补偿误差,可以有效消除色散引起的频域光学相干层析成像系统点扩展函数的展宽和扭曲。模拟和实验结果表明,基于深度分辨的色散补偿方法在样品的全深度探测范围内可以达到较佳的补偿效果,可有效提高光学相干层析成像系统的纵向分辨率。

Optical Coherence Tomography Based on Depth Resolved Dispersion Compensation

A new method of depth resolved dispersion compensation to enhance the axial resolution in Fourier-domain optical coherence tomography is proposed. In this method dispersion of light over whole imaging depth range is compensated accurately with depth-resolved dispersion coefficients which are obtained by windowed Fourier transform of spectral interferogram. The proposed method can simultaneously compensate broadening and distortion of point spread function in different imaging depth compared to traditional dispersion compensation method where over and lack of dispersion compensation arise because a uniform dispersion coefficient is used. Results of computer simulation and experiments indicate that the proposed method can make a good dispersion compensation and improve axial resolution through the whole imaging depth of Fourier domain optical coherence tomography.