线聚焦谱域光学相干层析成像的分段色散补偿像质优化方法

Image quality optimization of line-focused spectral domain optical coherence tomography with subsection dispersion compensation

本研究中搭建了一套用于生物样品成像的线聚焦谱域光学相干层析(LF-SD-OCT)系统,针对系统误差引起的轴向展宽和灵敏度衰减问题,提出了一种分段色散补偿的方法,对成像深度内的二阶和三阶色散相位进行了补偿,并通过平面镜和透明胶带样品成像实验来验证该方法的有效性和可靠性。通过本文提出的分段色散补偿方法和其他成熟方法的联合应用,系统在获得57.2 kHz的等效A-scan速率的同时,轴向分辨率提升至6.76μm,对胶带样品2 mm深度范围内及水果样品0.3 mm深度范围内进行了较清晰成像。实验结果表明,该方法可以在兼顾处理效率的同时提高全深度轴向分辨率和灵敏度,未来有望广泛实现线聚焦谱域光学相干层析的生物医学成像应用。

In this study,a line-focused spectral domain optical coherence tomography(LF-SD-OCT)system for imaging biological samples was built,and a data processing algorithm to improve the imaging quality was proposed to solve most of the problems of axial broadening and sensitivity attenuation caused by systematic errors.In particular,a segmented dispersion compensation method is proposed to compensate the second-and third-order dispersion phases in the imaging depth.The effectiveness and reliability of this method are verified by the imaging experiments of plane mirrors and scotch tape samples.Finally,it is proved that this method can improve the full-depth axial resolution and sensitivity without affecting the image processing speed.The final system can achieve the axial resolution of 6.76μm and an equivalent A-scan rate of 57.2 kHz,and clearly image the tape sample within 2 mm depth and the apple sample within 0.3 mm depth.In the future,it is expected to widely realize the biological imaging applications of line-focused spectral domain optical coherence tomography.