Wang Donglin, Liang Peng, Samuelson Sean, Jia Hongzhi, Ma Junshan, Xie Huikai
Engineering Research Center of Optical Instrument and System, University of Shanghai for Science and Technology, Shanghai 200093, China ; WiO Technology Ltd., Co., Wuxi 214135, Jiangsu, China.
Biomed Opt Express. 2013 Sep 6;4(10):2066-77. doi: 10.1364/BOE.4.002066. eCollection 2013.
A two-axis scanning microelectromechanical (MEMS) mirror enables an optical coherence tomography (OCT) system to perform three-dimensional endoscopic imaging due to its fast scan speed and small size. However, the radial scan from the MEMS mirror causes various distortions in OCT images, namely spherical, fan-shaped and keystone distortions. In this paper, a new method is proposed to correct all of three distortions presented in OCT systems based on two-axis MEMS scanning mirrors. The spherical distortion is corrected first by directly manipulating the original spectral interferograms in the phase domain, followed by Fourier transform and three-dimensional geometrical transformation for correcting the other two types of distortions. OCT imaging experiments on a paper with square ink printed arrays and a glass tube filled with milk have been used to validate the proposed method. Distortions in OCT images of flat or curved surfaces can all be effectively removed.
两轴扫描微机电系统（MEMS）镜因其快速扫描速度和小尺寸，使光学相干断层扫描（OCT）系统能够进行三维内窥成像。然而，MEMS镜的径向扫描会在OCT图像中引起各种畸变，即球面畸变、扇形畸变和梯形畸变。本文提出了一种基于两轴MEMS扫描镜来校正OCT系统中出现的所有这三种畸变的新方法。首先通过在相位域直接处理原始光谱干涉图来校正球面畸变，然后进行傅里叶变换和三维几何变换以校正其他两种类型的畸变。对印有方形墨水阵列的纸张和装有牛奶的玻璃管进行的OCT成像实验已用于验证所提出的方法。平面或曲面的OCT图像中的畸变都可以有效地消除。
