适合于内窥成像的共路型光学相干层析成像系统

Common Path Optical Coherence Tomographic System Suitable for Endoscopic Imaging

提出了一种采用光纤型迈克耳孙干涉仪进行光程补偿的菲佐型光学相干层析成像(OCT)系统。该系统的传感探头为共路干涉结构,以解决现有内窥光学相干层析成像系统中存在的探头运动导致图像失真、以及更换使用不同探头时需进行色散和偏振态调节等问题。光程补偿和振动干扰实验结果表明,光程补偿方法正确可行,系统对环境干扰不敏感。利用研制的系统对反射镜和近红外卡进行了成像实验,验证了系统的有效性。提出的方法非常适合于内窥成像,并给出了把系统扩展为内窥光学相干层析成像系统的具体实现过程。

A Fizeau interferometer based optical coherence tomographic （OCT） system using a fibre-based Michelson interferometer to compensate the optical path difference between the reference and sample light in the Fizeau interferometer is presented. The sensing probe of the system is a common path interferometer which can solve the problems existing in current endoscopic OCT systems, such as image distortion due to probe motion, and dispersion and polarization matching which are required when various probes are used. Experiments of path length compensation and vibration are conducted and the results demonstrate that this path length compensation method is feasible and the system can avoid environmental turbulences. Mirror and infrared card are imaged to demonstrate the performance of the proposed OCT system. This imaging approach is thus very suitable for endoscopic imaging, and the detailed method of expanding the OCT system for endoscopic OCT imaging is also presented.