移位复用复频域光学相干层析成像研究

Characteristics of Shift-Multiplexing Complex Spectral Domain Optical Coherence Tomography

基于复频域光学相干层析成像(CSD-OCT)系统在参考镜虚像位置附近成像分辨率高的特点,采用移位复用复频域光学相干层析成像方法,通过将参考镜虚像位置依次移到样品特定待测深度,获取整个样品感兴趣深度区域的高质量成像。进一步结合横向扫描,对多层堆叠的盖玻片样品进行了移位复用层析成像实验,结果表明,将参考镜虚像位置移到样品内部指定探测位置附近进行去镜像层析成像,可以获得该区域更加清晰的层析成像结果。该方法可以获得更深的有效探测深度,灵活地实现样品指定深度的有效成像探测,也充分利用了光学相干层析成像系统的带宽。

The shift-multiplexing complex spectral domain optical coherence tomography （CSD-OCT） is presented according to the occurrence of high-resolution tomographic image near the virtual image of reference mirror. The method of shift-multiplexing CSD-OCT is experimentally demonstrated by using ~/2 phase-shifting algorithm to remove complex conjugate image and by shifting detection position to improve the quality of tomographic image, detection depth and bandwidth utilization. The tomographic imaging for a target sample of five-layer cover slips is performed in different depth regions with this method. The tomographic imaging of the sample made of eight-layer cover slips is further carried out combining with lateral scanning. The tomographic images of the target object are clear and legible. The results show that the higher quality tomographic image of a target sample within its desired depth can be achieved by moving the virtual image of reference mirror to the specified depth of the sample. The CSD- OCT system with shifting detection can effectively extend the detection range inside sample, perform tomographic imaging at the specified location and make full use of optical coherence tomography system＇s bandwidth. The tomographic image of an object in its depth-target area can be improved.