采用频域光延迟线的光学相干层析成像

频域光延迟线是一种光学扫描结构,其基本组成是一个衍射光栅、一个透镜和一个扫描镜.把频域光延迟线应用到光学相干层析成像系统中,可以使参考臂扫描速率至少达到数m/s以上,从而实现视频速率的图像获取.从几何光学的角度分析了频域光延迟线的工作原理,分析结果表明在扫描角很小的情况下,入射光的光程或相位变化频率与扫描角频率有较好的线性关系.基于这一结构的光学相干层析成像的结果证明可以避免活体生物组织位移引入的图像模糊.另外,还提出了一种基于微执行器的新扫描装置.

An optical coherence tomography system using frequency-domain optical delay line

The frequency-domain optical delay line (FD-ODL) is a kind of optical scanning technology, which consists of a diffraction grating, a lens, and a scanning mirror. When employing FD-ODL in optical coherence tomography (OCT) system, the reference scanning speed at meter-per-second can be achieved to support image acquisition at video rate. An analysis about the principle of the FD-ODL is made at the point of geometry optics. The results show that the frequency of the optic length or phase variation is almost linear to the scanning angular frequency as the scan angle is very small. The image of an OCT system based on this structure proves that it can avoid blur induced by the displacement of the living tissue. In addition, a new scanning device is also proposed.