Narawane Amit, Ortiz Pablo, Draelos Mark, McNabb Ryan P, Kuo Anthony N, Izatt Joseph A
Opt Lett. 2025 Mar 15;50(6):1969-1972. doi: 10.1364/OL.547035.
Optical coherence tomography (OCT) systems utilize 2D scanning methods to acquire reflectance-based volumetric images of samples, such as the human retina, with micrometer-scale depth resolution. A common method for performing this scanning at high speeds is to use a pair of sequential, single-axis galvanometer scanners. An undesired effect of using separated scanners is the variation in the beam position at the pupil plane, a phenomenon known as beam wander or pupil wobble. This can lead to loss of signal and vignetting artifacts in the resulting images. To overcome these limitations, we propose a method to deterministically analyze the pupil wobble in a given retinal OCT system and to correct for the displacement using pupil tracking OCT with a 2D scanning mirror placed anti-conjugate to the pupil plane. We demonstrate that we can model the pattern of pupil wobble present in any OCT system both theoretically and empirically and then use a pupil tracking system to correct for the displacement of the beam to acquire OCT images without the imposed artifacts.
光学相干断层扫描（OCT）系统利用二维扫描方法，以微米级的深度分辨率获取基于反射率的样本体积图像，如人类视网膜。在高速执行这种扫描的一种常用方法是使用一对顺序排列的单轴振镜扫描仪。使用分离扫描仪的一个不良影响是光束在光瞳平面处位置的变化，这种现象称为光束漂移或光瞳摆动。这可能导致所得图像中的信号丢失和渐晕伪影。为了克服这些限制，我们提出了一种方法，用于确定性地分析给定视网膜OCT系统中的光瞳摆动，并使用与光瞳平面反共轭放置的二维扫描镜的瞳孔跟踪OCT来校正位移。我们证明，我们可以在理论上和经验上对任何OCT系统中存在的光瞳摆动模式进行建模，然后使用瞳孔跟踪系统校正光束的位移，以获取没有伪影的OCT图像。
