Ultrahigh-resolution optical coherence tomography with monochromatic and chromatic aberration correction.
Ultrahigh-resolution optical coherence tomography with monochromatic and chromatic aberration correction.
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DOI：
10.1364/oe.16.008126
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发表时间：
2008-05
期刊：
影响因子：
3.8
通讯作者：
R. Zawadzki;B. Cense;Yan Zhang;Stacey S. Choi;Donald T. Miller;J. Werner
中科院分区：
文献类型：
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作者：
R. Zawadzki;B. Cense;Yan Zhang;Stacey S. Choi;Donald T. Miller;J. Werner
我们开发了一种改进的自适应光学-光学相干断层扫描（AO-OCT）系统，并评估了其在正常和病理视网膜的活体成像性能。该仪器在视网膜上提供前所未有的图像质量，各向同性3D分辨率为3.5 x 3.5 x 3.5微米（3）。仪器分辨率的关键是一个定制的消色差透镜，用于校正眼睛的纵向色差和超宽带光源（Δ λ =112 nm λ（0）=约836 nm）。眼睛的横向色差的建模和预测是足够小的成像条件下考虑。消色差透镜被策略性地放置在AO-OCT样品臂的光输入处。该位置简化了消色差透镜的使用，并且允许直接实施到现有OCT系统中。横向分辨率的实现与AO系统级联两个波前校正器，一个大行程双压电晶片变形镜（DM）和微机电系统（MEMS）DM与大量的致动器。这种组合在检查的眼睛中产生衍射限制成像。宽带光源的另一个好处是减少轴向尺寸上的散斑尺寸。此外，通过对同一近端视网膜片的多次B扫描求平均值来降低散斑对比度。发现改进的微米级3D分辨率与减小的散斑尺寸和对比度的组合显著提高了视网膜中微观结构的可见性。
We have developed an improved adaptive optics - optical coherence tomography (AO-OCT) system and evaluated its performance for in vivo imaging of normal and pathologic retina. The instrument provides unprecedented image quality at the retina with isotropic 3D resolution of 3.5 x 3.5 x 3.5 microm(3). Critical to the instrument's resolution is a customized achromatizing lens that corrects for the eye's longitudinal chromatic aberration and an ultra broadband light source (Delta lambda=112 nm lambda(0)= approximately 836 nm). The eye's transverse chromatic aberrations is modeled and predicted to be sufficiently small for the imaging conditions considered. The achromatizing lens was strategically placed at the light input of the AO-OCT sample arm. This location simplifies use of the achromatizing lens and allows straightforward implementation into existing OCT systems. Lateral resolution was achieved with an AO system that cascades two wavefront correctors, a large stroke bimorph deformable mirror (DM) and a micro-electromechanical system (MEMS) DM with a high number of actuators. This combination yielded diffraction-limited imaging in the eyes examined. An added benefit of the broadband light source is the reduction of speckle size in the axial dimension. Additionally, speckle contrast was reduced by averaging multiple B-scans of the same proximal patch of retina. The combination of improved micron-scale 3D resolution, and reduced speckle size and contrast were found to significantly improve visibility of microscopic structures in the retina.