Multi-angle, refraction corrected robotically aligned optical coherence tomography for the anterior eye

Anterior segment OCT aids in clinical assessment of anterior eye diseases and corneal structure in the clinic, but it is affected by speckle and angularly dependent backscattering intensity. Multi-angle optical coherence tomography (OCT) of the anterior segment can counteract these two angularly dependent phenomena to produce clearer visualizations with reduced speckle. We present a robotic multi-angle OCT system equipped with robotic pupil alignment capabilities and in-line high-resolution monochrome photography. The OCT sample arm, high-resolution camera, and three pupil-tracking cameras sit within a robot-mounted scan head at a 70 mm working distance. We rotate the system incrementally around the cornea to capture varying views of the eye, imaging the entire anterior segment with the 250 kHz swept-source OCT (~23 µm resolution) and the monochrome camera (>25 lp/mm). We acquire multi-angle B-scans of an anterior eye phantom (-20°–20°), perform dual-surface refraction correction, register the images, and merge them to yield clearer visualization of the cornea.