Non-mydriatic ultra-widefield diffraction-limited retinal imaging

We demonstrate a new non-mydriatic ultra-widefield optical coherence tomography retinal imaging system, designed with custom optics to improve the imaging field of view, lateral resolution, and patient comfort. The key motivation is to address the challenge with conventional systems which require pupillary dilation, adding time, expense, discomfort, and medical risk to the examination of the retina. Our system provides an ultra-wide 100° field of view (visual angle measured from the pupil plane) and maintains a lateral resolution of 20 µm throughout the field of view. It also allows a generous working distance of 16 mm, 2-3 times longer than existing ultra-widefield OCT imaging systems. This advanced system was able to avoid iris vignetting artifacts without pharmacological dilation and ensure diffraction-limited ultra-widefield imaging. This enables comprehensive evaluation of retina diseases, especially those affecting the peripheral regions.