A system for imaging a retina includes an optical relay system having a first lens for positioning proximate to an eye, a light source positioned to illuminate the eye, an image sensor positioned to capture a retinal image of the retina through the first lens, an aperture disposed between the image sensor and the first lens along an optical path extending from the image sensor through the first lens, and a processing apparatus. The aperture surrounds the optical path and is adapted to block off-axis reflections from the eye.