Light behaves like a physical probe that pokes and prods the inside of a living human eye to check for disease.

Retinal tissue moves by just a few nanometers when it is hit with specific light pulses. Doctors previously had to rely on visual scans to find damage, but these scans often miss the subtle stiffening that signals early stage blindness. This new method uses the eye’s own response to light as a mechanical hammer to measure elasticity without ever touching the eyeball. Hardware sensitive enough to detect these tiny vibrations provides a high resolution map of where the retina is softening or hardening. This technology means people could get a diagnosis for glaucoma or macular degeneration years before they actually lose their vision.