How Light Interacts With Vision

- Sep 04, 2019-

The human eye is a magnificently sophisticated receiver of visible light, the narrow band of light that we’re able to detect in the electromagnetic spectrum. The lens at the front of your eye serves to focus incoming rays of light toward the millions of specialized cells at the back of the eye, which are responsible for collecting and transmitting information to the brain via a series of biochemical reactions. The brain does the rest of the work to organize all that incoming information into an image of what’s in front of you.

This amazing biological process evolved a safeguard to prevent damage to these sensitive light-detecting cells within the eye. The pupil at the front of the eye expands and contracts like the aperture of a camera lens to allow only certain amounts of light to pass through, thus shielding the inner mechanisms of the eye from overexposure and burn-out. In an environment with intense light, the pupil will contract to keep a majority of the light out. Likewise, in low-light environments, it will open to draw in more light. This simple process makes the human eye, and others like it in the animal kingdom, a highly specialized biological adaptation responsible for many of the amazing evolutionary leaps that have been made by our species due to the interaction of light and vision.