Human Eye
Summary
The eye works something like a camera. Light passes through the camera’s curved lens, which focuses the image. The image forms behind the lens, and is recorded on the film, or the digital sensor. In a similar way, light passes through the lens of a human eye. It firsts passes through the cornea – which bends the light passing through the eye slightly, so the resulting image will be focused. The light then enters the eye through the opening in the eye, called the pupil, and passes through the iris, sheets of smooth muscle that expand and contract to regulate how much light enters the inside of the eye. In bright light, the iris contracts around the pupil to keep out too much light. When it is dark, the iris expands to let in as much light as possible.
Keywords: retinitis pigmentosis, eyesight, blindness
