How eyes work

How eyes work:
The eye is an incredibly complex part of your body. But understanding how all of the parts of the eye work together to create your sense of vision can go a long way to helping you understand why taking care of those eyes is so important. Vision is a complex sense composed of many elements. The human eye, elegant in its detail and design, represents a gateway to the process we call vision. Our bodies change as we get older. So too, do our eyes. Just care and nourish them.

Know your eyes:

1. Tears: The first line of defence, they also serve as lubrication by keeping the eyes moist and nourished; they also have a corrective lens function.
2. Eyelids: Their main job is to protect your eyes from dirt, dust and harsh light.
3. Eyelashes: A protective net for your eyes.
4. Cornea: A refractive zone that guides light to reach the retina.
5. Pupil: Controls the amount of light that enters your eyes.
6. Lens: A refractive zone that also guides light into the retina.
7. Retina and Optic Nerve: A bunch of intricate wiring that carries vision signals between your brain and eyes.

When the eye is looking at distant objects, the light rays are focussed on to the retina. If it is a near vision, the focus of the lens is adjusted by the surrounding ciliary muscle. The retina changes light into electrical energy (just as a light meter does) and processes this into coded impulses to be transmitted to the brain. So, an image passing through the eye lens is transmitted from the retina to the brain via the optic nerves. There is a complex mixing of the impulses so that the right side of the brain sees everything on your left and vice versa.

Just like the camera, the image appears upside down on the retina, but the brain instantly converts it so that one sees everything the right way up. The eyes move together and send almost identical images to the brain. The brain then joins these images into a single mental picture