How the eye works.

how the eye works The eye allows us to see, judge distances and provides one of the essential sences. It gives us a great awareness of our environment and is thought to be a great peice of natural engineering. The eye consists of a few main parts, the iris, pupil, lense,vitriouse humour and retina. I will explain how each one works. Iris: This can appear different colours on the outer eye. It expands and …

…is focused to close to the lense, meaning it is too far from the retina, this can be corrected by a convex lense. Longsightedness (hyperopia) This is very much like Shortsightedness, except the image is focused too far away from the lense, making it actually behind the retina. This can be caused by the eye being too long, as is my experience, or the lense being irregular. This can be corrected by a concave lense.