You see using the your eye. Light is focused onto the layer of cells of the back of your eye known as the retina, light receptors on retina then receive and transmit that information to the brain. The brain, conveys and translate all that into an image.
When you look at something...
- The image must be reduced in size so that it can fit on the retina
The scattered light must come together and must be focused onto retina to form a image
Since the surface of the retina is curved, the image must be curved to match the curvature of retina
Problems that your eye may encounter
Sometimes the eye cannot focus the image onto the retina sharply and precisely due to various reasons. For example, the surface of the lens or cornea …show more content…
Nowadays, there are around 6 out of 10 people wear glasses or contact lenses in developed countries, and roughly there are 71 million people wear contact lenses. This helps to improve their daily lives greatly, since there are many tasks that require good vision. And contact lenses enable people to have clear vision without going through all the problems that eyeglasses bring.
Contact lenses have two main advantages over glasses, sports and cosmetic. The reason that it helps in sports is because glasses easily fall down when doing vigorous sports like running. With contact lenses people do not need to worry about this problem, not to mention the hassles brought by sliding glasses due to sweating. Contact lenses also enable the fogging of glasses caused by entering a warm place from cold areas not to exist. Moreover, Orthokeratology can only be done with contact lenses.
Although contact lenses have many advantages, there is still some drawbacks. If people do not clean their contact lenses properly, or they wear the contact lenses for too long, or they do not replace the contact lenses regularly as told by the doctor, then they will have a high chance of getting eye diseases, such as Keratitis, or even eye