Is the most significant and precious part of our body. As much as 70 – 80% of what we perceive and learn is achieved through vision. Being able to see clearly is , therefore , the most important factor that influences our capacity to lead and enjoy a normal life.
Is the result of light being focused by the cornea and the crystalline lens on to the retina. If the eye's foucsing power does not correspond with it's length, the retina will not receive a clear, focused image, causing a condition called a Refractive Error or Ametropia. This condition can be categorized in to the following forms.
The images of distant objects are focused in front of the retina , and are therefore blurred on the retina.The affected person can see more clearly neer objects than distance objects. Approximately 30 % of the world's population are near sighted.
The optical system has difficulty focusing the images clearly before the light rays reach the retina. Vision in the distance is not clear, and as the object approuches closer, it becomes even more blurred.
Is the result of a general inability of the eye to focus images to a single point focus. Instead of being spherical, the cornea is more similar to the shape of an egg. The focusing problem can occur along with near – sightedness, or far – sightedness.
Is a general condition affecting everyone and usually begins around the age of 40. Although distance vision can remain good, age related changes within the eye gradually weaken a person's ability to focus clearly on close objects. This condition is often confused with far-sightedness or (hyperoia).