Seven things you are doing that will strain your eyes
There is no running away from technology. Computers, smart phones are no longer a luxury, they are a must-have for everyone, from students, corporate professionals and businessmen.
One must never forget the fact that 80 percent of the things taught to children at school are visual in nature.
A brief explanation of the eye may be of assistance in understanding the procedure. The cornea is a clear tissue located on the front of the eye. The cornea, in combination with the natural lens of the eye, focuses the incoming light onto the retina in the back of the eye. Refractive errors (myopia, hyperopia, and astigmatism) usually result from a disparity in the shape of the cornea in relationship to the length of the eye.
Emmetropia is the condition of the normal eye when parallel rays are focused exactly on the retina and vision is perfect.
When light doesn't focus directly on the retina, the eye has a refractive error and will cause blurred vision. The appropriate corrective lenses are used in front of eye, to focus incoming rays on the retina, which will give clear vision.
1. Myopia or Nearsightedness:
Myopia is caused either by an abnormally long eye or by a steep curvature to the cornea. Light entering the eye does not focus on the retina, but instead focuses the image to a point in front of the retina. The result of myopia is that distant objects appear blurry, while objects near object are very clear.
Concave glass is used to focus them on retina.
The Excimer laser can flatten the corneal curvature allowing objects to be in focus in the distance.
2. Hyperopia or Hypermetropia or Farsightedness:
Farsightedness is caused by an abnormally short eye or by an excessively flat cornea. Light entering the eye focuses the image to a point behind the retina. The result of hyperopia is that both near objects and fare are blur.
Convex glass is used to focus them on retina.
The Excimer laser can increase the corneal curvature(steepening) allowing objects to be in focus in the distance.
In the normal eye, the cornea is curved the same in the horizontal and vertical directions, like a baseball. When light rays hit the cornea, they focus at a single point.
In astigmatism, the curve of the cornea is not the same in the horizontal and vertical directions. The cornea looks like a football, with a steep curve on one side and a flat surface on the other. As a result, light rays entering the cornea do not focus at a single point, causing distorted vision.
Most people with myopia or hyperopia have some degree of astigmatism.
The Excimer laser can adjust the corneal curvatures allowing objects to be in focus.
Normally, when viewing a near object, the shape of the natural crystalline lens is altered. This change in the lens allows us to focus on the object closer to eye. As we age, the natural crystalline lens of the eye may lose some of its elasticity and thereby its ability to focus on close objects. This condition, known as presbyopia, usually begins around the age of 40 and will keep on progressing till you become 60 years of age.
Generally, reading glasses are prescribed to correct Presbyopia.
Supracor or Intracor procedure can help you reading without glasses.