subject: Understand Myopia easily so you can know your treatment [print this page] Understand Myopia easily so you can know your treatment
As we explained before, the light rays of an image are collected on the retina (the inner light sensitive layer at the back of the eye ball) in order to form an accurate image stimulating a specific number of photoreceptors as shown in the figure below.
The problem in myopia is that either the eye ball is very large (more common) or the refractory media converge the image in a very strong way. In both cases the precise accurate image needed fall in front of the retina and not on it as shown in the following figure.
Now you may think that a myopic person won't see anything because the image falls in front of the retina as shown in the above figure. But that's not true since the above figure is not complete and I meant to do it like this to be easy to understand. Below is the complete figure showing you that instead of falling on 1 point on the retina, the image falls on many points, stimulating many photoreceptors and giving a hazy blurred image. This image corresponds to the extension of the refracted light rays.
Why do they call it short sightedness?
That's because myopic people have no problem to see near objects, but they have problems in seeing far distant objects. That's because near objects emit divergent rays while far objects emit parallel rays, and the refractive collecting power of the refractive media of the eye is fixed. The following figure will make it clearer.
Check this article to understand why far objects emit parallel rays while near objects emits diverging rays.
So how can we treat such problem?
Let's think in an easy way. If the myopic person is able to see near objects better, let's make the far objects nearer to him/her. Don't miss understand me and think that if you are a myopic your only chance to see far objects is to get nearer to them. This will make no sense.
What I meant is placing a divergent lens in front of the eye (Concave lens) to make the parallel light rays coming from the far object to be diverging rays (as the near objects). If you still don't know the difference between different lenses check errors of refraction.
Of course it is not the same lens for all myopic persons, but you need to perform accurate measurements at the doctor's clinic. The lenses may be in the form of glasses or contact lenses. See the figure below to see how it will work.
welcome to Insurances.net (https://www.insurances.net)
