What is Hyperopia?
People with hyperopia or hypermetropia are said to have farsightedness or longsightedness. What happens here is that light rays do not focus on the surface of the retina but behind it. These results in images being blurry when perceived. Blurred vision is caused by myopia as well, but the reasons differ in both cases. In hyperopia image formation of nearby objects appears out of focus but objects far away can be seen clearly.
Did you know that some children are born with this condition? This is because their eyeballs are short and therefore the image is not formed in front of the retina. They outgrow this defect after a while and the eyeball lengthens with normal growth. Another cause for hyperopia to occur is that the focusing power of the crystalline lens increases and this causes the image to be formed behind the retina.
If you already know about myopia then you would have realized that hyperopia and myopia are opposites of each other.
Treatment for Hypermetropia:
It is important to remember that Hyperopia is an eye defect and not an eye disease. Therefore, it can be corrected. Since the image is formed behind the retina, correcting this problem can counter the effects produced due to hyperopia.
The image above shows how the effects of hyperopia can be countered theoretically. It can be done in the following ways.
- By using corrective eyeglasses: Depending on by how much the focal length has been altered due to the effects of hyperopia, powered convex lenses can correct this problem. It is also the safest option with a minor inconveniences
- By using contact lenses: Using this has the same effect as that of using eyeglasses but presents a more convenient and comfortable option. Using contact lenses isn’t safe for everyone, however.
- Refractive surgery: Since the refractive power of the eye is affected by hyperopia, altering this through surgery is another way to counter the defects. An example of refractive surgery is Lasik surgery which is quite common.
People with farsightedness have powers with a positive sign. For example +1.50 or +2.50 as their corrective powers. This signifies that the lens used is convex in nature. These people mostly use their eyeglasses or contacts only when they are reading or using the laptop and another close-up work.
Stay tuned with byju’s to learn more about the Human Eye and all its functions through animated video modules.
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