Doubt in myopia and Hypermetropia

  • Thread starter Puneeth423
  • Start date
  • Tags
    Doubt
In summary, if a person has nearsightedness, it means their eyeball is longer than usual and they have difficulty seeing objects far away. This is because the lens in their eye does not adjust its focal length properly. Reading books and focusing on objects closer to them can cause the lens to become "stub burn" and worsen their nearsightedness. However, exercising the eye muscles does not help with nearsightedness. Astigmatism, which is when the eyeball is asymmetrical, can only be corrected with glasses that have a cylindrical element.
  • #1
Puneeth423
51
0
Will a person suffering from nearsightedness, couldn't see objects far since his eyeball is longer than the usual? (or) Because when he reads more books daily and always focus his vision on objects nearer, lens in his eye ball becomes stub burn and doesn't adjust its focal length when he watches objects far away?
 
Physics news on Phys.org
  • #2
I think just the latter. If your eyeball changes length it should affect the focus of all of your vision, not just the far away focus.
 
  • #3
The Physics / optics is that objects at only one distance are focussed on the retina. You adjust the focal length of your lens in order to accommodate over your range and get a particular object in focus. If your eye is 'longer' than normal, even with the lens muscles totally relaxed, distant objects are still not in focus (myopia). If your eye is too short (or you are old and the muscles won't work hard enough), then the muscles cannot change the focal length of the lens to bring near objects into focus.
As far as I know, it is not possible to deal with myopia by 'exercising' the muscles because they are already relaxed when you are trying to see distant objects. Some people claim that exercising the eye muscles can help with hypermetropia though.
My eyeball is aymmetrical and I suffer from astigmatism. The only way to deal with that is with glasses that have a cylindrical element to the lens shapes. So I can just be lazy.
 

1. What is the difference between myopia and hypermetropia?

Myopia, also known as nearsightedness, is a refractive error in which distant objects appear blurry while close objects can be seen clearly. This is caused by an elongation of the eyeball or a steep curvature of the cornea, resulting in light being focused in front of the retina instead of directly on it. On the other hand, hypermetropia, also known as farsightedness, is a refractive error in which close objects appear blurry while distant objects can be seen clearly. This is caused by a shortened eyeball or a flat curvature of the cornea, resulting in light being focused behind the retina instead of directly on it.

2. How do I know if I have myopia or hypermetropia?

If you have difficulty seeing objects clearly, whether they are close or far, you may have a refractive error such as myopia or hypermetropia. It is important to get an eye exam from an optometrist or ophthalmologist to determine the exact type and degree of your refractive error. They will perform tests such as a visual acuity test and a refraction test to diagnose and determine the correct prescription for your glasses or contact lenses.

3. Can myopia and hypermetropia be treated?

Yes, both myopia and hypermetropia can be treated with corrective lenses such as glasses or contact lenses. These lenses work by changing the way light enters the eye, correcting the refractive error and allowing for clear vision. In some cases, refractive surgery such as LASIK may be recommended by an eye doctor to permanently correct myopia or hypermetropia.

4. Can myopia and hypermetropia be prevented?

While there is no guaranteed way to prevent myopia or hypermetropia, there are some steps that may help reduce the risk of developing these refractive errors. These include spending time outdoors, practicing good eye hygiene (such as taking breaks from screen time and maintaining proper lighting), and getting regular eye exams to catch any changes in vision early on.

5. Are myopia and hypermetropia hereditary?

Yes, both myopia and hypermetropia can be hereditary. If one or both parents have a refractive error, their children are more likely to develop the same or a similar refractive error. However, there are also other factors that can contribute to the development of myopia and hypermetropia, such as environmental factors and lifestyle habits, so not all cases are solely based on genetics.

Similar threads

  • Introductory Physics Homework Help
Replies
1
Views
612
Replies
5
Views
2K
  • Introductory Physics Homework Help
Replies
2
Views
3K
Replies
1
Views
1K
Replies
1
Views
2K
  • Introductory Physics Homework Help
Replies
1
Views
1K
Replies
7
Views
2K
  • Astronomy and Astrophysics
Replies
25
Views
1K
  • Introductory Physics Homework Help
Replies
3
Views
1K
  • Sci-Fi Writing and World Building
2
Replies
48
Views
4K
Back
Top