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What is the difference between myopia and hyperopia?

What is the difference between myopia and hyperopia?

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In myopia the lens is bending the light too much even in the most relaxed state. Thus the image is produced in front of the retina. If the object comes closer the lens just adjusts a bit less than a healthy eye and the myopic subject is able to see clearly.

Why is the hyperopic eye not able to do that? If the object is far away, could the lens not just bend a bit more to elicit normal vision? So, why is the Myopic eye able to adjust its focus, but the Hyperopic not?


Short answer
Myopic eyes can still focus on nearby images as the lens needs to relax a bit more than in a normally-sighted person. However, objects far away cannot be focused, because in a complete relaxed state (for distant objects), the lens focuses the image in front of the retina. Hyperopic eyes cannot focus on nearby objects as, at a certain close distance, the lens reaches maximum accomodation (maximum roundness) and objects cannot be focused any longer.

Background
Myopia or near-sightedness is a condition of the eye where the light that comes in does not directly focus on the retina but in front of it, causing the image that one sees when looking at a distant object to be out of focus, but in focus when looking at a close object. Often the eye ball is too long, or the cornea has too much curvature (Web MD).

Hyperopia ("over-measured sight") or farsightedness, is a defect of vision caused typically by the eyeball being too short, or a lens that cannot accomodate/become round enough. It causes difficulty focusing on near objects (wikipedia).


Source:Monroe Publishing


Myopia, Hyperopia and Astigmatism Explained

The names of eye conditions can sometimes be confusing, not to mention completely baffling when it comes to understanding what each condition means. Your eye doctor may have diagnosed you with one, but what does it mean? When it comes to nearsightedness, farsightedness, and astigmatism, most people aren’t quite sure of the differences. If you’re confused about what each one does to your eyes, you are not alone. Myopia, hyperopia, astigmatism – what’s the difference?

To make the explanations simpler, here is a video that you can watch. It not only explains the differences but also gives a short demonstration of each condition. The video is very informative. Seeing the demonstration of each eye problem next to an image of perfect vision is an eye-opening experience! You may now understand what your eye actually looks like and what your condition means. Keep reading to learn even more about these conditions so you can understand what’s going on with your eyes.


What is the Difference Between Myopia and Hyperopia?

For vision to work properly, both your distance and near vision should be clear. Both myopia (nearsightedness) and hyperopia (farsightedness) are refractive conditions — they refer to how light is focused in relation to the eye. Below, learn what myopia and hyperopia mean, as well as the differences between the two.

The technical term for farsightedness is hyperopia. If you are farsighted, you can see distant objects well, but reading or looking at items close up is blurry for you. With hyperopia, the eyeball is either too short or there is not enough curvature of the lens for objects to focus properly. Light will focus at a point beyond the retina instead of in front of the retina or directly on its surface. This causes blurry vision up close.

Nearsightedness, also known as myopia, is the opposite of farsightedness. It means that with your uncorrected natural vision, you have difficulty seeing at a distance. This happens when the eyeball is too long. Because it is longer than normal, light cannot focus properly through the lens and cornea. When you view an object, the light rays that hit your eye will end up focusing at a point in front of the retina instead of focusing directly at the retina. This is why objects farther away become blurrier compared to objects up close – the focusing distance is further. Nearsightedness can also be caused by the curvature of the lens of the eye. If the lens is too curved, this will throw off your focusing point as well.

Differences Between Myopia & Hyperopia

Being farsighted or nearsighted both affect your ability to see clearly. The difference between myopia and hyperopia is whether you have difficulty seeing up close or at a distance. Hyperopia (farsightedness) makes it hard to see things that are close, and Myopia (nearsightedness) makes it difficult to see things that are far away. Both conditions can be improved with corrective lenses such as glasses or contacts as well as safe LASIK surgery.

If you have any questions about being nearsightedness or farsightedness or have other concerns about your vision, schedule an eye exam at Saland Vision in Dallas by calling 214-691-8000 or visiting website today.


What is myopia?

Myopia is the most common refractive eye problem in the world, yet many people haven&rsquot heard of it. Instead, they know it by another name &ndash nearsightedness. Myopia occurs when the light is refracted by the cornea in such a way that it falls short of the retina, landing in front of it. In most cases, myopia occurs because the eyeball has grown too long relative to its focusing power.

Patients who have myopia can usually see nearby objects, such as books and digital screens clearly without prescription lenses. However, those that appear far away, such as roads and street signs, look blurred and out of focus.


The lens and ciliary muscles help us see near and far. When you look at something far away, the ciliary muscles stretch the lens and reduce the focus to make the object clearer. When the object is closer, the ciliary muscles compress and increase the focus. When light falls on the lens, it converges on the retina to form an inverted image. Myopia is the most common refractive eye disease in the world, and people with myopia usually can clearly see nearby objects, like books and digital screens. However, objects that show in the distance look blurry. People with farsightedness can see objects in the distance clearly, while those objects close to their faces are blurred.

Myopia is caused by the refraction of the cornea, which increases the distance between the lens and the retina, allowing light to converge in front of the retina. Myopia is because the eyeball has grown too long relative to its ability to focus. In farsightedness, the eyeball is too short and the focus falls behind the retina. It forms an image behind the retina, causing light to be refracted behind the eyeball.


Signs and Symptoms of Myopia

The signs and symptoms of myopia are also easy to spot. People with myopia can see objects very well if they are up close, but objects at a distance appear blurry. This can include when you are reading, using a smartphone, tablet or computer, driving, watching television or a movie, or anything else that requires long-range vision. Other signs and symptoms of myopia include eye strain and fatigue, headaches and squinting… as well as halos around lights, and even double vision in more severe cases.

If you experience any of these signs or symptoms of myopia while wearing your glasses or contact lenses, we recommend scheduling an eye exam with your trusted eye care provider to see if a different prescription can help.


Difference Between Myopia and Hyperopia

The main difference between Myopia and Hyperopia is that Myopia is a condition of the eye in which a person cannot see the far away things also known as short-sightedness. While in the case of Hyperopia condition, a person cannot see the near objects also known as long-sightedness.

Myopia vs. Hyperopia

The common eye problems are myopia or short-sightedness and hyperopia or long sightedness. These defects are also called “refractive errors or defects”. Myopia is a condition in which one person cannot see the far away things clearly but can see near objects while in case of hyperopia one person cannot see near things and can see far objects clearly. Myopia can be corrected by a double concave lens while hyperopia can be fixed by a dual convex lens. In the case of myopia, light refract in such a way that image formed in front of the retina but in case of hyperopia image formed behind the retina of the eye. In myopia eyeball size increases while decreases in hyperopia. The focal length of the eye lens decreases in myopia while increases in hyperopia.

Comparison Chart

MyopiaHyperopia
The condition of eye defect in which one person cannot see things beyond the “far point”.The state of eye defect in which a person cannot see nearer things.
Formation of Image
The image is formed in front of the retina of the eye.The image is formed behind the retina of the eye.
Causes
Increased axial length, Degeneration of choroid, Degeneration of retina and vitreous.A decreased axial length of the eye and lower refractive index.
Size of Eyeball
IncreasesDecreases
Focal Length
The focal length of the eye lens is decreased.The focal length of the eye lens is increased.
Corrected by
Using a double concave lens, laser, and surgical treatments.Using a dual convex lens, laser, and surgical methods.

What is Myopia?

Myopia is a condition in which the person cannot see distant objects. Short-sightedness occurs due to the formation of an image in front of the retina instead of on retina. Myopia is originated from the Greek word “Mumps” which means short-sighted. Therefore Myopia is also called short-sightedness. There are some causes of refraction of light and making an image in front of the retina than on retina which is inclusive curvature of cornea or lens, increases in axial length of the eye, increases in refractive index, the anterior position of the lens. Myopia has many types like congenital which is by birth, simple which is most common and starts from the age of 5-10 to 15-20 years, and this is due to curvature and length problem, pathological which is hereditary and progressive. Retinoscopy and A-scan Biometry methods diagnose myopia. Treatment of short-sightedness is possible by using a diverging lens like a concave lens, contact lenses and by the surgical approach in flattening of cornea and implantation of contact lenses.

Example

A student who is not able to see the counting or letters written on the classroom board is suffering from short-sightedness.

What is Hyperopia?

Hyperopia is defined as the condition or defect of the eye in which a person can see the far away things but is unable to see nearer things. Hyperopia is also known as hypermetropia. In this condition, the image is formed behind the retina of the eye. There are many causes which creates the image behind the retina of the eye these are the curvature of lens and cornea is flattened than the regular, short axial length of the eye, decrease in refractive index and posterior position of the eye lens. Hyperopia is also called long-sightedness. There are also different types of hyperopia like total hyperopia, latent and manifest hyperopia. This type of defect is also diagnosed by A-scan Biometry and retinoscopy. Hyperopia can be treated by using the diverging convex lens, by making cornea central curve part more curved by the surgical methods.

Example

A person is suffering from the hyperopia if he cannot read the book in his hand.

Key Differences

  1. In myopia, one cannot see the things which are far and can see the near objects clear while in case of hyperopia one cannot see the closer things but can see far objects clear.
  2. In myopia ray of light refracted in this way that it makes the image in front of retina while in case of hyperopia, a beam of light refracted in the direction that it makes the image behind the retina of the eye.
  3. In treatment, concave lenses are used in myopia, and convex lenses are used in hyperopia.

Comparison Video

Conclusion

This article concludes that both myopia and hyperopia are the defects of the eye. Myopia is also known as short-sightedness while hyperopia is called long-sightedness or hypermetropia. Both the defects of sight can be treated by refractive lenses, contact lenses, laser treatment, and surgical methods.

Janet White

Janet White is a writer and blogger for Difference Wiki since 2015. She has a master's degree in science and medical journalism from Boston University. Apart from work, she enjoys exercising, reading, and spending time with her friends and family. Connect with her on Twitter @Janet__White


View an animation to understand the science behind nearsightedness (myopia) and farsightedness (hyperopia)

The eyes are our windows to the world. They are optical masterpieces that can process pools of light coming from different distances in an instant when they are young and healthy. Eighty percent of the impressions our brains receive from our surroundings are relayed from our eyes, yet 40 million Germans have vision problems. Near-sightedness and far-sightedness are the most common vision problems. Our eyes actually work like this: In a person with normal vision, parallel light rays enter the eye and converge at one point on the retina. Near-sighted people's eyeballs are too long in comparison and the light rays converge in front of the retina, i.e. before they should. Despite its great flexibility, the eye lens is unable to compensate for this error. In this case, vision must be corrected using external aids. If vision is not corrected near-sighted people can only see blurry images in the distance. Eyesight often deteriorates very slowly, so slowly that many people fail to realize it at first. Far-sightedness is the exact opposite. When people are far-sighted their eyeballs are simply too short and the rays do not converge until they are past the retina. Up to a certain degree the lens can compensate for this by consciously focusing. However, as we age, we start to lose the ability to do this. When reading the paper you start to feel your arms have become too short and the letters are nothing but a blur. The only way to see properly now is with a vision aid.

You can have your vision tested by an eye doctor or optician. They will give you a value in diopters, which is a unit used to measure the error in the refraction of light. The divergence from the norm is negative for near-sighted people and positive for far-sighted people. The refractive error must be offset to correct vision impairment. One way to do this is with glasses. Contact lenses are another alternative, but you have to make sure you have plenty of tear fluid so the lens does not suction to your cornea. The only way to permanently improve your vision is to have corrective eye surgery. When this is done either a small part of the inner cornea is carved away or a special contact lens is implanted in front of the lens of the eye.


Chapter 10 Senses - Review Guide

2. Distinguish between the Meissner’s corpuscles and the Pacinian corpuscles.

3. Describe acute pain, chronic pain, viscerial pain, and referred pain.

4. What is the difference between a somatic sense and a special sense?

5. How can pain be managed (name natural chemicals and pharmaceutical ones)?

6. Define and give an example of sensory adaptation.

7. What are olfactory receptors and where are they located?

8. List the four different types of taste sensations. What is umami?

9. Describe the path sound waves take within the ear and are eventually processed by the brain.

10. Compare static equilibrium to dynamic equilibrium what part of the ear maintains your equilibrium?

11. Be able to label the ear identify which parts are associated with the outer, middle and inner ear

12. What is the difference between rods and cones?

13. Describe how we see images and the part of the brain that interprets those images

14. Know what the blind spot is, where it is located and why it exists at all

15. Define refraction and discuss how it affects your vison. What is the fovea centralis?

17. What is myopia, hyperopia and astigmatism? What is a cataract?

18. What are the muscles that move the eye called (also know locations).

19. Label the parts of the eye on a diagram and know the functions.