The difference between long sightedness and short sightedness

If you’ve ever assumed long-sightedness is the ability to see far away but not up close. Whilst short-sightedness is the opposite, you wouldn’t be the only one. However, the difference between long and short-sightedness is not as straightforward as one experience being the opposite of the other.

A Little Bit of Eye Anatomy

There are several anatomical components that are involved in the creation of vision. This isn’t even going into the visual processing and interpretation that takes place in various parts of the brain. From an anatomical perspective, to achieve sharp vision light must pass through:
  • The tear film at the interface between the surface of the eyeball and the air
  • The cornea, which is the transparent dome of tissue at the front of the eye
  • The fluid between the cornea and the crystalline lens behind the iris (the coloured part of the eye). This fluid is called aqueous humour
  • The crystalline lens. This lens is suspended behind the iris with fibres known as zonular fibres and attached to a ring of ciliary muscle. This lens is able to change its shape and thereby change the focus of light. By tensing or relaxing the ciliary muscles in a process called accommodation
  • The gel between the lens and the retina at the back of the eye, called the vitreous humour
After passing through all these optically transparent media, light rays must then focus to a point right on the retina. In order for us to perceive our sight as clear and sharp.
In a perfect eye, the degree of refraction (bending) of light through all the components mentioned above matches the physical length of the eyeball. Such that without any effort, when the eye is fully relaxed and looking into the distance, light will naturally focus to a sharp point right on the retina.
Refractive errors and eyesight problems – such as long-sightedness and short-sightedness – arise when these factors do not match up.

The Difference Between Long Sightedness and Short Sightedness

Short-sightedness, also known as myopia, occurs when the length of the eyeball is too long for the refractive power of the eye. People with short-sightedness will tend to find that their near vision, such as for reading, is clear with no spectacles or contact lenses. While optical correction is required to see objects in the distance to gain clear distance vision. This holds true only for some people with increasing age, depending on the degree of their short-sightedness.
At some point, a person with a low degree of short-sightedness will find it difficult to focus on objects yet will still need a reading prescription as they get older. This occurs if a person’s normal age-related decline in near vision (presbyopia) exceeds their natural ability to see up close. Patients with moderate degrees of myopia may find they can retain clear reading vision by simply removing their distance glasses.
Long-sightedness, or hyperopia, works a little differently, but can be considered opposite to myopia. In the way that long-sightedness occurs when the length of the eyeball is too short for the power of the eye. You may have noticed that out of the refractive components listed above, only one could be controlled. The power of the lens during the process of accommodation. When we are young, the lens is flexible and accommodation is quite active.

Age and vision

Young patients with long-sightedness (i.e. long sighted people) often find that their sight remains clear and comfortable. Both at a distance and near, depending on the magnitude of their prescription. However, it means that even to view distant objects the eye is exerting an accommodative effort to clear the vision. This effort in adjusting the focus increases when viewing objects as they come closer.
As we get older, the lens naturally becomes stiffer and slowly loses its accommodative ability. This is why many people notice difficulty with their reading vision around their mid-40s as presbyopia sets in. Because patients with age related long sightedness are already relying on accommodation to see at a distance and even more so for nearby objects. Depending on the degree of long-sightedness, they will eventually find that both their far and near vision will deteriorate with age. They may need spectacles for both activities to ensure the eye focuses as it should, likely starting with near vision first.
There are several solutions to address refractive errors as well as conditions such as lazy eye (which can also make objects look blurry). This can be in the form of contact lenses or eyeglasses. Many long- and short-sighted patients may also be suitable candidates for laser eye surgery. If you have more questions, please call us at 0390 700 910

Share this post!

Home » Blog » The difference between long sightedness and short sightedness

Take this quick quiz to discover if you could escape the barrier of glasses and contact lenses

Not everyone can benefit from laser eye treatment – your options change depending on your eyes, age and lifestyle. Find out which type of treatment is right for you by taking this quick 2 min quiz:

Show me my suitability

Popular procedures

What our patients say...

“I’ve now got better than 2020 vision. No more glasses for me! I’m extremely pleased with the results.”
Ash Redward
“Dr. Anton and his team have been nothing short of amazing through my journey in achieving better than 20-20 vision. Thank you!”
Trish Toth
“Professional, thorough and gentle. Have been commending Dr Anton and the team to all my friends and family!”
Zac Puplett

“Lovely staff, great facilities, eye surgery went smoothly – definitely recommend!”

Kate Luscombe

Related Posts

About the expert

Dr Anton van Heerden, MBCHB; FRANZCO
Ophthalmologist & Laser Eye Surgeon

Based in Melbourne, but with a reputation that transcends borders, Dr Van Heerden sets the highest bar for laser vision correction surgery in Australia. While his skills and experience are second to none, it is his fun, caring and down to earth nature that truly set’s him apart from the rest. You can sit back and enjoy the journey knowing every detail has been carefully considered.