Visual acuity is what most people think of when considering how well your eyes function. The standard for measuring visual acuity is an eye chart test, which measures the clarity of vision at a distance of 20 feet.
20/20 vision is what eye doctors consider to be “good or normal” vision. Contrary to popular belief, this number is technically not considered “perfect” vision. It’s possible for some individuals, mostly children, to have better than 20/20 vision.
Nevertheless, 20/20 vision is what eye doctors aim to achieve with corrective lenses or procedures. Estimates indicate that about 35 percent of the population has 20/20 vision without corrective lenses or surgery. With corrective measures, about 75 percent of adults have what is considered “normal” visual acuity.
What Measurements Make Up Perfect Vision?
Visual acuity is the clarity or sharpness of vision and includes your ability to recognize small details with precision. It’s the most common clinical measurement of visual function and one of the first tests during a comprehensive eye exam. Eye doctors use a standard eye test to measure visual acuity.
Clinicians consider a visual acuity test result of 20/20 to indicate “normal” or average vision. You’ve probably heard someone state that they have “perfect 20/20 vision.” However, some people have 20/15 or 20/10 vision, which is considered better-than-average vision.
So-called perfect vision is also more than the results of one acuity test. Other test results must show that you are not color blind, that your peripheral field of vision is strong and that your depth perception is solid.
You would also need to have high visual sharpness.
What Does 20/20 Vision Mean?
After completing a visual acuity test, you get results as a fraction. Normal visual acuity is considered to be 20/20 vision, which means you can be able to see clearly at 20 feet details that should normally be visible at that distance. The standard distance is 20 feet since that’s considered the distance where healthy eyes should be able to see while relaxed with no strain.
What Do Vision Measurements Mean? What Measurements Mean Perfect Vision?
Eye doctors utilize standard eye charts to measure how well you can see at a distance. This is where vision measurement, denoted as fractions, originate from. The Snellen eye chart is the most commonly used chart. The top number refers to the distance from the eye chart, which is typically 20 feet.
The bottom number refers to the size letter on the chart that you can read. It indicates the distance a person with normal vision would have to be to read the same line. Below is an overview of the various vision measurements:
- 20/15 vision: Better than average visual acuity. Other people would have to stand at 15 feet to see what you see clearly at 20 feet.
- 20/20 vision: Normal visual acuity. You can see what an average person with healthy eyes should see at 20 feet.
- 20/40 vision: Below average vision. The line you can read clearly at 20 feet can be read by an individual with normal vision at 40 feet.
- 20/80 vision: Poor vision. An individual with normal vision standing at 80 feet can read what you can only read clearly at 20 feet.
- 20/200 vision: Considered legally blind.
Is There More Perfect Vision Than 20/20 Vision?
Although 20/20 vision is considered normal or good vision, some individuals have visual acuity better than 20/20. Many young individuals, especially children with healthy eyes, have 20/15 or even 20/10 vision. Anything under this is considered the pinnacle of visual sharpness, although it’s very rare.
Why 20/20 Vision Is Not the Only Measurement That Matters
A visual acuity test is just one component of a comprehensive eye exam. Visual function is the measure of the performance of components of your visual system.
Visual tests analyze aspects including visual acuity, peripheral awareness, depth perception, eye coordination, focusing ability, motion perception, and color vision. These aspects collectively influence your overall visual function. The tests are an integral part of an eye exam that helps check for eye conditions and diseases.
How to Improve Vision
Improving your visual function starts with getting regular eye examinations to diagnose and treat any problems with your vision. Below is an overview of other ways through which you can improve your vision:
- Corrective lenses or surgery. Wearing prescription eye lenses or undergoing LASIK surgery can improve your vision if you have refractive errors including nearsightedness and farsightedness.
- Perform eye exercises. Research indicates that eye exercises can help visual acuity.
- Frequent blinking. Extended screen time often reduces your blink rate. Conscious blinking helps restore the tear film in your eyes, which can improve your visual clarity.
How to Maintain Your Eye Health and Vision?
The following are recommended practices and tips for maintaining your eye health and visual function:
- Regular eye checkups. Comprehensive eye exams help diagnose eye conditions and diseases to facilitate early treatment.
- Healthy diet. Your diet plays a vital role in eye health. It can help lower your risk of developing certain eye conditions and diseases. Practice a healthy diet that includes vitamins A, C, and E, omega-3-fatty acids, antioxidants, carotenoids, and zinc.
- Quit smoking. Smoking increases your risk of eye diseases, including cataracts and macular degeneration.
- Protective eyewear. Wear sunglasses to protect your eyes from UV light. Wear safety goggles or glasses during certain activities such as construction work or sports.
- Proper lens care. If you wear corrective lenses, always practice proper eyewear hygiene.
- Rest your eyes. Reduce your screen time and rest your eyes frequently during prolonged computer use.
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What is 20/20 vision? (May 2018). University of Iowa Hospitals & Clinics.
Keep Your Eyes Healthy. (May 2021). National Eye Institute.
Top foods to help protect your vision. (August 01, 2013). Harvard Health Publishing.
Benefits of Vision Correction with Contact Lenses. (May 2021). Centers for Disease Control and Prevention.
LASIK American Refractive Surgery Council.
Microscopic Eye Movements Improve Visual Acuity. (February 2020). American Journal of Managed Care.
Last Updated March 23, 2022
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