Exploring Visual acuity, eyesight, and vision.
Let’s begin with “visual acuity” and what that means:
Visual acuity. This refers to the sharpness of our vision. At some point in your life (and probably several times), you have sat or stood before a chart (at a given distance) with one eye covered and spoke or pointed according to what you see on this stationary chart. The letters or numbers remain motionless as well. This “test” is to determine your Visual Acuity or the sharpness of your vision.
Visual Acuity testing is typically done on high contrast situations with the eye chart configured as black letters or numbers on a background of white.
Although this method is quite conclusive to assess a person’s visual acuity or relative clarity of their eyesight in certain conditions, it fails to conclude your vision’s quality in all situations. Some of the areas the chart test fails to achieve are the:
- Ability to detect objects which are close in brightness to their background
- Ability to determine the color of objects
- Ability to identify moving objects
There are three main physical and neurological elements found to determine eyesight acuity:
- How precisely the cornea and lens of the eye direct light onto the retina.
- How well the nerves in the retina and vision centers in the brain receive the signals.
- How comprehensively the brain can decipher the information received from the eyes
There is actually only a minimal but sensitive area in the retina called the macula. Light is focused that influences the visual acuity measurements collected in the eye exam.
Eyesight. The definitive definition of “eyesight” is a challenge to conclude. Based on which source you use, dictionary or elsewhere, Eyesight can mean anything from “vision,” “ability to see,” “the sense of seeing,” “range of sight,” or “view.” And very often, “visual acuity” and “eyesight” are used alternately.
Vision. Being a broader term than visual acuity or eyesight, the term “vision” usually encompasses a broader scope of visual capabilities and strengths, including the competence to follow moving objects with steady and systematic eye movements, color recognition, depth perception, ability to focus quickly and precisely, etc.
So What is 20/20 vision?
“20/20” vision and similar fractions (such as 20/40, 20/60, etc.) are typical visual acuity measurements. These are named after a Dutch ophthalmologist called Herman Snellen, who developed this way to measure visual acuity in 1862.
The top number of the Snellen fraction (I.E., 20/20, 20/40/, 20/60) represents the viewing distance between the patient and the eye chart. In the United States, this distance usually 20 feet, but in other countries, that distance is 6 meters.
You are tested to see if you can identify the letters on one of the smaller lines near the bottom, which is standardized to “normal” vision. If you can correctly read the line, you must have normal (20/20) visual acuity.
With the increasingly larger numbers toward the top of the chart, the ability to read each line determines which fraction on the Snellen chart best describes your “visual acuity.” If the large E at the very top of the chart is ALL you can see clearly, it is determined that you are “legally blind.”
Is it possible to see better than 20/20?
Yes, it is possible, especially with the young whose eyes are very healthy and capable of correctly identifying letters or numbers on the 20/15 line of the Snellen chart.
Two types of “Vision” that are not measured with the Snellen chart are “Hindsight” and “Foresight.”
Do you know anyone with perfect “hindsight?” I think it would be safe to say we ALL have perfect “hindsight:” It is said that hindsight is 20/20. When we can reflect and be happy and proud of a choice we made or SAD because of a wrong decision, hindsight becomes very clear.
What about “FORESIGHT?’ Some seem to be blessed with this “sight,” which isn’t really a sight per se, but the ability to visualize and conceptualize an idea or dream.
It is truly and clearly evident that Henry has STRONG Foresight with Compumatrix, which cannot be swayed by time or challenges. His “vision” is far better than 20/20 and has the shrewdness and resourcefulness to see his dream realized for all who care to follow! God Bless Henry, a man whose VISION can be shared by all who wish to Engage, Enrich and Enhance the lives of our brothers and sisters around the world.