It’s inevitable that at some point in your lifetime, you’ll have to take an eye exam. If you have perfect vision and end up passing your eye exam with flying colors, you probably won’t have to take one again until you have a need to visit an optometrist… which could be a long while as you grow into your adult years. If your eye exam yields issues, however, it’s likely going to be one of many that you’ll experience throughout your lifetime.
But what are eye exams in Oshkosh, really? The tests can seem strange and arbitrary to the person taking them and at the end of it all, your eyesight is given a grade that not even you might understand! So what exactly is going on when you take an exam?
Understanding an eye exam
For most generic eye exams in Oshkosh, you’ll be presented with a poster of letters that you’re expected to read. The letters keep getting smaller by row and each row has more than the last—there are usually 11 total rows. This is called a Snellen eye chart, and it’s a standard that helps to test the clarity of your vision.
Now, the magic behind this eye test is the distance at which you stand from it, versus your ability to read letters as they get smaller. The top row—which is usually a solitary letter “E”—is the benchmark for 20/200 vision, with perfect 20/20 vision coming by line eight. The standard for getting a driver’s license in the United States, for comparison’s sake, is 20/40, which would be row five of the eye chart.
What does 20/20 or 20/40 or 20/200 actually mean? Well, it’s based on a measurement standard that gauges your ability to read that letter from 20 feet away based on the distance you should be able to read it from:
- 20/20: You can read a letter at 20 feet away that most other people can also read from a 20-foot distance.
- 20/40: You need about half the distance closer to read a letter that most people can read from 20-feet away.
- 20/200: Your eye sight and visual acuity are extremely poor—you need to be 10x closer than most people to see a letter clearly.
How does an eye test translate?
The results of eye exams in Oshkosh don’t directly translate into glasses or contact lenses that correct your vision—numerous other variables are required to gauge what your astigmatism is and how it can be corrected. Traditional eye exams simply give optometrists a starting point. Depending on how severe your vision issues are, they can begin to test and observe other variables that will eventually translate into corrective lenses.
When you get a prescription that says -4.5 or +2.0 on it, this isn’t necessarily a representation of your eye exam—it’s a cumulative measurement of numerous tests run to gauge your eyesight. Things like refractive power, base curve, diameter, cylinder and magnification are all taken into account when it comes to prescribing things like contacts. And, where a standard Snellen eye chart can lend itself to one variable (magnification), a complete assessment will be needed to further determine the best way to correct your vision.