Re. 20/20 vision...?

Question

I found an explanation of what '20/20' means here: http://health.howstuffworks.com/question126.htm

My question is how can I translate my prescription into that? I am around -6 or -7D, that would be 20/??

Answer 1

The 20/20 value is your visual acuity.

The -6.00 is the power you need to bring you back up to 20/20...or as close as possible.

Your visual acuity is a complete different measurement and can be affected by several variables such as astigmatism.

Presuming you have straight, simple myopia of - 6.00 , that would normally give about 20/800 uncorrected vision...a - 7.00 would be closer to 20/1000

But, as I said, that is an approximation, the exact visual acuity can't be found just be knowing the prescription.

It's kind of like comparing apples and oranges...one measurement doesn't always equate to the other.

Your actual visual acuity would be known by your Dr. after seeing the results of the eyechart measurements.