So, is your eyesight 20/20? Do you have visual acuity?
I have 20/20 eyesight, just had it checked last week. 
The eye charts used were developed in 1862?
Wow, I did not know that. That was a long time ago. One of the oldest professions. 
Yes.  It is. Visual acity is dependent also on the  sensitivity of the interpretive faculty of the brain.