eyesight measurement?!
Question:
how are they calculated?
Answers:
THE DOCTORS LET THE PEOPLE TO LOOK IN THE "SNELLEN CHART" WHICH IS A TEST..YOU WILL JUST LOOK AT THE CHART AND TRY TO READ THE LETTERS WRITTEN IN IT..THE LETTERS HAVE DIFFERENT SIZES..NORMAL VISION IS 20/20 VISION..LOWER THAN 20/20 LIKE 10/10 IS A GREAT VISION..HOWEVER..HIGHER THAN 20/20 MEANS THAT YOU HAVE POOR EYESIGHT.
Answers: