What does a 6/9 vision mean?

Q: I want to know what does a 6/9 vision mean? I had a 6/9 vision power and my doctor labelled my defect as astigmatism. Is it curable or preventable?

A:This means that the letters on the chart which should be read at 9 feet, you are only able to see at 6 feet. In other words you are only short of one line on the chart. We all have slight astigmatism and you should not worry about this at all. Glasses should improve the vision and relieve the eye strain or headaches if you are prone to it.