20/20 vision

What is 20/20 vision ? 20/20 is American for 6/6. The first number is the testing distance and in the UK we use 6 metres.

Lets see what its like. A test chart that optometrists use is the best place to start. The line with red is the 6/6 line. Most people should be able to see below this line! Please note that this is very simple and there are many other aspects to seeing well.


	From 6 metres this is what a chart looks like to a person with 6/4 vision


		This is what a person with good vision would be likely to see.



			Yes this is Waterworks, I’ll need to take the next exit.


	From 6 metres this is what 6/9 could look like.


	And this is still legal to drive.




		Is this Waterworks Corner ? Can’t tell so I’d better move over just to be safe.


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