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What is 20/20 vision ?
20/20 is a mathematical standard of 1’ of arc separation between the limbs of a letter E when viewed at 20 feet.
In the UK, we changed the imperial measurement of feet into metres and then rounded to 6 metres. 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 and we have placed it on the left side with a scene on the right.
The line with red either side 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.
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