Driving Test Eyesight Rules:
At the start of your practical driving test, you will be asked to read a number plate from around 20 meters. The law states that driver’s must be able to read a clean number plate at 20.5 meters in good daylight.
So if your eyesight is week and you do not pass this eyesight test you will not be able to continue with the test. So it is better to get your eyesight checked and get a pair of glasses if needed before the test.