Eye Test for Myopia & Hyperopia
To take this test correctly, you must place yourself at a distance from the screen of approximately:
2.20m for a 20" screen,
1.50m for a 17" screen,
1m for a 15" screen,
75cm for a 14" screen.
Cover one eye with your hand, without pressing on the lid, and take the test. Cover the other eye and begin the test again.
Your distance vision is deficient if you see the O sharper or blacker, either in the red or the green color.
Generally, if you see the O blacker or sharper in the red part, you probably have myopia or have a myopic tendency.
Conversely, if you see the O blacker or sharper in the green part, you are definitely hyperope and have hyperopia.
In any case, an eyesight check by an eye care specialist would appear necessary.