What do the numbers on eyeglasses mean?+1.00,+2.50?etc,etc?!
Question:
What do the numbers on eyeglasses mean?+1.00,+2.50?etc,etc?
is like 1.00 the weakest and it goes up from there?
Answers:
Well the numbers in a prescription basically just mean the power needed in the lens to get the light to focus on the retina to obtain clear vision!
Just to put it simply: when a person is farsighted/hyperopic their eyeball is too short and the light comes into focus behind the retina. To correct this a plus (+) powered or converging lens is needed to bring the light back to focus on the retina.
When a person is nearsighted/myopic their eyeball is too long and the light focuses in front of the retina. To correct this they need a minus (-) powered or diverging lens to bring the light into focus on the retina.
The number in a persons prescription is just the strength of lens needed to bend the light to focus on the retina.
Technically 0.00 or plano is the lowest number and has no correction. From there it goes up in quarter increments +0.25,+0.50,+0.75,+1.00 etc.... The same goes for minus prescriptions -0.25, -0.50, -0.75, -1.00 etc... and they can get pretty high like prescriptions like -18.00 exist for example!
Anyways hope this helps a bit :)