Easily check your own prescription.
In many respects this calculation is more accurate than computerized photoropter measurements at the optic shop, and even more detailed than looking at a Snellen chart.
I created this simple calculator for you:
Centimeter Calculator Version 0.1[/caption]
It is quite simple to use:
1. Take off your glasses.
2. Use the instructions to find where the text on the screen just barely starts to blur.
