The unit of measuring refraction is called Diopter; the higher the range of myopia, hyperopia or astigmatism, the higher the number. The way we measure the power of eyesight is put into 3 numbers.
For example: -5.00-1.50*180
The first number is the refractive power of the myopia or hyperopia , the - sign in front represents myopia and the + sign for the hyperopia.
The second number is the astigmatism power which will also uses the "-" or "+" sign.
The third number is the degree or axis of the astigmatism.
So,5.00-1.50*180 means, 5 Diopter myopia, with 1.5 Diopter astigmatism at 180 degrees. |
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