how to calculate of power lens ?

Question

I have a prescription to make a power lens.

What will be the best possible equation to find the Total Power Lens according to the prescription.

Answer 1

A dioptre, or diopter, is a unit of measurement of the optical power of a lens or curved mirror, which is equal to the reciprocal of the focal length measured in metres (that is, 1/metres). For example, a 3 dioptre lens brings parallel rays of light to focus at 1/3 metre.