A free, simple, and easy to use app to calculate the equivalent lens of eyeglasses prescription at various Vertex Distances. It helps ophthalmologists, opticians, and eye care professionals to adjust spectacles prescription accurately according to the required Vertex Distance.

Features:
* Calculate the compensated (effective) lens power depending on the selected vertex distance.
* Calculate the values for both sphere and cylinder component of the lens.
* Calculate the Spherical Equivalent of the compensated lens power, so it can be used for contact lens e.g.
* Rounding the result lens to nearest standard lens power in 0.25 diopter steps.
* Convert easily between spectacles and contact lens prescription.