A simple app to calculate the eyeglasses lens equivalent by 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.