DIA. 76 mm is unavailable with the progressive or bifocal lens

[mens glasses]

for example, one people's PD is 59mm, but he selected a large shape half-rim eyeglass frame which has size at 58-18-135.

After measured, it is a very complex technical, and moreover, the progressive or bifocal lens rescription Glasses Category - Progressives Eyeglasses - Prescription Glasses | Cheap Glasses| discount glasses leader online is unavailable with dia. 76mm.

But, how to measure out the workable diameter of lenses for bifocal or progressive prescription?