Hello!
This is Spectacle magnification equation:
SM=[1/(1-(t/n)*Df)]*[1/(1-h*D)]
where h is verteks distance ("Vertex distance is the measurement from the back of the spectacle lens to the front of the eye", that means to the apex of the cornea
- http://onlineopticianry.com/wordpres...p2pdf.php?p=37 ).
But, in several places I find that this "h" ("g" or "d") is "distance from the back of the lens to the entrance pupil" ( http://www.drdrbill.com/downloads/op...nification.pdf )
Can someone explain me this difference?
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