1-Progression Length = Total length from fitting cross to the near point Also called the Corridor Length
2-Minimum Fitting Height = Layout Reference Point to bottom of near circle
D-Distance Reference Point (DRP) = 6 or 8 mm
13135 66th Street North, Largo, Florida 33773 U.S.A. Tel. 00.1.647.722.6532 Ext. 525
sc@lensdesigners.com