71m/m Round 35m/m Bi-focal

 

Semi-Finished Material: CR-39*

 

Base Curves: 2.00, 4.25, 6.25, 8.25, 10.25

 

Available in 71m/m Blanks only

 

Additions:  .50, .75, 1.00, 1.25, 1.50, 1.75, 2.00, 2.25, 2.50, 2.75, 3.00, 3.25, 3.50, 3.75

 

Higher additions also available upon request

 

Material CR-39* Plastic                                                 Specific Gravity: 1:32

Index of Refraction: 1.498                                       71m/m Rd. 35m/m Bi-focal
Abbe Value: 58

 

Note:*

 

Lens         Actual         Nominal      Actual             Back           Sag                                               Seg        Seg

Style         Size                  Curve       Curve           Curve       50m/m         C.T.           E.T.           Inset        Drop

 


Rd-35        71m/m                  2.00           2.00               2.25         1.191         11.2           11.5               0.0        4.0

Rd-35        71m/m                  4.25           4.25               6.25         2.573           9.0           10.4               0.0        4.0

Rd-35        71m/m                  6.25           6.25               6.25         3.864           8.2             7.4               0.0        4.0

Rd-35        71m/m                  8.25           8.25               6.25         5.240         10.8             7.4               0.0        4.0

Rd-35        71m/m                10.25         10.25               6.25             **           **             **               **        **

 

Note: *Over 10.00 Diopter addition adds THICKNESS and changes ALL BACK CURVES to -2.25.

Note: **Information Not Available At Press Time.