71m/m Low Placement Rd. 22 m/m Bi-focals

 

Semi-Finished:

Material: CR-39*

                                                 

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

 

Additions:

.50 thru 10.00 in .25 steps (ex. 1.25, 1.50, 1.75, 2.00)

 

Higher additions available upon request

 

71 m/m (10.25 Base) in .50 steps only

71 m/m Extra Thick also available

 

Material: CR-39* Plastic                                                                      Specific Gravity: 1.32

Index of Refraction: 1.498                                              Low Placement Rd. 22m/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.-22      71m/m               2.00          2.00              2.25        1.191        11.2          11.5              0.0        12.5

Rd.-22      71m/m               4.25          4.25              6.25        2.573          9.0          10.4              0.0        12.5

Rd.-22      71m/m               6.25          6.25              6.25        3.864          8.2          11.5              0.0        12.5

Rd.-22      71m/m               8.25          8.25              6.25        5.240        10.8          11.5              0.0        12.5

Rd.-22      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.