Contact Lens Formulas Flashcards
1
Q
Contact lens as a thick lens
A
2
Q
Vertexing specs to CLs
A
More plus is necessary in rx when switching to CLs from specs
3
Q
Lacrimal lens
A
LL = BC - K
4
Q
Refraction and GP formula
A
SRxv = CLP + LL + OR
5
Q
Radius of curvature conversion
A
F = 337.5 / radius in mm
6
Q
Compensating power with BC change
A
SAM FAP
0.5D BC = 0.5D power = 0.1mm BCradius change =1mm change OAD (0.8mm for OAD in kmk)
7
Q
Residual astigmatism
A
RA = SRx cyl - Kcyl
has to be same axes
8
Q
Javals rule (exact)
A
Total cyl = 1.25(Kcyl) + (-0.50x090)
9
Q
Final CLP
A
Final CLP = DxCL + ORv
