Who can calculate the power of the toric lenses?

[karimretina]

Dear guys,

What is the rule in calculating the powr of soft contact lenses especially the toric and bifocal contact lenses.E.g. if the spectacles are as follows:
-1.00 -2.00X180 (for toric soft contact lenses).
-5.00 -2.00X90 (for toric soft contact lenses).
+1 sph. +1.00cyl X 90 , Add +2.00 (for bifocal soft contact lenses)
-4.00 +1.00 X 180 , Add +3.00 (for bifocal soft contact lenses)

Thanks in advance

Khaled

[chip anderson]

First lens requires no caluclation, order as written or observe rotation with trial and then order axis adjusted for rotation
Second lens use -4.75 (or 4.62 if you can get it) with -2.00 or -1.75 cylinder.
Third lens use +2.00 -1.00 (0r -0.75) x 180 add may very some mfg. recommend a little less or a little more depending on model.
Fourth lens -3.00 -1.00 (or -0.75) x 090 good luck on getting a +3.00 add to work on any soft bifocal.

There are times when a rigid lens is the best answer, even a few when glasses are indicated.

Chip