Cooper Clear Toric contact lenses from CooperVision are spherical lenses designed to be worn as daily wear contacts, removed and cleaned nightly. These lenses are manufactured to provide clear and comfortable vision to patients suffering from astigmatism. The lenses are worn for up to a year.
Lens Material
The lens material, tetrafilcon A, is a hydrophilic random terpolymer of 2-hydroxyethyl methacrylate, N-vinyl-2-pyrrolidone and methylmethacrylate joined in a three dimensional network of terpolymer chains by divinylbenzene cross links.
| Lens Parameters | |
| Base Curve: | 8.0 to 9.6 mm |
| Diameter: | 13.5 to 15.5 mm |
| Sphere Power: | -20.00 to +10.00 D |
| Cylinder Power: | -0.50 to -9.00 D |
| Center Thickness: | 0.04 to 0.52 mm (varies with power) |
| Lens Properties | |
| Refractive Index: | 1.43 |
| Light Transmittance: | 97% |
| Surface Character: | Hydrophilic |
| Water Content: | 42.5% |
| Oxygen Permeability: | 9.3 x 10-11 (cm2/sec) (ml 02/ml x mmHg) at 35 deg. C |