Contact Lenses The Science Of PRECISION1® With SMARTSURFACE Technology Apr 02, 2021 Dr. Katie Gilbert-Spear, OD, JD, MPH Related Publications Importance of Rotational Stability and Tear Film Stability in Toric Contact Lens Wearers Contact Lenses Astigmatism occurs when light entering the eye does not converge at a single focal point in the back of the eye, but instead focuses at two different locations. Learn More ↑