Refraction – Degrees for Contact Lenses

Refraction for contact lenses differs from refraction for eyeglasses.

For the examination, the following are used: refractometer and sample lenses to find the degrees of refractive error and visual acuity, keratometer to measure corneal curvature and special strips for quantitative and qualitative evaluation of tear.

For the application of rigid gas permeable and hard contact lenses, especially in cases of keratoconus, corneal topography is often required.