<unk> , also known as photokeratoscopy or videokeratography, is a non-invasive medical imaging technique for mapping the anterior curvature of the<unk>  the outer structure of the eye. Since the<unk> is normally responsible for some 70% of the eye's refractive power, its<unk>  is of critical importance in determining the quality of vision and<unk>  health. The three-dimensional map is therefore a valuable aid to the examining ophthalmologist or optometrist and can assist in the diagnosis and treatment of a number of conditions; in planning cataract surgery and intraocular lens implantation; in planning refractive surgery such as LASIK, and evaluating its results; or in assessing the fit of contact lenses. A development of keratoscopy,<unk>  extends the measurement range from the four points a few millimeters apart that is offered by keratometry to a grid of thousands of points covering the entire<unk>  The procedure is carried out in seconds and is painless.
Corneal topography
Corneal pachymetry
Scanning laser ophthalmoscopy
Doppler optical coherence tomography
Ocular tonometry
Eye testing using speckle
Exophthalmometer
Retinal birefringence scanning