With Topcon's exclusive Rotary Prism Technology, the KR-800s 5 in 1 Auto Kerato-Refractometer delivers extremely accurate and consistent measurements. This versatile ophthalmic diagnostic device features several tests, including: Accurate objective measurement Far and near subjective VA measurement Glare test Grid test Contrast tes Topcon's Rotary Prism Technology: This exclusive technology is extremely precise and reliable, enabling measurement of an area of the retina while enabling pupils as small as 2 mm in diameter to be measured. 5-in-1 testing capability with tests for objective measurement, near and far subjective measurement, glare test, grid test and contrast test. Color touchscreen control panel with wide 8.5 inch display Smoother operation and movement than prior versions, 23% lighter than the KR-800 to enable a more fluid measurement process. Easy to load printer. Topcon's exclusive Rotary Prism Technology.