The NIDEK AUTO REF/KERATOMETER ARK-1s measures spherical, cylindrical refractive errors, and cylinder axis from the refractive status of the patient’s eye. In addition, subjective test is performed with the built-in charts and lenses for subjective measurement. The keratometer measures the corneal curvature radius (corneal refractive power), principal meridian directions, and corneal cylindrical power.
An electrically-powered, automated, ophthalmic device designed to measure the refractive error of the eye (the inaccuracies of focusing of light upon the retina) by measuring how light is changed when it enters the patient's eye(s). A beam of light is emitted from the device into the patient's eye and reflected back out where it is detected and measured for sphere, cylinder and axis, as well as high order aberration measurements; typically measured in dioptres (the reciprocal of the focal length of the lens expressed in metres). Using this information, the device, also known as an aberrometer, will automatically calculate the lens prescription needed to correct the patient's vision.
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