AUTO-KERATO-REFRACTOMETER
Nidek Tonoref II
This instrument is used to measure whether and to what extent an eye is short-sighted (myopia) or long-sighted (hyperopia). It can also detect an astigmatism. Before a prescription is written out for glasses, the phoropter (see below) is used to check whether the patient also sees better with this lens calibration and whether he is happy with it.
The measurements made using the auto-kerato-refractometer are therefore used as a starting point to decide what glasses you need.
The measurements can be made by the ophthalmic nurse before the doctor examines the patient.