Appliance for calibrating and checking tonometers

摘要

A plastics membrane (1) forms the measurement surface and the critical point in the design is the support surface (2) of the membrane on the pressure chamber of the appliance. The chamber is filled with fluid under pressure applied by a syringe and monitored by a manometer connected to a pressure connection (7). The membrane has a diameter corresponding to the mean cornea diameter and a curvature to that of the mean radius of the cornea.