A tonometer, which involves no mechanical contact with the eye, has been designed and is being tested. An air pulse generated from the ambient atmosphere with a reliable positive linear force-time ramp inpinges upon the cornea. The pulse causes a gradual curvature reduction, applantion, and finally a slight concavity before the decaying force-time ramp permits restoration. Telecentric optical-electronic monitoring of the corneal vertex specular reflection uniquely identifies, in time, the applanation event.Both human and animal testing have demonstrated a direct linear relationship between intraocular pressure and the time interval to applanation. This permits instantaneous digital readout in mm Hg. An optical-spherometer type system is utilized to effect alignment of the pneumatic and monitoring systems with the cornea in three dimensions. Following alignment and triggering, measurement in the normal range takes approximately 3 milliseconds, does not require lid retraction, and induces only a blink reflex with no discomfort.