A Noncontact Applanation Tonometer

Abstract

A new applanation tonometer (NCT) measures intraocular pressure without touching the eye. A central area of the cornea is deformed by an air-pulse of linearly increasing force and the instant of applanation is determined by a monitoring system that senses light reflected from the corneal surface. Clinical evaluation has demonstrated good correlation between NCT and Goldmann tonometer readings, thereby validating this new method of tonometry.