Optical measurement of surface elastic wave designed for noncontact intraocular pressure measurement

Abstract

This study conducted an experiment to measure the elasticity related to intraocular pressure. When the intraocular pressure rises, the high intraocular pressure causes glaucoma, and the elasticity of the eyeball increases. This elasticity is to be measured according to the speed of the elastic wave. A 532 nm pulsed laser is used to generate acoustic waves with the principle of laser ultrasonic. By placing the probe using an interferometer at two points, the velocity and elasticity are recalculated using the time difference when the acoustic wave passes through the two probes. Since the distance between the two probes is constant, and the elasticity is low, then the time difference between the signals observed by the two probes is long. Other way, if the elasticity is high, the time difference observed is short. This will be applied to the measurement of intraocular pressure in the future.