A new electronic tonometer for ocular epipalpebral measurements.

A new electronic tonometer is presented in this paper. This is an electromechanical device that has been designed to establish, by means of a fully automatic process, an approximate value of the intraocular pressure (IOP) without the need to be handled by an ophthalmologist. It can be applied on the closed eyelid with no danger for the patient in an easy and simple way. These have been the main prerequisites for the proposed tonometer in order for it to be used in the future in the same way as domestic clinical thermometers are used nowadays. The main benefits obtained with this measurement is a much earlier warning in cases where incipient glaucoma is already carving its silent way to an unexpected future blindness. The tonometer can also be used and has been employed as a research instrument, placed either on the eyelid or on the cornea, and a substantial flow of data on how IOP evolves is obtainable by computerized means. The tonometer is based on a microcontroller device, which is the electronic core of the equipment that manages the user interface, runs the complete test, and shows the final results. This paper describes the design in a stage previous to the "domestic tonometer": a laboratory prototype to obtain physical properties of the eye under a variable static, radial, and epipalpebral force.