Tonometry is a diagnostic method which, through the use of different tools, allows the evaluation of the pressure existing inside the human eye. An elevated intraocular pressure (IOP) is the main risk factor for the development of glaucoma, an ocular disease, that if properly treated, causes irreversible damage to the optic nerve, leading to blindness. The aim of tonometry is to detect the IOP that is measured in millimeters of mercury (mmHg); it is performed through the interaction with the ocular structures and in particular with the cornea.