Ophthalmic implants

The low power consumption of CMOS electronics with on-chip co-integrated sensors or actuators makes this technology ideal for the use in implanted systems that need a very low power consumption. Due to the successes in miniaturisation such systems are available for applications inside the eye. In this paper three developments currently worked on in Germany will be described. All systems are powered by the energy of an external RF-field. The first microsystem presented here is a system for measuring the intraocular pressure which is important for the therapy of patients having glaucoma. The second system, the so called retina implant, will help patients suffering from retinitis pigmentosa to get some visual information by stimulating retinal ganglion cells. After heavy accidents like an explosion the cornea often is damaged in such a way that there is up to now no possibility to repair it. For this kind of injury an implantable vision aid is in development by a German research group.