Implantable auditory system with micromachined microsensor and microactuator

摘要

An implantable auditory system for a human subject includes a microsensor, a processor and a microactuator. The microsensor is implanted in the middle ear to transduce sound waves into electrical signals. The processor is implanted in a hole surgically sculpted in the skull and controls amplification and processing of the electrical signals. The microactuator is micromachined from a single crystal and acts as a parallel plate capacitor, with a diaphragm spaced from the rest of the crystal by an extremely small void therebetween. The microactuator is implanted in the middle ear, and it may extend into the inner ear through a surgically formed fenestration or be mounted to the ossicular chain. Electrical signals conveyed to the microactuator set up electric fields across the narrow void and the diaphragm to produce electrostatic forces that cause the diaphragm to vibrate, thereby directly or indirectly vibrating fluid in the inner ear. Use of electrostatic forces to vibrate inner ear fluid reduces electrical current requirements, resulting in increased battery life.