A method for reducing body exposure to electromagnetic field of pillow type wireless charger in fully implantable middle ear hearing device

Abstract

Implantable middle ear hearing devices (IMEHDs) have been developed at several countries. Some devices can be selected rechargeable battery for long-term implant. In South Korea, a kind of IMEHD with rechargeable battery and a pillow type wireless charger have been developed. The charger includes several coils surrounding user's head in sleep. However, this device should excessively consume power due to driving all primary coils. Especially, needless exposure to magnetic field generated from uncoupled primary coils may induce bio-hazards. Therefore, a method reducing the body exposure to electro-magnetic field was proposed as decreasing the emitted total magnetic flux during charge process. © IEICE 2009.