A High Efficiency Optical Power Transmitting System to a Rechargeable Lithium Battery for All Implantable Biomedical Devices

A novel power supply for medical implants has been developed. Using wireless technology secondary battery of power supply for implanted devices is recharged using laser diode, which transmits power in near infrared region. Transmitted power is received by photo voltaic cell array embedded under skin and charges the secondary battery, which in turn charges primary battery providing power to the implanted device. Experiments carried out have shown that, a photo diode with surface area of 2.1 cm2, emitting light in near infra red region at 810 nm wavelength with power density of 22 mW/cm, provides sufficient energy within 17 min to allow regular commercial cardiac pacemaker to work for 24 hrs. During continuous irradiation for 17 min on skin, temperature rise is only 1.4°C which is acceptable. Thus this wireless technique can be implemented for the benefits of patient.