Ultrasound as a New Wireless Power Transfer Technology

With the increasing demand for underwater and implantable medical electronics, a stable and continuous power supply is essential. However, conventional wireless charging methods (such as electromagnetic induction and radio frequency-based charging) used in smartphones and wireless earphones suffer from short transmission distances, low energy transfer efficiency in biological tissues, and electromagnetic interference. To overcome these limitations, researchers are now considering the use of ultrasound as a new wireless power transfer technology. Ultrasound has the advantage of being human-friendly and less absorbed by tissues, allowing for more reliable energy transfer in implantable and skin-adherent devices. As a result, wireless charging technology utilizing ultrasonic energy is emerging as the next generation of power transfer.