uBeam: This far field wireless charging system uses ultrasound to transmit power – Energous, Ossia and PowerCast (see below) use radio frequency (RF), while Wi-Charge uses infrared (IR) – and has been mired in controversy as a potential scam for a year or so. But at CES, uBeam seems to have re-emerged with a new CEO and actual working equipment, such as this demo at CES in which some LED lights received power from a transmitter a few feet away.