A team from the Massachusetts Institute of Technology (MIT) lit a 60 watt light bulb from a power source two meters away and with no physical connections between the source and the appliance.
The "WiTricity" device--the term coined by the MIT team to describe the wireless power phenomenon--uses magnetic fields to deliver power to the gadgets remotely.
The charger sends power to the gadget using magnetic induction, which is the ability to change a magnetic field to produce an electrical current.
Various methods of transmitting power wirelessly have been known for some time, such as radio waves or Wi-Fi.
But while such examples are excellent for the wireless transmission of information, it is not feasible for substantial power transmissions because radio waves and Wi-Fi radiation spread in all directions and vast amounts of power end up being wasted into free space.
In contrast, WiTricity synchronizes the charger and gadget to exchange energy efficiently without leaking much power to other objects.
WiTricity does this by getting the charger and power-hungry device to connect using magnetic fields at 'coupled resonant frequencies'.
Further geeky details at this link.
