Patent ID: 8796886

Claim:
A wireless power transmission unit comprising: a varying frequency excitation source arranged to provide a variable circuit excitation at frequency f; and a first resonator structure coupled to the varying frequency f power supply, the first resonator structure having a resonant frequency ω 1 , a first Q factor Q 1 , and a characteristic size L 1 wherein non-radiative energy transfer between the first resonator structure and at a second resonator structure positioned apart from the transmission unit, the second resonator structure having a resonant frequency ω 2 , a second Q factor Q 2 , and a characteristic size L 2 is mediated through a magnetic resonant coupling associated with evanescent tails between the first resonator structure and the second resonator structure when the first resonator structure and the second resonator structure are in a tuned state when the first resonant frequency Γ 1 and the second resonant frequency ω 2 are within the narrower of first resonance width Γ 1 or second resonance width Γ 2 such that the first resonant frequency ω 1 and the resonant frequency ω 2 are separated by a bandwidth of no more than 3db, wherein the first resonator structure maintains the first resonator structure and the second resonator structure in the tuned state by varying the first resonant frequency ω 1 such that the first resonant frequency ω 1 and the resonant frequency ω 2 are separated by the bandwidth of no more than 3db or are within the narrower of first resonance width Γ 1 or second resonance width Γ 2 in accordance with any changes in the second resonant frequency ω 2 .