Patent ID: 7751170

Claim:
A method for transferring charge to or from an electrically isolated test body, the method comprising: disposing a reference body in proximity to said test body; applying a modulated electrical bias between said test body and said reference body; illuminating said reference body and said test body with modulated optical radiation; wherein said modulation of said electrical bias and said modulation of said optical radiation are phase coherent; wherein a wavelength of said optical radiation is sufficiently short that charged particles are emitted from surfaces of said test and reference bodies illuminated by said optical radiation; wherein said emitted charged particles move between said reference body and said test body in response to said electrical bias; wherein one or more parameters of said modulated electrical bias and of said modulated optical radiation are selected to set a magnitude and direction of a charge transfer rate between said test body and said reference body; wherein said parameters include a phase relation between said electrical bias and said optical radiation.