Device for generating RF energy from electromagnetic radiation of another form such as light

A device for generating RF energy from electromagnetic radiation comprising emitter means responsive to the electromagnetic radiation for producing a beam of charged particles, an electrode spaced from the emitter means, the emitter means and the electrode defining a path therebetween along which the charged particles move, and a resonant structure for supporting RF oscillations disposed between the emitter means and the electrode and positioned with respect to the path so as to enable continuous energy transfer from the charged particles to an RF field associated with the RF oscillations over a large portion of the path, the resonant structure comprising a pair of grids spaced along said path and with both grids having a positive bias relative to said emitter means and said electrode, and wherein the device is free of beam focusing structure such that the beam of charged particles moving along the path is unfocused, the dimensions of the emitter means being such as to provide a beam having a substantial cross-sectional dimension and the spacing between the electrode and the emitter means being such as to minimize beam spreading.

A device for generating RF energy from electromagnetic radiation comprising emitter means responsive to the electromagnetic radiation impinging upon the emitter means for producing a beam of charged particles, an electrode spaced from the emitter means, the emitter means and the electrode defining a path therebetween along which the charged particles move, the charged particles moving along said path primarily as a result of the kinetic energy imparted to the charged particles by the electromagnetic radiation that produces the charged particles, and a resonant structure disposed between the emitter means and the electrode for supporting RF oscillations, the resonant structure being located with respect to the beam of charged particles to enable energy transfer from charged particles to an RF field associated with the RF oscillations, said device being free of externally applied voltages.

A device for generating RF energy from electromagnetic radiation comprising emitter means responsive to the electromagnetic radiation for producing a beam of low energy charged particles, a reflector electrode spaced from the emitter means, the emitter means and the electrode defining a path therebetween along which the charged particles move, a resonant structure for supporting RF oscillations disposed between the emitter means and the electrode and positioned with respect to the path to enable energy transfer between charged particles and an RF field associated with the RF oscillations, the resonant structure comprising a pair of grids spaced along said path and with both grids having a positive bias relative to said emitter means and said electrode, said bias being set to cause charged particles to remain substantially in phase with the RF field as they move along the path to continually transfer energy thereto.

A method of generating RF energy from electromagnetic radiation comprising producing from the electromagnetic radiation an unfocused beam of low energy charged particles that move along a predetermined path, locating the path in an RF field associated with RF oscillations in a resonant structure, the resonant structure comprising a pair of grids spaced along said path and with both grids having a positive bias relative to said emitter means and said electrode, and such that the path is substantially entirely without the RF field to enable continuous energy transfer to the RF field from the charged particles as they move along the path.