Abstract: Field emission devices utilizing capacitive ballasting are described with possible uses in industry. The preferred device utilizes opposing electrodes, each with a dielectric layer and a plurality of conductive islands which serve to exchange electrons, generating an oscillatory current. Ideally these islands are dome-shaped and made of a refractory metal such as tungsten of molybdenum. Through proper use and selection of materials, electrical fields with densities of 1014 A/m2 are capable of being generated.

Abstract: A method of non-invasive determination of electrical current distribution is disclosed. The method utilizes mathematical calculations on data obtained by a probe with non-uniformly wound detection coil. While non-uniform, the coil winding is specific according to a known and determined function, such as a sinusoidal variation. As a further method, the probe may rotate about an area of interest and the data then may be subjected to a Fourier analysis for further refined results. Multiple coils may be used in the probe, each with a different coil function which could include one uniform coil. Also disclosed is a method for making the coils necessary in the practice of the method.

Abstract: A method of non-invasive determination of electrical current distribution is disclosed. The method utilizes mathematical calculations on data obtained by a probe with non-uniformly wound detection coil. While non-uniform, the coil winding is specific according to a known and determined function, such as a sinusoidal variation. As a further method, the probe may rotate about an area of interest and the data then may be subjected to a Fourier analysis for further refined results. Multiple coils may be used in the probe, each with a different coil function which could include one uniform coil. Also disclosed is a method for making the coils necessary in the practice of the method.

Abstract: An improved device, method, and system efficiently couple high-frequency energy from radiation-assisted field emission. A radiation source radiates an emitting surface with an electromagnetic field. The electromagnetic field reduces the potential barrier at the emitting surface, allowing electrons to tunnel from the surface. The tunneling electrons produce a current. The electron tunneling current oscillates in response to the oscillations of the electromagnetic field radiation. Two or more electromagnetic fields of different frequencies radiate the emitting surface, causing photomixing. The electron tunneling current oscillates in response to the difference of the frequencies of the electromagnetic fields.

Abstract: A source electrode is biased to lower the potential barrier of surface electrons. A laser radiates the source electrode, producing a tunneling electron current. The tunneling electron current oscillates in response to frequency of the laser. The impedance match circuit couples the current from a high-impedance source electrode of a laser-assisted field emission to a lower-impedance connector, creating a high-frequency microwave signal source. Two or more lasers may be photomixed to further tune the frequency of the microwave signal.

Abstract: An improved device, method, and system efficiently couple high-frequency energy from radiation-assisted field emission. A radiation source radiates an emitting surface with an electromagnetic field. The electromagnetic field reduces the potential barrier at the emitting surface, allowing electrons to tunnel from the surface. The tunneling electrons produce a current. The electron tunneling current oscillates in response to the oscillations of the electromagnetic field radiation. Two or more electromagnetic fields of different frequencies radiate the emitting surface, causing photomixing. The electron tunneling current oscillates in response to the difference of the frequencies of the electromagnetic fields.

Abstract: An apparatus for measuring high frequency currents includes a non-ferrous core current probe that is coupled to a wide-band transimpedance amplifier. The current probe has a secondary winding with a winding resistance that is substantially smaller than the reactance of the winding. The sensitivity of the current probe is substantially flat over a wide band of frequencies. The apparatus is particularly useful for measuring exposure of humans to radio frequency currents.

Abstract: An apparatus for high speed gating of electric current based on the resonant interaction of tunneling electrons with optical fields is disclosed. The present invention biases an electron-emitting tip with a DC voltage source and focuses an output from a laser on the electron-emitting tip to stimulate electron emission from the tip. The electron emission creates an electrical signal that is coupled to circuitry for further processing. In accordance with the present invention, various methods of coupling the electrical signal from the electron-emitting tip are disclosed, as are various methods of reducing the magnitude of the laser output needed to stimulate electron emission, and methods of enhancing the static current density.

Abstract: A catheter is used to insert a probe into a tumor undergoing hyperthermia treatment. The probe is designed to isotropically measure the electric field and temperature in the tumor during the hyperthermia treatment. The probe is constructed on a triangular prism and includes a dipole on each prism face oriented at an angle of 54.74 degrees relative to the axis of the prism. Each dipole includes rectifier means therein and the three dipoles are coupled serially using high resistivity lead means. In addition, high resistivity leads are used to couple the dipoles to a high input impedance amplifier. A pair of thermistors are coupled between the three dipoles, and high resistance lead means couple the thermistors to high input impedance amplifiers. A current source is used to provide current to the thermistors in a time shared manner when the electric field is not being measured.

Abstract: A current detector for detecting the high frequency current flowing in a conductor includes a coil of high resistivity material wound around an non-ferromagnetic core. The coil is arranged in a substantially closed loop configuration around the conductor carrying the current to be measured. The ratio of the winding spacing to the cross sectional area of the coil is maintained constant over the length of the winding. A shield of high resistivity material surrounds the coil and is spaced from the coils and the shield has a gap oriented along an azimuth of the closed loop winding and directed orthogonal to the net current direction of the current induced in the coil. The ends of the coil are coupled to a high impedance voltage detector through high resistivity leads and a relatively low value resistor is coupled between the leads to reduce the quality factor.

Abstract: A current detector for detecting the high frequency current flowing in a conductor includes a coil of high resistivity material wound around an non-ferromagnetic core. The coil is arranged in a substantially closed loop configuration around the conductor carrying the current to be measured. The ratio of the winding spacing to the cross sectional area of the coil is maintained constant over the length of the winding. A shield of high resistivity material surrounds the coil and is spaced from the coils and the shield has a gap oriented along an azimuth of the closed loop winding and directed orthogonal to the net current direction of the current induced in the coil. The ends of the coil are coupled to a high impedance voltage detector through high resistivity leads and a relatively low value resistor is coupled between the leads to reduce the quality factor.