Abstract: A collapsible garment hanger including a hook element attached to a fixed arm, a sliding arm with a longitudinally oriented slot, a crosspiece extending through the slot, attaching the sliding arm slidably to the fixed arm. When the distal end of the fixed arm tilts upward, gravity will cause the sliding arm to slide away from the distal end of the fixed arm. Whenever the distal end of the fixed arm tilts downward, gravity will cause the sliding arm to slide towards the distal end of the fixed arm. The collapsible garment hanger can also manually slide away from or towards the distal end of the fixed arm. An offset spacing between the outer tip of the sliding arm when it is in the collapsed position and the opposing offset portion of the hanger determines the size of neck of garment through which the hanger will fit.

Abstract: A steerable antenna comprising an array of T-shaped slots. The location of the slots is moved to define an array of ring- or spiral-patterned phase constant regions. Distortions or contractions of the pattern occur by repositioning some or all of the slots forming the array. The antenna also comprises an intermediate insulating layer and a lower plate. The insulating layer is formed by a deformable dielectric medium. Deformation of the dielectric medium allows the beam angle to be altered.

Abstract: An array of dielectric wave antennas is disclosed. Each wave antenna has a central dielectric portion and two dielectric tapered portions, disposed on opposite sides of the central dielectric portion. The array is deployed in a lens shape and allows variation of the phase delay of an incident electromagnetic wave when passing through the array.

Abstract: The present invention relates to a method for making an achromatic lens. The invention provides a method for making a lens that makes use of the differences in the index of refraction of ZnSe and ZnS in the mm-wave and IR wavebands to minimize the differences in focal position between the two wavebands. A lens train thus made can be used in conjunction with a dual-band focal plane array to simultaneously focus two wavebands on a common focal plane and thus provide for simultaneous imaging in both wavebands.

Abstract: An array of dielectric wave antennas is disclosed. Each wave antenna has a central dielectric portion and two dielectric tapered portions, disposed on opposite sides of the central dielectric portion. The array is deployed in a lens shape and allows variation of the phase delay of an incident electromagnetic wave when passing through the array.

Abstract: The present invention relates to a method for making an achromatic lens. The invention provides a method for making a lens that makes use of the differences in the index of refraction of ZnSe and ZnS in the mm-wave and IR wavebands to minimize the differences in focal position between the two wavebands. A lens train thus made can be used in conjunction with a dual-band focal plane array to simultaneously focus two wavebands on a common focal plane and thus provide for simultaneous imaging in both wavebands.

Abstract: The present invention relates to a method for designing an achromatic lens and a lens according to the design. The invention provides a lens that makes use of the differences in the index of refraction of ZnSe and ZnS in the mm-wave and IR wavebands to minimize the differences in focal position between the two wavebands. This lens train can be used in conjunction with a dual-band focal plane array to simultaneously focus two wavebands on a common focal plane and thus provide for simultaneous imaging in both wavebands.

Abstract: Dual band millimeter-wave and infrared anti-reflecting coatings are presented, which enhance the passage of millimeter-wave and infrared radiation into a substrate material. A substrate is coated with a quarter-wave coating of an infrared anti-reflecting material followed by a quarter-wave coating of a millimeter-wave anti-reflecting material followed by a second quarter-wave coating of an infrared anti-reflecting material. The second infrared anti-reflecting coating enables incident infrared radiation to pass into the millimeter-wave anti-reflecting material, while minimizing reflection. The first infrared anti-reflecting coating enables incident infrared radiation from the millimeter-wave anti-reflecting material to pass into the substrate material, while minimizing reflection. The millimeter-wave anti-reflecting coating enables incident millimeter-wave radiation to pass into the substrate material, while minimizing reflection.

Abstract: A high impedance (Hi-Z) wire effectively transparent to electromagnetic radiation polarized in the direction of the wire, within an operating frequency band. The Hi-Z wire is sheathed with a thin layer of resonant structures that are small compared to the wavelength, and behave as a kind of photonic band gap (PBG) material. A frequency-selective polarizer comprising a plurality of Hi-Z wires disposed parallel to one other in a grid. A wire grid reflector that enables stepwise phase control of the reflected wave and focusing of radiative power, the reflector comprising Hi-Z wires interspersed with conventional wires disposed parallel to one another in a grid.

Abstract: A tuneable impedance surface for steering and/or focusing a radio frequency beam. The tunable surface comprises a ground plane; a plurality of elements disposed a distance from the ground plane, the distance being less than a wavelength of the radio frequency beam; and a capacitor arrangement for controllably varying the capacitance of at least selected ones of adjacent elements. A method of tuning the high impedance surface allows the surface to mimic, for example, a parabolic reflector or a diffraction grating.

Abstract: A method and apparatus for providing a high impedance structure or surface comprising at least one electrically conductive wire forming at least one elongate wire spiral, the at least one elongate wire spiral being defined by a plurality of spirals of said at least one wire, the spirals having a pitch and being spaced apart along a major axis of said elongate wire spiral; and an arrangement for varying the pitch of the spirals of said at least one wire to thereby tune the impedance of said tuneable impedance structure. An embodiment useful as an antenna aperture to steer a radio frequency beam having two different polarizations is disclosed.

Abstract: Improved magnetron oscillators that controllably form a plasma within each of its resonant cavities to rapidly change the resonant frequency of each cavity. The present invention also provides for frequency tuning methods for use with magnetron oscillators. The plasma is controllably formed in one or more subcells of each resonant cavity in a manner that alters the electromagnetic field within each cavity. Preferably, a magnetized collisional plasma is controlled to rapidly change the resonant frequency of each cavity. However, many types of plasmas may be used to implement the present invention. Controlling formation of the plasma within each cavity tunes the magnetron oscillator on a submillisecond time scale.

Abstract: A pollutant destruction system connects a capacitive corona discharge chamber in a self-resonant circuit with an inductive element. Intermittent energizing signals are furnished from a power supply to induce corona discharges within the chamber, with the resonant circuit responding to the energizing signals by initiating additional corona discharges between energizing signals in a highly energy efficient operation. One or more discharge chambers can be provided in the resonant circuit, with each discharge chamber comprising a dielectric enclosure with a distributed electrode outside and an elongate electrode inside the enclosure. The inner electrode can extend either along the chamber axis, or along the inner chamber wall for better support and heat dissipation.

Abstract: A pollutant destruction system connects a capacitive corona discharge chamber in a self-resonant circuit with an inductive element. Intermittent energizing signals are furnished from a power supply to induce corona discharges within the chamber, with the resonant circuit responding to the energizing signals by initiating additional corona discharges between energizing signals in a highly energy efficient operation. One or more discharge chambers can be provided in the resonant circuit, with each discharge chamber comprising a dielectric enclosure with a distributed electrode outside and an elongate electrode inside the enclosure. The inner electrode can extend either along the chamber axis, or along the inner chamber wall for better support and heat dissipation.

Abstract: A method of operating a flywheel (10) includes the provision of a central shaft (12) defining an axis of rotation; providing a disk-shaped hub (22) joining drivingly with both the shaft and with a rim portion (34); and which hub portion has a shape when the flywheel is at rest which is of a shallow dihedral geometry. That is, the hub is cone-shaped when the flywheel is at rest. As the rotational speed of the flywheel is increased from the at-rest speed toward and then to a design operating speed for the flywheel, this hub progressively flattens out until it becomes flat and extends radially between the shaft and the hub at the design speed for the flywheel. Thus, the flattening of the hub with increasing rotational speed for the flywheel moves the rim portion axially in response to centrifugal force.

Abstract: A pollutant destruction system connects a capacitive corona discharge chamber in a self-resonant circuit with an inductive element. Intermittent energizing signals are furnished from a power supply to induce corona discharges within the chamber, with the resonant circuit responding to the energizing signals by initiating additional corona discharges between energizing signals in a highly energy efficient operation. One or more discharge chambers can be provided in the resonant circuit, with each discharge chamber comprising a dielectric enclosure with a distributed electrode outside and an elongate electrode inside the enclosure. The inner electrode can extend either along the chamber axis, or along the inner chamber wall for better support and heat dissipation.

Abstract: A corona source suitable for use in vehicle ignition systems uses a conductive coil that receives an RF input at one end and has a corona discharge site at the other end, with a reference electrode capacitively coupled to the coil. The pitch and the length of the coil are selected to produce a corona discharge in response to an RF input signal at a predetermined frequency and voltage, through quarter wavelength resonation. Either the new resonant coil or other corona discharge devices can be used to remediate fluid-borne wastes by initiating and sustaining RF corona discharges within the fluid. The pulses used to initiate the corona discharge preferably have alternating positive and negative components, with high initial voltages on the positive components to initiate the discharge, followed by lower positive voltage levels to sustain the discharge. Unipolar pulses, preferably with progressively decreasing voltage levels, can also be used.

Abstract: A corona source suitable for use in vehicle ignition systems uses a conductive coil that receives an RF input at one end and has a corona discharge site at the other end, with a reference electrode capacitively coupled to the coil. The pitch and the length of the coil are selected to produce a corona discharge in response to an RF input signal at a predetermined frequency and voltage, through quarter wavelength resonation. Either the new resonant coil or other corona discharge devices can be used to remediate fluid-borne wastes by initiating and sustaining RF corona discharges within the fluid. The pulses used to initiate the corona discharge preferably have alternating positive and negative components, with high initial voltages on the positive components to initiate the discharge, followed by lower positive voltage levels to sustain the discharge. Unipolar pulses, preferably with progressively decreasing voltage levels, can also be used.

Abstract: A corona source suitable for use in vehicle ignition systems uses a conductive coil that receives an RF input at one end and has a corona discharge site at the other end, with a reference electrode capacitively coupled to the coil. The pitch and the length of the coil are selected to produce a corona discharge in response to an RF input signal at a predetermined frequency and voltage, through quarter wavelength resonation. Either the new resonant coil or other corona discharge devices can be used to remediate fluid-borne wastes by initiating and sustaining RF corona discharges within the fluid. The pulses used to initiate the corona discharge preferably have alternating positive and negative components, with high initial voltages on the positive components to initiate the discharge, followed by lower positive voltage levels to sustain the discharge. Unipolar pulses, preferably with progressively decreasing voltage levels, can also be used.

Abstract: A waveguide filter (22,24) is incorporated into a cavity resonator (20) for a free-electron laser or the like by coating a material layer (24) on the inner peripheral surface of a hollow waveguide member (22). A high pass filter configuration is provided when the conductivity of the material layer (24) is higher than that of the waveguide member (22), such that electromagnetic signals having wavelengths longer than the skin depth of the material layer (24) pass into and are affected by the lower conductivity waveguide member (22). Reversing the conductivities produces a low pass filter configuration in which signals having wavelengths shorter than the skin depth are affected by the material layer (24). A bandpass filter configuration is provided by adding an additional material layer (32) of low conductivity to a high pass filter, whereas a band exclusion filter configuration is produced by adding an additional material layer (32) of high conductivity to a low pass filter.