摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
An FEL array is comprised of adjacent FEL modules. Each module preferably uses a ribbon beam plasma-anode E-gun (PAG) or another plasma-assisted E-gun to produce a planar E-beam that interacts with a planar wiggler magnetic field. The modules may share a common electron gun. A control signal is input through a phase priming array to preselect the radiation mode. A planar, distributed Bragg resonator/reflector is used to set up a high-Q cavity, enabling the low gain module to produce high power radiation. The FEL modules are arranged in an array to reduce the output radiation flux density while achieving high output power density in the far-field, and to permit beam steering by phase control of individual modules. The relatively low current density of the individual E-guns lessens the size of the guiding magnetic field in each module to the extent that the wiggler magnetic field alone is sufficient to perform this guiding function.
摘要:
A method of optimizing the design of waveguide reflector surfaces for high-Q cavities. The method assumes ideal conducting surfaces and proceeds from simple planar waveguide systems which are compatible with resonant standing waves to the development of the allowable surfaces which are necessary to contain the standing waves in a finite system. Apparatus constructed in accordance with the method achieves a Q in excess of 10,000.
摘要:
A plasma-anode electron gun includes a cathode means of a material such as molybdenum having a relatively high ratio of emission of secondary electrons to impinging helium ions. A hollow annular anode structure (16) contains an ionized plasma, and has a central opening (38) through which the electron beam (36) is directed, when ions from the anode are released to impinge upon the cathode (12). The anode and ion source structure may be grounded, and ions are released through openings facing the cathode when a positive trigger pulse is applied to one or more electrodes extending within the plasma. The cathode is preferably operated at a voltage in the order of thirty to two hundred thousand volts negative with respect to the cathode. Leakage of ions from the hollow anode may be inhibited by the provision of a supplemental grid biased to a low positive potential.
摘要:
A crossed-field switch device is connected in parallel to a load device which may arc. The characteristics of the crossed-field switch device are that it will not conduct when a high voltage is applied, but when the load device arcs, the crossed-field switch device conducts, taking current from the arc so that the arc quenches. The crossed-field switch device thus is a crowbar which is automatically conductive when the applied voltage decreases due to a line or load short.