Abstract:
A laser sustained plasma light source having a cell with a gas volume contained within the cell. At least one laser is directed into the gas volume, for sustaining a plasma within the gas volume, which plasma produces a light. Means are provided for continuously providing the gas volume to the plasma in a laminar flow. A reflector collects the light and provides the light to a desired location.
Abstract:
A device for thermal monitoring a piece of equipment, which is integrated on a craft placed in a forced vacuum environment, an outside part of the equipment projecting outside of a wall of the craft and being subjected to a solar radiation flux, includes an absorbent screen that is suitable for being placed between the outside part of the equipment and the wall of the craft, whereby this absorbent screen has—on at least one portion of its front face, designed to be placed on the side removed from the wall of the craft—an absorptivity αSOLAR that is the largest possible in the field of solar radiation, coupled to a low emissivity εIR in the infrared spectrum. The absorbent screen is made of a very heat-conductive material and has—on at least a portion of its rear face, suitable for being oriented toward the wall of the craft—a high emissivity εIR in the infrared spectrum, typically greater than or equal to 0.7.
Abstract:
A collector sweeping method for controlling an electron beam in a beam collector, in particular of a magnetic gyrotron device, comprises the steps of subjecting the electron beam to a transversal sweeping field having a field component perpendicular to a longitudinal direction (z) of the beam collector and providing a tilted, rotating intersection area of the electron beam in the beam collector, and varying at least one of a longitudinal position and a tilting angle of the intersection area by a modulation of the transversal sweeping field. Furthermore, a collector sweeping apparatus and a microwave generator are described.
Abstract:
A collector structure for a linear bean device is disclosed having a segmented ceramic collector core that permits sustained operation at high temperatures and high power densities, such as encountered in miniature traveling wave tubes. More particularly, the collector assembly provides efficient heat transfer from the collector core at elevated temperatures while reducing stresses on collector components caused by thermal cycling. The collector assembly comprises a heat sink having a cylindrical cavity providing interior vacuum walls for the assembly, a segmented annular ceramic insulator disposed inside the cylindrical cavity, and an electrode disposed inside and against the ceramic insulator. The ceramic insulator comprises separate sectors separated from one another by gaps, and may be notched in its outer surface for high-voltage stand-off from the heat sink. The electrode is preferably not brazed or soldered to the ceramic insulator. A second stage of the electrode may be probeless and may comprise a central conical depression having a aspect ratio greater than one. In an embodiment of the invention, the heat sink and second stage electrode of the collector assembly are both made of molybdenum, and the ceramic insulator is made of beryllium oxide, aluminum nitride, or alumina. In an alternative embodiment, the heat sink and the second stage electrode are both made of copper, and the ceramic insulator is an aluminum nitride material.
Abstract:
An electron-beam tube with an electron collector for an electron-beam entering the electron collector in an electron-beam direction. A plurality of large-area projections are provided for heat radiation including a funnel-shaped projection expanding in the electron-beam direction. The funnel-shaped projection includes a smaller opening which is one of directly and indirectly fastened to the collector and including an upstream projection including a surface which is first with respect to the electron-beam direction, the surface facing the arriving electron-beam and the surface being provided with low heat radiation properties. All other surfaces of the plurality of projections having high heat radiation properties higher than the low heat radiation properties. The collector and the plurality of projections being supported by a satellite as a travelling-wave tube with the electron collector radiating into space.
Abstract:
The method according to the invention comprises winding a metal wire substantially helically both round a fitting constituted by a flexible strip and around two rods arranged parallel to the fitting axis and on either side of the fitting. The rods are eliminated when the metal wire is wound. The fitting comprises means limiting the displacement of the wire in accordance with the fitting axis, which coincides with the axis of the helix according to which the wire is found. These means are constituted by two rows of slots made in the lengthwise direction on two opposite edges of the strip constituting the fitting.