Abstract: An electrode of an inductive output tube (IOT) is provided with channels for guiding cooling fluid. In one aspect of the invention, the channels are in a confronting relationship with a jacket surrounding the electrode and spaced from the electrode so as to define an interior region. Cooling fluid such as oil is circulated in the channels in fluid communication with the interior region, providing an escape mechanism for trapped bubbles in order to prevent localized heating of the electrode. In another aspect of the invention, the channels form multiple intersecting helical patterns of different pitches, with the steeper-pitched channels providing a more direct escape route for the bubbles.

Abstract: A light modifier for an LED producing light about a central axis can reduce the appearance of a bright spot created by the LED. The light modifier comprises a lens defining an indentation at its outer surface, with the indentation having an angled side wall and an outer edge joining the side wall to the outer surface. The side wall is spaced from the LED and angled relative to the central axis such that light produced by the LED and striking the side wall is at least substantially internally reflected to pass through a light transmitting portion of the outer surface directly bordering the outer edge, forming a line of light around the indentation.

Abstract: A light modifier for an LED producing light about a central axis is provided. The light modifier includes a lens defining an indentation. The indentation is angled relative to the central axis by an amount less than a complementary angle of a critical angle of the lens along the indentation. The lens can reduce the appearance of a bright spot created by the LED.

Abstract: A light modifier for an LED producing light about a central axis is provided. The light modifier includes a lens defining an indentation. The indentation is angled relative to the central axis by an amount less than a complementary angle of a critical angle of the lens along the indentation. The lens can reduce the appearance of a bright spot created by the LED.

Abstract: An electrode structure for a vacuum tube is formed by having a ceramic insulating body act as the tube wall. Electrode areas are formed on the inside of the tube by coating the inside of the tube wall with a conductor. These electrode areas are then coupled, as necessary, to external electronic circuits. The coupling may be performed by through-wall connections, metallized abutting connections and other conventional means. The ceramic insulating body may be generally cylindrical in shape and may be formed of a material such as aluminum nitride, beryllium oxide, aluminum oxide and the like.

Abstract: The present invention provides an X-ray generating apparatus with a shield structure having an electron beam collimating aperture and heat transfer device. The shield structure is made of thermally conductive material and placed in the discharge space between an electron source and rotating anode target. The shield structure is formed by a concave top surface facing the electron source, a flat top surface facing the anode target, and inner and outer walls wherein a linear dimension of the inner wall is substantially smaller than the linear dimension of the outer wall. The inner wall surrounds the beam collecting aperture. The heat transfer device is placed in a beveled portion of the shield structure. The heat transfer device includes an extended coiled wire formed from thermally conductive material and conductively attached to the knurled interior of the shield structure to transfer heat to the cooling liquid passing through inflow and outflow chambers of the shield structure.

Abstract: An X-ray tube rotating anode is cooled with a liquid metal functioning as a recirculated heat exchange fluid and/or a metal film in a gap between the anode and a stationary structure. The liquid metal is confined to the gap by (a) a labyrinth having a coating that is not wetted by the liquid, (b) a magnetic structure, or (c) a wick. The liquid metal recirculated through the anode is cooled in a heat exchanger located either outside the tube or in the tube so it is surrounded by the anode. The heat exchanger in the tube includes a mass of metal in thermal contact with the recirculating liquid metal and including numerous passages for a cooling fluid, e.g. water. A high thermal conductivity path is provided between an anode region bombarded by electrons and a central region of the tube where heat is extracted.

Abstract: A heat sink element, preferably one formed with a relatively large surface area from which thermal energy can be transferred convectively and radiatively to an ambient atmosphere, with or without forced fluid flow, is held forcibly in contact with a heat transmitting surface of a heat source for thermal conduction of heat therefrom. A heat sink attachment element affixed to the heat sink element has flexibly attached castellated extensions formed with tapered end teeth contacting a correspondingly inclined surface of the heat source. The castellated extensions are each subjected to a continual externally applied force and the total resultant force thereof, holding the heat sink element to the heat source, thereby can be maintained or will increase as the assembly experiences thermal cycling and mechanical disturbances during use. The effectiveness of thermally conductive contact between the heat sink and heat source therefore does not deteriorate during prolonged use.

Abstract: A novel window assembly with improved cooling capabilities for use in high power microwave tube and waveguide apparatus is disclosed. A septum with a circular central aperture is disposed between two parallel windows. Cooling fluid is circulated in from the periphery of one of said windows, flows toward the central region, through the aperture in the septum, and then out at the periphery of the second of said windows. This arrangement results in an increased cooling fluid velocity thereby increasing the cooling effectiveness of the window assembly. By adding surface features such as bumps, channels and the like to the septum, one can additionally increase local cooling fluid velocity in areas of the window assembly subject to greater localized heating. This is particularly useful in gyrotron tubes, where the energy impinging on the window surface is in the circular-electric-field mode and areas of the window surface are known to be subject to greater thermal stress.

Abstract: A linear beam tube has multiple heat pipes formed integrally in the cavity wall between the beam collector and external air cooling fins. The heat pipes use sintered copper pellets on the walls of the pipes as wicks to facilitate the return flow of liquid condensed at the fins. Circumferential channels connect the heat pipes at each end to reduce vapor lock effects. Vapor surface area enhancement rods are used at the heat source to increase the transfer rates of heat into the fluid.

Abstract: A cylinder or barrel fitted with cams is used to limit the outward movement of spring-loaded plungers attached to cavity shorting bars in a klystron. Different tunings of the klystron are achieved by rotating the cylinder so that different rows of cams limit the plungers. A linear solenoid is used to decouple the plungers from the cams before rotation. A stepping solenoid is used to move the cylinder from one setting to another.

Abstract: A method of aiming or aligning in which two overlapping fields of view fixed with respect to each other are produced, one of which is inverted and reversed with respect to the other and superimposed thereon. Given a target in the overlapping fields of view, movement of the fields of view to cause a given point on the target in the two images thereof provided by the two fields of view to overlie each other will cause such points to lie on an axis having a fixed relation to the axes of two fields of view. Optical and electronic devices for practicing the method are described.

Abstract: A pressure release assembly provides controlled depressurization of a sea gas-containing vessel, such as a xenon-filled arc lamp, when the temperature of the gas in the vessel reaches a value corresponding to a selected pressure. The assembly comprises a thin metallic rupture plate that hermetically seals an aperture in a wall of the vessel, and a back-up disc that is supported adjacent the other surface of the rupture plate. The back-up disc reinforces the rupture plate so as to prevent bursting of the rupture plate at pressures below the selected pressure. The back-up disc is made of a material that loses its tensile strength at the temperature corresponding to the selected pressure, whereby the weakening of the back-up disc at the selected pressure causes the rupture plate to burst. The back-up plate may be made of a eutectic alloy that melts at the temperature corresponding to the selected pressure.

Abstract: The heat-transfer capability of a movable-electrode gas-filled arc lamp is optimized. In the preferred embodiment, the movable electrode is the anode which is mounted at the base of the lamp coaxialy with and spaced apart from the cathode. Low-voltage starting of the lamp is provided by solenoid means for moving the anode briefly into contact with the cathode and then withdrawing the anode from contact with the cathode so that a difference of electrical potential develops between the cathode and the anode, which is sufficient to ionize the gas in the gap formed therebetween. The arc thereby generated in the gap follows the withdrawing anode to its fully spaced-apart position with respect to the cathode. A heat sink member is disposed within the gas-filled envelope at the base of the lamp, and a metal collar is affixed to and surrounds the movable anode. The collar provides thermally conductive contact with the heat sink member when the anode is in its fully spaced-apart position with respect to the cathode.