Abstract: A conventional stud-welding gun has been modified to allow it to be used for welding under water. The stud is contained within a water-tight enclosure formed at the end of the gun by pressing the seal at the end against the object to which the stud is to be welded. A water pump evacuates the enclosure and a stream of inert gas is provided to expel water and dry the region where the weld is to occur.

Abstract: One or more lasers direct one or more beams of radiant energy upon a nonlinear crystal having a sequence of rotational twin planes parallel to each other and perpendicular to the incident beams to produce an output beam at predetermined frequency at relatively high power level that may be detected or used in a suitable utilization device. Preferably the twin planes in the crystal are separated from each other by uniform spacing related to the coherence length for the nonlinear process being employed so that the power enhancement is proportional to the number of twin planes squared.

Abstract: A non-volatile charge storage element wherein long-term charge storage occurs in the interface states of the element. Charge is stored at low applied voltages (.ltoreq. 10 volts) in short times (.ltoreq. 1 microseconds) and is stored as long as 10.sup.5 seconds or longer. The states are emptied by exposure to radiation in the visible or the near infrared regions of the spectrum. There are described, also, an information storage device employing a plurality of such elements and a solid-state camera wherein the image screen includes a plurality of such elements. Changes in the charge storage in each of the elements results in changes in the capacitance of the element; either the capacitance of the element or its charge state is sensed to indicate the state of the element for information storage purposes. In one embodiment, thin film techniques are employed and a change in transconductance is detected to sense the charge state.

Abstract: A linear amplifier that is able to yield a maximum output voltage substantially greater than the breakdown voltage of the individual amplifying elements used and substantially greater than the voltage of a primary electric energy source that powers the amplifier. The amplifier consists of a plurality of stages connected in cascade, each stage, in turn, controlling the voltage level at which subsequent stages operate.

Abstract: Schemes for generating tunable coherent radiation by light mixing wherein input light radiation from one or more lasers is mixed in a nonlinear solid or a gaseous medium by using folded noncollinear geometry.

Abstract: A process wherein an aqueous solution containing dissolved phosphorus is seeded with iron oxide and a clay additive, if necessary, and with the electrolyte cation Al.sup.+.sup.3, the latter acting to associate the dissolved phosphate with the iron oxide and clay to form a coagulum. The coagulum is then removed from the solution magnetically.

Abstract: A way to determine, nondestructively, the purity or composition of an unknown material sample such as, for example, a sample of gold or silver of unknown purity. The procedure involves subjecting one end of an elongate sample of known length and weight to a temperature elevated relative to that of the sample and comparing the time-varying temperature pattern at the other end thereof during finite lengths of time with that of a known or identically-sized standard subjected to equivalent or the same conditions for an interval of time of the same finite length. The temperature of said other end can be monitored during the time heat is applied and/or after it is withdrawn.

Abstract: A spark plug wherein corona discharge is employed to create a long arc and to determine, in part, the path of the arc, electrodes of the spark plug being shaped, oriented and positioned to create an arc of desired length and at a desired location as well as to effect electromagnetic interaction between electric current in the arc and the electrodes to provide a force on the arc which acts to control its spatial behavior. The spark plug includes means to enhance the electromagnetic interaction.

Abstract: An electrical voltage is connected between a flexible soft-X-ray mask and a substrate causing the mask to make intimate contact and thereby conform to slight irregularities of the surface of the X-ray sensitive polymer on the substrate to minimize the effect of these irregularities during exposure to soft-X-rays.

Abstract: An electric power supply wherein electric energy is processed using high frequency techniques to provide as output electric energy whose frequency and/or voltage are programmable. The apparatus described can, for example, accept as input low frequency energy (e.g., 60 Hz) at available voltages (e.g., 120/240/480) and can process the same through intermediate high frequency steps to provide an output at power levels and voltages found in industrial power circuits, that can be varied both in frequency and voltage; or the input can be processed in like manner to give, for example, a very high voltage pulsed output.

Abstract: An auditorium simulator which is suitable for earphones or speakers placed closely to the ears, is comprised of delay and attenuation devices for simulating the various sound paths in an auditorium and includes listener simulating means for producing different direction-signifying transforms to the signals for the two ears, thus to give cues to the ears for localizing the direction of the signals in the respective simulated sound paths. Use of a number of these paths synthesizes the various important reflected images of the sound source, even of wide stage images, making possible a realistic high fidelity impression of concert hall attendance. Conventional two channel stereo recordings played from a conventional player or receiver are processed by an adapter for use by the simulator. The listener transforms are based upon interaural time delay between the ears of a listener, head shadow for the ear remote from the wall from which a reflection is supposed to be received and pinna effect.

Abstract: A cathode ray tube (CRT) having a faceplate-deposited cathodochromic material, said CRT having electron beam write and erase. The erase beam is an electron beam focused to a size of approximately 0.010 inches at the image screen of the CRT and the intensity of the beam is about 10.sup.5 watts/in.sup.2.

Abstract: A process for electrically interconnecting a group of integrated-circuit chips embedded in plastic is described. Multilayer conductors are plated in grooves photoformed in successively applied plastic layers and connected to the chip pads and to conductors on other layers through vias also photoformed in the plastic. Photoformation of wiring grooves and layer-interconnecting vias is accomplished by ultraviolet irradiation of photosensitized liquid polyester resin.

Abstract: An electrical insulator composed of one or more electrical insulating skirts or sheds or shells at least some of which skirts or sheds or shells have a plurality of discrete conductive regions at one surface thereof, the discrete conductive regions being appropriately arranged and sufficient in number to intercept an arc in the event of incipient flashover from proceeding radially past the discrete conductive regions, thereby to prevent said flashover.

Abstract: A cathode-ray tube projection system employing a cathodochromic image screen and electron beam erase and in which the image is projected from the image screen surface nearest the electron gun. The main advantages of this system are higher resolution and improved image erasure which provides a high-contrast image.

Abstract: A superconducting machine wherein the field winding and associated elements in the cold region of the machine are protected against transients by a flexible, electrically conductive outer shield means that interacts with an inner conductive shell in a way that causes the magnetic field to be compressed between the shield and the shell, thereby to transmit mechanical radial forces between the two.

Abstract: A field effect semiconductor device that has particular use in limiting current in electric circuits over a very wide power range. In a preferred form, the device consists of a crystalline-material semiconductor wafer having multiple channels at one major surface thereof, the channels being separated by grooves formed along parallel crystallographic planes of the crystalline material. The wafer material forming each of the channels is lightly doped and each channel is bounded by flat walls, parallel to one another and formed by highly doping the wafer material with a dopant that is opposite in type to that of the channels. All said one major surface of the wafer is highly doped with the opposite-type dopant to that of the channels with the exception of ohmic-electric-contact regions of each channel, which regions are highly doped with the same-type dopant as that of the channels. All said one surface, except at the edge or edges thereof, is covered by a first conductive terminal.

Abstract: A long exposure photometer-digitizer operative in an integration mode to receive weak illumination as from celestial observations through a telescope or from field or laboratory observations of objects and to provide a recorded digital representation thereof. A silicon, vidicon illumination sensor is employed to provide a wide dynamic range, sensitive and linear response over a large spectral region. Cumulative photon interaction with the vidicon tube during a long exposure is achieved by operating the vidicon at a reduced temperature which minimizes dark current effects and promotes integration mode operation. After a predetermined vidicon exposure interval the image electrically stored in the target is read out by a scanning electron beam, digitized and recorded to provide an immediately available digital record of the object. The target is sensitized before each exposure.

Abstract: This invention provides a composite composition comprising a metallic matrix having a concentration of third phase solid particles homogeneously dispersed throughout the metallic matrix. The metallic matrix can be liquid, solid or partially solid and can have (a) a dendritic structure or (b) up to 65 weight percent of a structure comprising degenerate dendritic or nodular primary discrete solid particles suspended in a secondary phase having a lower melting point than the primary particles which secondary phase can be solid or liquid. The third phase particles can be metallic, non-metallic or a combination metallic-nonmetallic compositions and have a surface composition which is not wet by the metallic matrix when the matrix is a liquid.

Abstract: Low frequency noise in a gas laser is suppressed by providing an auxiliary cathode in proximity to the anode to provide an auxiliary gas discharge between these elements. The anode and another cathode provide a primary gas discharge for lasing operation.