Abstract:
The invention relates to an ion source.This source comprises a gas ionization chamber, an electron source and means for oscillating the electrons in the chamber, so as to produce an ionization zone of the gas. The means for oscillating the electrons comprise two identical electron lenses, whose axes coincide with the oscillation direction, two spherical concave mirrors turned towards one another and positioned respectively on either side of the two lenses and whose centers respectively coincide with the foci of the lenses, the electron source being positioned at the focus of one of the two lenses.Application to the analysis of gases by mass spectrometry.
Abstract:
A thin freestanding oil film is produced in vacuum by directing an oil stream radially inward to the hollow-ground sharp outer edge of a rotating disc. The sides of the edge are roughened somewhat to aid in dispersing oil from the disc. Oil is removed from the surface of disc to prevent formation of oil droplets which might spin off the disc and disrupt the oil film. An ion beam is directed through the thin oil film so that electrons are stripped from the ions to increase their charge.
Abstract:
The present invention describes an ion gun which is capable of producing relatively high density ion currents. The ion gun employs at least one capillary duct the surface of which is semiconducting and has secondary electron emission coefficient greater than one to generate ions from a source of an ionizable material and to accelerate the ions so generated.
Abstract:
A source for generating singly and/or multiply charged ions composed essentially of a glow cathode, an intermediate electrode and an anode electrode having a common axis of symmetry and bordering a gas discharge chamber and each presenting a passage opening coaxial with the axis of symmetry, and a system producing a magnetic field having an axial component along the axis of symmetry, with the anode electrode opening being at a location where the magnitude of the axial component of the magnetic field is substantially equal to its maximum value.
Abstract:
A thin film of a low-thermionic-work-function material is maintained on the cathode of a device for producing a high-current, low-pressure gas discharge by means of sputter deposition from an auxiliary electrode. The auxiliary electrode includes a surface with a low-work-function material, such as thorium, uranium, plutonium or one of the rare earth elements, facing the cathode but at a disposition and electrical potential so as to extract ions from the gas discharge and sputter the low-work-function material onto the cathode. By continuously replenishing the cathode film, high thermionic emissions and ion plasmas can be realized and maintained over extended operating periods.
Abstract:
A cold-cathode ion source includes a specially shaped hollow anode and specially shaped anode-cathode insulators to preclude the buildup of short-circuiting bridges of sputtered cathode material. When used with solid feed material, the source can also include an oven-anode having cavities for vaporizing the solid feed material and passages connecting the cavities to the bore of the anode. The geometry of the oven-anode provides an increasing temperature gradient from the cavities to the bore that minimizes condensation of vaporized feed material that could block the ports.
Abstract:
Method and systems for managing clear-down are provided. The method can include generating a clear-down trigger associated with an ion mobility spectrometer and operating the ion mobility spectrometer in fast clear-down mode in response to the clear-down trigger. Methods and systems can further provide that where the ion mobility spectrometer operates in fast-switching mode, the ion mobility spectrometer alternating a plurality of times between operation according to a positive ion mode and operation according to a negative ion mode, and further operating according to the positive ion mode for less than about 1 second before switching to the operation according to the negative ion mode, and operating according to the negative ion mode for less than about 1 second before switching to the operation according to the positive ion mode.
Abstract:
Die Erfindung betrifft eine Quelle zur Erzeugung von gepulsten Ionen- und Elektronenstrahlen. Mit ihr wird ein in seinem Strahlquerschnitt großflächiger Strom geladener Teilchen erzeugt. Die Vakuum-Bogenplasmaquelle wird durch eine den Gesamtstrom bestimmende Last, die aus der Parallelschaltung eines ohmschen Widerstands mit einem Kondensator besteht, zur sichern Zündung geführt. Diese Last ist an den Innenwiderstand des Pulsspannungsgenerators leistungsangepaßt. Die Dimensionierung der elektrischen Bauteile an den Elektroden unter Berücksichtigung vorgegebener Schranken ermöglicht einen in seinem Strahlquerschnitt homogenen Strom geladener Teilchen, der aus ein und demselben Ladungsteilchen bei gleichen Zündelektroden oder aus einem strukturierten Strom unterschiedlicher Teilchensorten bei unterschiedlichem Zündelektrodenmaterial besteht.
Abstract:
There is disclosed a high speed pulse train generator for generating a train of pulses having arbitrarily close spacing. The apparatus in one form consists of a generator loop (82), comprising a fiber optic waveguide looped through a directional coupler (86), with the output fiber (76) serving as the input fiber for a similarly structured multiplexer loop (84). The lengths of the two loops (82, 84) are adjusted such that the time difference (τ) in the propagation times of light around the respective loops (82, 84) is small compared to the time of propagation around either loop (T, T- T ). The times are adjusted to obtain any arbitrary spacing of the pulses in the output pulse train (A. B. C, D, E) which comprises interleaved pulse trains resulting from each pulse input (92, 100) to the multiplexer loop (84). Also disclosed is a single loop embodiment for bidirectional data rate transformation and methods of using all the embodiments.