Abstract:
This disclosure is concerned with a process of and apparatus for producing relatively low energy electron beams through pulsed cold-cathode beam generation in a mode of operation involving an important intermediate region of a substantially linear depth-dose profile characteristic that reduces the sensitivity to possible voltage variations, and with improved triggering structures that significantly improve reliability and minimize erratic pulse generation and missing pulses, thus particularly adapting the process and apparatus for such stringent applications as production-line sterilization of surfaces, materials or workpieces passed by the apparatus.
Abstract:
The method for controlling the migration of an electronegative chemical species within a solid substrate which exhibits ionic conduction consists in irradiating the substrate with electrons which have sufficient energy to penetrate into the substrate and to produce therein metastable excited negative ions of said species and in applying to said substrate an electric field having a direction opposite to the desired direction of migration.
Abstract:
A power supply for the cathode of an electron beam gun disposed in a vacuum chamber comprises a transformer for frequencies above about 20 kHz and having a primary winding and a secondary winding connected to the cathode. The transformer is mounted so as to integrate same into the vacuum chamber to dispose the primary winding in communication with the atmosphere and the secondary winding in communication with the vacuum chamber. A partition is disposed between the primary winding and the secondary winding to seal the primary winding from the vacuum and the seondary winding from the atmosphere. A control circuit receptive of a direct current supply has the output thereof connected to the primary winding of the transformer and has pulse width controlled transistors for the chopping of the direct current at a frequency above about 20 kHz.
Abstract:
System for the power control of high voltage electron beam generators having a cathode and a control electrode associated with the cathode. The system is provided with a high voltage isolation transformer with primary and secondary winding for supplying the control electrode with a control voltage. A system precedes the isolation transformer on the primary side and is adapted to generate square wave pulses susceptible of amplitude modulation. The pulse generator is designed such that the pulses are square wave impulses symmetrical with the null line. The isolation transformer is provided with a tertiary winding on the primary side and the primary winding receives input from an amplifier whose input is connected with the output voltage of the tertiary winding. A rectifier bridge is connected to the secondary winding.
Abstract:
An electron gun for heating, fusing and vaporizing having a high voltage portion, an electron emitting cathode and at least one beam forming electrode associated with the cathode. An accelerating anode, a beam guiding tube extending in the direction of the beam path and surrounded by a jacket tube and an electromatic lens are also provided. One or more deflection systems are positioned in the space formed between the beam guiding tube and the jacket tube. The beam guiding tube, the jacket tube, the electromatic lens and the deflection systems are contained in a single, replaceable unit which is joined by a plurality of hollow posts parallel to the gun axis to the high-voltage portion of the gun. The space for the electromagnetic lens and the deflection systems communicates with the atmosphere through at least one of the hollow posts.
Abstract:
In a sample analysis apparatus, a sample to be analyzed is irradiated by the electron beam from an electron gun, and the information obtained from the sample and characteristic of the sample is detected for the analysis of the sample. The electron gun and the sample are placed respectively in an electron gun chamber and in a sample chamber. An intermediate chamber is located between the electron gun chamber and the sample chamber. That portion of the sample chamber which contains the sample is protuberant into the intermediate chamber. The intermediate chamber is evacuated to a degree of vacuum higher than the sample chamber but lower than the electron gun chamber.
Abstract:
This concerns an electron beam generator system in which the supply for at least one auxiliary electrode of the electron gun (for example the filament or biasing electrode) is provided by a high frequency oscillator connected to a transformer or other coupling means, the output of which is applied at the electron beam gun column to a component which is itself connected to the output of the high voltage generator; this dispenses with the superimposition of the auxiliary supply on the HT voltage at a remote high voltage generator and with the corresponding auxiliary supply conductor in the conventional high voltage cable between the high voltage generator and the electron beam gun column.
Abstract:
An improved nozzle for an energy beam system including an outer hollow cylindrical sleeve having an internal radial plate across the interior of the sleeve with the plate having axial passages therethrough, an inner hollow tubular sleeve telescopically mounted in one end of the outer sleeve, and an elongated hollow electrode telescopically mounted interiorly of both sleeves and radially spaced apart from the inner sleeve.
Abstract:
This invention relates to an electron beam generating source comprising a cathode and anode, the opposite and facing surfaces of the cathode and anode being flat and parallel so that the electrostatic field formed between the two electrodes is parallel and perpendicular to the surfaces of both electrodes, thereby preventing the electrons emitted from the electron emitter from being affected by lens effects, for example, spherical aberration.
Abstract:
A storage system for the mass recording and readout of digital data with ultra high resolution. An electron beam structure is provided for forming a beam of extremely small focused spot diameter, on the order of 0.1 microns, and high current density capability, on the order of 1,000 amperes per sq. cm., which records data by scanning over defined areas of the storage medium surface and micromachining elemental portions of said medium as a function of beam modulation. Readout may be subsequently accomplished by similarly scanning the beam at reduced power density and detecting electrons that have been transmitted by or reflected from the storage medium.