A vacuum tube for producing a wide high-uniformity beam of fast accelerated electrons. The tube comprises an evacuated enclosure provided with an electron transparent window and containing an elongated cathode, accelerator electrodes and a control electrode formed by sleeves electrically insulated from one another and brought to separately adjustable potentials.

Vacuum tube for generating a wide beam of fast electrons

Cooling apparatus with laminar flow for electron permeable windows

An electron beam (E-beam) laser has a vacuum chamber in which an E-beam terminal generates a directed stream of electrons. A primary foil which seals the chamber is in the path of the stream of electrons and permits passage of the stream of electrons to the exterior of the chamber. A cathode is positioned closely adjacent the primary foil and an anode is spaced from the foil to form an elongated laser cavity between them. The electrodes are maintained at a high electrical potential which, along with the electron beam, molecularly excites a gaseous working medium between the electrodes. A secondary foil is positioned between the cathode and the primary foil. The secondary foil is formed from material transparent to the passage of electrons but which forms a physical barrier between the primary foil and the cathode. This prevents rupturing of the primary foil when the cathode material sputters off upon arcing between the anode and the cathode.

Pararas John L

Papers

Fluid cooled multi-foil radiation beam window for high power beam tubes