GB461892A - Improvements in or relating to electron discharge devices - Google Patents

Abstract

461,892. Discharge apparatus. KALLMANN, H. E., and KLEMPERER, O. Aug. 21,1935, No. 23517. [Class 39 (i)] In an electron multiplier in which electrons, produced by secondary emission, oscillate between two electrodes to which alternating potential differences are applied and the electrons are collected by an anode, which surrounds wholly or partly the space between the electrodes and is connected with an output impedance, means, such as a screen grid, is provided for reducing or removing the effect of changes of anode potential on the electrostatic field between the electrodes. As shown. a cylindrical anode 5 and screen grid 4 surround the space between the oscillator electrodes 2, 3, the anode being connected with an output impedance 10, and the screen grid being maintained at a constant potential positive to the mean potential of the oscillator electrodes. The electrodes 2, 3 may be treated to increase the secondary emission, and one or both of the electrodes may be coated with photo-electric material, and exposed to a variable source of light ; or primary electrons, produced by a thermionic cathode, may be controlled by a control electrode in the input circuit. A resonant circuit 6, 7, coupled with a thermionic valve oscillator 9, is connected between the electrodes 2, 3. A magnetic field, parallel with the axis of the anode, may be produced by a coil 12. The anode may consist of a metallic deposit on the envelope and a part or all of the deposit may be transparent. A suppressor grid may be arranged between the grid and anode. In a modification, the anode and grid each consist of two flat plates arranged on each side of the discharge space and connected together. Specification 450,138 is referred to.