GB529771A - Improvements in or relating to electrical oscillating systems - Google Patents

Abstract

529,771. Cathode-ray tubes; electron oscillators; R÷ntgen-ray tubes. LELAND STANFORD JUNIOR UNIVERSITY, BOARD OF TRUSTEES OF. Feb. 24, 1939, No. 6181. Convention date, March 1, 1938. [Class 39 (i)] A stream of electrons is subjected to an oscillating electric field to alter its velocity in magnitude or direction the resulting changes in the path of the ray separating the electrons into groups which are introduced into an energytransferring oscillating field one at least of these fields being produced by a hollow resonator. Fig. 2 shows an arrangement in which a stream 2 passes through two grids 5 forming part of a hollow resonator 6 thus periodically accelerating the electrons and separating them into groups with different velocities. The stream is then deflected by curved electrodes 16, 17 so that the electrons of lower velocity pass into a resonator 9, of the type described in Specification 517,264. The resonators 6 and 9 are coupled by loops 7, 8. The high-velocity electrons are intercepted by a plate 18, but to prevent overheating of the plate they are first decelerated by a grid 19. The beam may be deflected magnetically instead of electrostatically. Instead of being deflected the beam may be focused magnetically on an aperture in the second resonator and periodically defocused by the changes in velocity. An arrangement in which the beam traces out a circle of varying radius is also described. In the arrangement shown in Fig. 4, the beam is deflected by the oscillating potentials on the portions 39, 39<SP>1</SP> of the wall of the resonator 37 and thus caused to strike alternately on two portions 47, 471 of the wall of the resonator 41. In the arrangement shown in Fig. 6 the beam is similarly deflected by two portions 54 of the resonator 53 and passes through two grids 56, 57 inclined to each other so as to enclose a space at constant potential, the beam receives different accelerations as it passes through a wider and narrow part of this space, and the electrons are grouped longitudinally, the groups passing to a second resonator 59. A similar result may be obtained by inclining the receiving grid of the second resonator to the path of the electrons. Fig. 7A shows a resonator 76 enclosing two plates 77, 78 on to one or the other of which a beam from a cathode 71 is deflected by plates 74, 75 energized from the resonator. A second pair of plates 94, 95 causes a beam from a cathode 91 to enter the resonator at such intervals as to be accelerated from the wall 80 to the wall 801, and after passing through the wall 801 and being returned therethrough by a magnet 96, to be again accelerated in the opposite direction ; the beam after being several times accelerated in this way may strike a cathode 98 to produce X-rays. Specification 523,712 is referred to.