GB386282A - Improvements relating to electron discharge tubes - Google Patents

Abstract

386,282. Discharge apparatus. ALLGEMEINE ELEKTRICITATS-GES., 2, Friedrich Karl-Ufer, Berlin. Sept. 24, 1932, No. 26592. Convention date, Sept. 25, 1931. [Class 39 (i).] A cathode-ray tube containing a small quantity of gas, has a small bent tube of conducting material into an opening of which the electron beam from the cathode is directed coaxially. As shown in Fig. 1, the tube 3 is of copper, preferably silvered internally, and has a widened inlet consisting of a molybdenum tube 5 facing the cathode 2 ; or the tube 3 may be of insulating material silvered internally. The tube 3 may act as the anode, or a separate anode may be arranged between the tube and the cathode, and the tube may be maintained at the anode or other potential. The beam passing to the fluorescent screen 7 may be deflected by plates 8 or magnetically. In the arrangement shown in Fig. 2, a flexible copper tube 9 connects two vessels 10, 11, the cathode 12 being mounted in the vessel 10, and the deflecting plates 19 and screen 20 in the vessel 11. Copper caps 13, 17 connect the tube with the vessels. Deflecting coils 18 may b:earranged at the end of the tube. The vessel 10 : is connected with an evacuating pump, and the vessel 11 contains a small amount of gas. With this arrangement the beam may be bent into ,such a direction that.it is not affected by the earth's magnetic field.