DE619842C - Electric discharge tubes with perforated anode for emitting cathode rays - Google Patents

Description

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In the operation of cathode ray tubes, especially for physiological examinations or treating the sick, is 'em' essential Requirement that the cathode ray window be at ground potential. The known cathode ray tubes for two-pole connection to the high-voltage source can therefore not be used without can also be used.

The well-known cathode ray tubes, in which the anode and the window open together Ground potential and only the cathode is connected to the high voltage source, require special high-voltage * 5 doors.

Both disadvantages outlined are eliminated by the subject matter of the invention. the The cathode ray tube described here allows a two-pole connection to the high-voltage device, whereby the radiation exit window is at ground potential.

The discharge tube according to the invention 'contains a perforated anode, on the one hand a hot cathode and on the other hand a metal tube opposite. The latter is on his from the end facing away from the anode closed by a grounded cathode ray exit window and from the electrodes of the tube through parts of the wall against high voltage isolated. The metal tube extends in the longitudinal direction of the tube and forms in a known manner Way a Faraday cage through which the electrons move at a constant speed get to the Lenard window and exit the tube through it.

Appropriately, a part of the tube wall at the level of the anode can be designed and connected in this way be (for example made entirely of metal) that it has the potential of the anode.

The figure shows a cylindrical cathode ray tube with a wall 1 preferably made of glass. The anode is formed by the metal ring 2 which, fused to the glass wall 1, also forms part of the vessel wall. The cathode3 is surrounded by a collecting device, which the direction of the cathode rays in a desired manner ^; favored on the radiation exit window. The Faraday cage is delimited by an essentially cylindrical hollow body 4 which can be conductively connected to the Lenard window 5.

A high-resistance resistor 6 can be switched on between earth and anode. The same is designed to be changeable as far as possible and can consist of an ohmic resistance, an alternating current resistor or a high vacuum resistor. The controllability of the resistance is particularly convenient with a high vacuum resistor with hot cathode.

Claims (3)

Patent claims: 1. Electric discharge tube with perforated Anode for emitting cathode rays, characterized in that the anode has a hot cathode on one side and on the other side a metal tube is opposite, which at his of the end facing away from the anode is closed off by a grounded cathode ray exit window and from the anode by parts the tube wall is insulated against high voltage. 2. Electrical discharge tube according to claim i, characterized in that the metal pipe extends in the longitudinal direction of the pipe and is surrounded by an insulating Part of the tube wall is surrounded, which it from the anode against high voltage isolated. 3. Electrical discharge tube according to claim 2, characterized in that a Part of the tube wall, for example made entirely of metal, at the level of the anode possesses the potential of the anode.