What do we Need to Generate X-rays?
The generation of x-rays requires a Tungsten cathode and anode encased in a Pyrex glass vacuum tube.1,3,7 The thermionic emission is responsible for generating electrons at the level of the heated cathode filament, and the anode serves as the target for the accelerated electrons. A step-up and a step-down transformer help to transform the regular 110V alternating current to a high voltage at the level of the tube (more than 50 kV), and a low voltage at the level of the filament (10 V), respectively.1,3,7
A focusing cup houses the cathode helps prevent the electrons from repelling each other away from the ligament and allows the stream of electrons from the cathode to anode to be controlled. A dead-man switch timer is connected to the circuit and controls the time the electrons travel from the filament to the target (Figure 3).1,3,7
Figure 3. Schematics of an x-ray tube.