magnetrón
Magnetrón is a high-power vacuum tube that generates microwaves. It operates based on the principle of the interaction between electrons and magnetic fields in a resonant cavity. Electrons emitted from a cathode are accelerated towards an anode by a high voltage. A strong magnetic field, typically produced by permanent magnets, is applied perpendicular to the electric field. This causes the electrons to spiral as they move, interacting with the electromagnetic fields within the anode structure, which is divided into resonant cavities. This interaction causes the electrons to oscillate and generate microwave radiation. The frequency of the generated microwaves is determined by the geometry of the resonant cavities. Magnetrons are commonly used as the source of microwaves in domestic microwave ovens, as well as in radar systems, industrial heating, and medical applications. Their ability to produce high power efficiently at microwave frequencies makes them a crucial component in these technologies. Early magnetrons were developed in the late 1930s and played a significant role during World War II, particularly in radar technology.