A microtron is a type of particle accelerator concept originating from the cyclotron in which the accelerating field is not applied through large D-shaped electrodes, but through a linear accelerator structure. The classic microtron was invented by Vladimir Veksler. The kinetic energy of the particles is increased by a constant amount per field change (one half or a whole revolution). Microtrons are designed to operate at constant field frequency and magnetic field in the ultrarelativistic limit. Thus they are especially suited for very light elementary particles, namely electrons. A microtron is a type of particle accelerator concept originating from the cyclotron in which the accelerating field is not applied through large D-shaped electrodes, but through a linear accelerator structure. The classic microtron was invented by Vladimir Veksler. The kinetic energy of the particles is increased by a constant amount per field change (one half or a whole revolution). Microtrons are designed to operate at constant field frequency and magnetic field in the ultrarelativistic limit. Thus they are especially suited for very light elementary particles, namely electrons.