HIGH ENERGY ELECTRON BEAM DOSE FLATTENING FILTER

摘要

PURPOSE:To obtain the title filter low in the energy loss of electron beam and the mixing degree of X-rays by mounting the first scattering body for scattering electron beam, the second scattering body whose central part is composed of an electron impervious material and a shape, and the second scattering body holder composed of material quality low in the energy loss of the electron beam. CONSTITUTION:The first scattering body 1, the second scattering body 3 composed of a substance and shape capable of transmitting no electron beam and the second scattering body holder 7 for holding the second scattering body at a predetermined position composed of a substance low in scattering and energy loss are mounted. By this constitution, the electrons scattered in a region B among electrons scattered by the first scattering body 1 are stopped by the second scattering body 3 and not transmitted therethrough but electrons scattered in a region C pass through the second scattering body holder 7. At this time, the electrons pass through the second scattering body holder 7 without almost generating energy loss and scattering and scattered in an electron beam dose measuring box. By this method, a dose becomes uniform from the center to the periphery at a dose measuring position.