In an SEM provided with an ExB deflector for deflecting secondary electrons outside an optical axis of a primary electron beam between an electronic source and an object lens for condensing the primary electron beam and irradiating a sample with the beam, a unit to decelerate the secondary electrons deflected in the ExB deflector, and a magnetic generator for deflecting the decelerated secondary electron are provided, and a plurality of energy filters and detectors are arranged around the magnetic generator. That is, by separating loci of the secondary electrons incident on the energy filters and of the secondary electrons reflected at the energy filters by the magnetic generator, both of the secondary electrons are concurrently detected.