An interference electron microscope, comprising: an electron source; an acceleration tube for accelerating an electron beam emitted from the electron source to a predetermined speed; an illumination-lens system for radiating the electron beam to a sample and including at least one electron lens; a sample holding unit for holding the sample; an objective lens system for imaging an image of the sample and including at least one electron lens; an imaging lens system for imaging the image of the sample imaged by the objective lens system in a magnified or contracted state and including at least one electron lens; an observation surface used for observing the image of the sample imaged by the imaging lens system; an observation/recording system for observing or recording the image of the sample imaged on the observation surface; a first electron biprism disposed between the acceleration tube and the illumination-lens system; and a mask disposed between the acceleration tube and the first electron biprism, wherein the objective lens system or the imaging lens system includes at least one electron biprism, and wherein, in operation, the electron beam is split into a first electron beam and a second electron beam by the mask, current densities of the first electron beam and the second electron beam on a surface of the objective lens system where the sample is positioned are controlled by an optical action of the illumination-lens system, an electro-optical length between the first electron beam biprism and the surface of the objective lens system where the sample is positioned is controlled by the optical action of the illumination-lens system, and the mask is imaged on the surface of the objective lens system where the sample is positioned and mutually different first region and second region on the surface of the objective lens system where the sample is positioned are irradiated by the optical action of the illumination-lens system, positions of the first region and second region are controlled by a deflecting action on the electron beams by the first electron beam biprism or the optical action on the first electron beam and the second electron beam by the illumination-lens system, the first electron beam and the second electron beam are superposed on the observation surface by the electron beam biprism included in the objective lens system or the imaging lens system, and a superpose region on the observation surface where the first electron beam and the second electron beam are superposed is observed or recorded by the observation/recording system. an electron source; an acceleration tube for accelerating an electron beam emitted from the electron source to a predetermined speed; an illumination-lens system for radiating the electron beam to a sample and including at least one electron lens; a sample holding unit for holding the sample; an objective lens system for imaging an image of the sample and including at least one electron lens; an imaging lens system for imaging the image of the sample imaged by the objective lens system in a magnified or contracted state and including at least one electron lens; an observation surface used for observing the image of the sample imaged by the imaging lens system; an observation/recording system for observing or recording the image of the sample imaged on the observation surface; a first electron biprism disposed between the acceleration tube and the illumination-lens system; and a mask disposed between the acceleration tube and the first electron biprism, wherein the objective lens system or the imaging lens system includes at least one electron biprism, and wherein, in operation, the electron beam is split into a first electron beam and a second electron beam by the mask, current densities of the first electron beam and the second electron beam on a surface of the objective lens system where the sample is positioned are controlled by an optical action of the illumination-lens system, an electro-optical length between the first electron beam biprism and the surface of the objective lens system where the sample is positioned is controlled by the optical action of the illumination-lens system, and the mask is imaged on the surface of the objective lens system where the sample is positioned and mutually different first region and second region on the surface of the objective lens system where the sample is positioned are irradiated by the optical action of the illumination-lens system, positions of the first region and second region are controlled by a deflecting action on the electron beams by the first electron beam biprism or the optical action on the first electron beam and the second electron beam by the illumination-lens system, the first electron beam and the second electron beam are superposed on the observation surface by the electron beam biprism included in the objective lens system or the imaging lens system, and a superpose region on the observation surface where the first electron beam and the second electron beam are superposed is observed or recorded by the observation/recording system.