electron mirror[i′lek‚trän mir·ər]
an electric or magnetic system that reflects electron beams and is designed either to produce electron-optical images by means of such beams or to change the direction of motion of electrons.
Electron mirrors essentially are systems that are symmetric with respect to some axis. Axially symmetric electrostatic mirrors (Figure 1) are used to create accurate electron-optical images of objects. If the last electrode of such an electron mirror is solid and if the electrons undergo a change in direction of motion in the immediate vicinity of the mirror’s surface, then a magnified image of the microscopic relief of the surface can be obtained. This property of electron mirrors is used in the electron mirror microscope.
Cylindrical electron mirrors with a two-dimensional electric or magnetic field (Figure 2) that is independent of the x-coordinate are used to change the direction of electron beams. For electrons moving in the midplane of the mirror, the angle of incidence equals the angle of reflection, as is the case when a light beam is reflected from an optical mirror.
Transaxial electron mirrors (Figures 3 and 4) exhibit small aberrations (image errors) in the direction parallel to the midplane of the mirror.
REFERENCESGlaser, W. Osnovy elektronnoi optiki. Moscow, 1957. (Translated from German.)
Kel’man, V. M., and S. Ia. Iavor. Elektronnaia optika, 3rd ed. Leningrad, 1968.
V. M. KEL’MAN and I. V. RODNIKOVA