Electromagnetic lens polepiece structure

摘要

Disclosed is an electromagnetic lens polepiece structure for use in an electron microscope comprising an upper polepiece and an opposite lower polepiece, each having a lens bore, wherein the lens bore portion of the upper polepiece protrudes toward the lens bore of the lower polepiece. The protrudant lens bore portion allows the provision of an X-ray conducting bore for the measurement without disturbing the magnetic field of the lens. This makes it possible a smaller lens bore and, consequently, the spherical aberration is reduced and the resolution of the microscope is improved. The protrudant lens bore structure allows the upper polepiece to be divided into two sections so that the bore section can be replaced easily for the measurement of X-rays.