| 摘要 |
Disclosed is an electron-beam system comprised of an iris having an aperture of predetermined shape; a cathode for emitting electrons from an area which is substantially smaller than the aperture; a lens system for directing the emitted electrons along a path through the aperture to form a magnified image of the aperture; and a target for the electrons which is placed along the path of the aperture's demagnified shadow.
|
