Abstract: An aberration corrector has two stages of dodecapole (12-pole) elements each of which has first through twelfth poles arranged in this order. Exciting coils of the (4n+1)th poles and the exciting coils of the (4n+4)th poles are connected with a first reversible power supply in series (where n=0, 1, 2) to produce magnetic fields which are identical in absolute value but mutually opposite in sense relative to the optical axis within a plane perpendicular to the axis. The exciting coils of the (4n+3)th poles and the exciting coils of the (4n+2)th poles are connected with a second reversible power supply in series to produce magnetic fields which are identical in absolute value but mutually opposite in sense relative to the optical axis within the plane perpendicular to the axis.

Abstract: An aberration corrector has two stages of dodecapole (12-pole) elements each of which has first through twelfth poles arranged in this order. Exciting coils of the (4n+1)th poles and the exciting coils of the (4n+2)th poles are alternately connected in series (where n=0, 1, or 2) to produce magnetic fields which are identical in absolute value but mutually opposite in sense relative to the optical axis within a plane perpendicular to the axis. The exciting coils of the (4n+3)th poles and the exciting coils of the (4n+4)th poles are alternately connected in series to produce magnetic fields which are identical in absolute value but mutually opposite in sense relative to the optical axis within the plane perpendicular to the axis.

Abstract: A specimen holder has two levers on which probes for current measurement are carried. The levers are in contact with a spherical body, the spherical body acting as a pivotal point. When the levers are pushed by micrometer heads, the probes move in the X-direction. When the levers are pulled, the probes are pushed back by springs and move in the ?X-direction. When the first lever is pushed by a further micrometer head, the first probe rotates about the spherical body and thus moves in the Y-direction. When the first lever is pulled, the first probe is pushed back by the first spring and moves in the ?Y-direction. The second probe is moved along the Y-axis by similarly manipulating a further micrometer head. The two probes can be moved along the Z-axis by similarly manipulating other micrometer heads.

Abstract: Electron beam equipment fitted with a field emission electron gun (FEG) having an extractor electrode, an acceleration electrode, a repeller electrode disposed between the extractor electrode and the acceleration electrode, and a repeller power supply for applying a given voltage to the repeller electrode. Electrons extracted from the emitter collide against the extractor electrode, producing secondary electrons moving toward the acceleration electrode. The secondary electrons are repelled by the repeller electrode and thus prevented from reaching the specimen.

Abstract: A specimen holder has two levers on which probes for current measurement are carried. The levers are in contact with a spherical body, the spherical body acting as a pivotal point. When the levers are pushed by micrometer heads, the probes move in the X-direction. When the levers are pulled, the probes are pushed back by springs and move in the ?X-direction. When the first lever is pushed by a further micrometer head, the first probe rotates about the spherical body and thus moves in the Y-direction. When the first lever is pulled, the first probe is pushed back by the first spring and moves in the ?Y-direction. The second probe is moved along the Y-axis by similarly manipulating a further micrometer head. The two probes can be moved along the Z-axis by similarly manipulating other micrometer heads.