Apparatus and methods for directing a beam of primary electrons along a primary beam path onto a sample are disclosed. In one arrangement, a beam separator diverts away from the primary beam path a beam of secondary electrons emitted from the sample along the primary beam path. A dispersion device is upbeam from the beam separator. The dispersion device compensates for dispersion induced in the primary beam by the beam separator. One or more common power supplies drive both the beam separator and the dispersion device.

Provided is a charged particle beam system capable of scanning a sample in a short time. The charged particle beam system is operative to scan the sample with a charged particle beam and to obtain a scanned image, and includes a magnetic deflector for producing a magnetic field to deflect the beam, an electrostatic deflector for producing an electric field to deflect the beam, and a controller for controlling both magnetic deflector and electrostatic deflector. The controller causes the magnetic deflector to deflect the beam in a first direction and to draw a first scan line, causes the magnetic deflector to deflect the beam in a second direction perpendicular to the first direction, causes the electrostatic deflector to deflect the beam in a third direction opposite to the first direction, and causes the magnetic deflector to deflect the beam in the first direction and to draw a second scan line.