Charged particle beam system

There is provided a charged particle beam system capable of determining the type of each cartridge precisely. An electron microscope that embodies the charged particle beam system includes a discriminator for determining the type of each cartridge based on the range or distance measured by a laser range finder. Plural cartridges are received in a magazine. The laser range finder measures the range to a selected one of the plural cartridges which is placed in a measurement position. A first cartridge of a first type included in the plural cartridges has a first measurement surface at a first distance to the laser range finder when placed in the measurement position. A second cartridge of a second type has a second measurement surface at a second range to the laser range finder when placed in the measurement position.