Charged particle optical system and charged particle apparatus

A charged particle optical system configured to converge charged particle beams, which is emitted from a charged particle beam source, to an object, the charged particle optical system comprising:

• a permanent magnetic lens configured to form a magnetic field parallel to an optical axis of the charged particle optical system in a first region;
• an electromagnetic lens figured to form a magnetic field parallel to the optical axis of the charged particle optical system in a second region;
• and
• an electrostatic lens configured to form an electrostatic lens field coaxial with the optical axis of the charged particle optical system in a third region,
• wherein at least some of the first region, the second region, and the third region overlap each other in an optical axis direction of the charged particle optical system.

A charged particle optical system configured to converge charged particle beams, which is emitted from a charged particle beam source, to an object, the charged particle optical system comprising:

• a first electron optical system configured to control a current density distribution of the charged particle beam;
• and
• a second electron optical system configured to converge charged particle beams from the first electron optical system to the object,
• wherein the first electron optical system provides a magnetic field to charged particle beam passing through the first electron optical system so that a current density distribution of the charged particle beam entering the second electron optical system in a plane perpendicular to the optical axis is increased in an outer region which is outside of an inner region including the optical axis.