Provided is a compact device which captures, over a large solid angle range, electrically charged particles emitted from a point source and parallelizes the trajectories of said charged particles. The present invention is configured from: an electrostatic lens comprising a plurality of axisymmetric electrodes (10-14) and an axisymmetric aspherical mesh (2) which has a surface that is concave away from the point source; and a flat collimator plate (3) positioned coaxially with the electrostatic lens. The acceptance angle for the electrically charged particles generated from a point source (7) is 30 or greater. The shape of the aspherical mesh (2), and the potentials and the positions of a ground electrode (10) and application electrodes (11-15) are adjusted so that the trajectories of the electrically charged particles are substantially parallelized by the electrostatic lens. The electrostatic lens and the flat collimator plate are positioned on a common axis.

Provided is a compact device which captures, over a large solid angle range, electrically charged particles emitted from a point source and parallelizes the trajectories of said charged particles. The present invention is configured from: an electrostatic lens comprising a plurality of axisymmetric electrodes (10-14) and an axisymmetric aspherical mesh (2) which has a surface that is concave away from the point source; and a flat collimator plate (3) positioned coaxially with the electrostatic lens. The acceptance angle for the electrically charged particles generated from a point source (7) is 30 or greater. The shape of the aspherical mesh (2), and the potentials and the positions of a ground electrode (10) and application electrodes (11-15) are adjusted so that the trajectories of the electrically charged particles are substantially parallelized by the electrostatic lens. The electrostatic lens and the flat collimator plate are positioned on a common axis.

Provided is an ion beam treatment apparatus. The ion beam treatment apparatus includes a laser generation unit, a dividing part dividing a pulse laser beam generated in the laser generation unit into a first laser beam and a second laser beam, a first target part receiving the first laser beam from the dividing part to generate a first ion beam, a second target part receiving the second laser beam from the dividing part to generate a second ion beam, a first path adjusting part adjusting a path of the first ion beam to irradiate the first ion beam to a treated patient, and a second path adjusting part adjusting a path of the second ion beam to irradiate the second ion beam to the treated patient.

Provided is an ion beam treatment apparatus. The ion beam treatment apparatus includes a laser generation unit, a dividing part dividing a pulse laser beam generated in the laser generation unit into a first laser beam and a second laser beam, a first target part receiving the first laser beam from the dividing part to generate a first ion beam, a second target part receiving the second laser beam from the dividing part to generate a second ion beam, a first path adjusting part adjusting a path of the first ion beam to irradiate the first ion beam to a treated patient, and a second path adjusting part adjusting a path of the second ion beam to irradiate the second ion beam to the treated patient.

An electron spectroscopy system and method are disclosed. In another aspect, an ultrabright and ultrafast angle-resolved electron spectroscopy system is provided. A further aspect of the present system employs an electron gun, a radio frequency cavity and multiple spectrometers. Yet another aspect uses spectrometers in an aligned manner to deflect and focus electrons emitted by the electron gun. Moreover, an ultrafast laser is coupled to an electron spectroscopy system. A bunch of monochromatic electrons have their energy compressed and reoriented in an additional aspect of the present system. A further aspect of the present electron spectroscopy system employs adaptive and/or adjustable optics to optimize both time and energy compression. Another aspect provides at least two RF lenses or cavities, one before a specimen and one after the specimen.

An electron spectroscopy system and method are disclosed. In another aspect, an ultrabright and ultrafast angle-resolved electron spectroscopy system is provided. A further aspect of the present system employs an electron gun, a radio frequency cavity and multiple spectrometers. Yet another aspect uses spectrometers in an aligned manner to deflect and focus electrons emitted by the electron gun. Moreover, an ultrafast laser is coupled to an electron spectroscopy system. A bunch of monochromatic electrons have their energy compressed and reoriented in an additional aspect of the present system. A further aspect of the present electron spectroscopy system employs adaptive and/or adjustable optics to optimize both time and energy compression. Another aspect provides at least two RF lenses or cavities, one before a specimen and one after the specimen.

An object of the invention is to stably supply an electron beam from an electron gun, that is, to prevent variation in intensity of the electron beam. The invention provides a charged particle beam device that includes an electron gun having an electron source, an extraction electrode to which a voltage used for extracting electrons from the electron source is applied, and an acceleration electrode to which a voltage used for accelerating the electrons extracted from the electron source is applied, a first heating unit that heats the extraction electrode, and a second heating unit that heats the acceleration electrode.

An object of the invention is to stably supply an electron beam from an electron gun, that is, to prevent variation in intensity of the electron beam. The invention provides a charged particle beam device that includes an electron gun having an electron source, an extraction electrode to which a voltage used for extracting electrons from the electron source is applied, and an acceleration electrode to which a voltage used for accelerating the electrons extracted from the electron source is applied, a first heating unit that heats the extraction electrode, and a second heating unit that heats the acceleration electrode.

A thermionic cathode, an electron emission apparatus, and a method of fabricating the thermionic cathode are provided. The thermionic cathode includes an emitter. The emitter includes a lanthanum hexaboride (LaB.sub.6) crystal having a crystallographic orientation of (310). The operating temperature of the thermionic cathode is greater than 1800 K.

A thermionic cathode, an electron emission apparatus, and a method of fabricating the thermionic cathode are provided. The thermionic cathode includes an emitter. The emitter includes a lanthanum hexaboride (LaB.sub.6) crystal having a crystallographic orientation of (310). The operating temperature of the thermionic cathode is greater than 1800 K.