Title:
電子ビーム装置
Document Type and Number:
Japanese Patent JP4690036
Kind Code:
B2
Abstract:
Axially symmetric magnetic fields are provided about the longitudinal axis of each beam of a multi-beam electron beam device. The magnetic field symmetry is independent of beam voltage, beam current and applied magnetic field strength. A flux equalizer assembly is disposed between the cathodes and the anodes and near the cathodes of a multi-beam electron beam device. The assembly includes a ferromagnetic flux plate completely contained within the magnetic focusing circuit of the device. The flux plate includes apertures for each beam of the multi-beam device. A flux equalization gap or gaps are disposed in the flux plate to provide a perturbation in the magnetic field in the flux plate which counters the asymmetry induced by the off-axis position of the beam. The gaps may be implemented in a number of ways all of which have the effect of producing a locally continuously varying reluctance that locally counters the magnetic field asymmetry. The flux equalizer assembly prevents or substantially reduces beam twist and maintains all of the electron beams of the device as linear beams.
Inventors:
Katerino Mark Jay
Friedlander Fred Eye
Friedlander Fred Eye
Application Number:
JP2004520128A
Publication Date:
June 01, 2011
Filing Date:
July 09, 2003
Export Citation:
Assignee:
Communications and Power Industries, Inc.
International Classes:
H01J23/087; H01J23/10; G01K1/08; H01J3/14; H01J3/20; H01J25/10; H01J29/00; H01J29/46; H01J29/70
Domestic Patent References:
| JP11016504A | ||||
| JP2002530807A | ||||
| JP2162635A | ||||
| JP57500217A |
Foreign References:
| US6147447 | ||||
| FR1324415A1 | ||||
| US3278793 |
Attorney, Agent or Firm:
Sadao Kumakura
Fumiaki Otsuka
Toshio Imajo
Takaki Nishijima
Fumiaki Otsuka
Toshio Imajo
Takaki Nishijima