公开(公告)号：US5861712A

公开(公告)日：1999-01-19

申请号：US675552

申请日：1996-07-03

Applicant: John Beetson ,  Andrew Knox

Inventor： John Beetson ,  Andrew Knox

IPC: B41J2/447 ,  G09G1/20 ,  H01J3/24 ,  H01J29/46 ,  H01J29/68

CPC classification number: H01J29/68 ,  B41J2/4476 ,  G09G1/20 ,  H01J29/46 ,  H01J3/24 ,  H01J2329/00

Abstract: An electron source having a cathode and a permanent magnet perforated by a plurality of channels extending between opposite poles thereof. The magnet generates, in each channel, a magnetic field which forms electrons received from the cathode into an electron beam for guidance towards a target. An electrode grid is disposed between the cathode and the magnet for controlling flow of electrons from the cathode into each channel. A magnetic field null region of each magnetic field is positioned at a location remote from the electrode grid. Because the null region is positioned remotely from the grid electrodes, flow of electrons can be improved without increasing electrode drive voltage.

Abstract translation: 电子源具有阴极和永久磁铁，该多个通道在其相对极之间延伸。 在每个通道中，磁体产生形成从阴极接收的电子到电子束的磁场，用于向目标引导。 电极栅格设置在阴极和磁体之间，用于控制电子从阴极到每个通道的流动。 每个磁场的磁场零区域位于远离电极栅格的位置。 因为零区域远离栅格电极，所以可以在不增加电极驱动电压的情况下改善电子流。