| 摘要 |
A multipixel electron emission source is generated by separating a point electron source from a plasma region. The point electron source produces an electron beam that is passed through the plasma region. The plasma region diffuses the electron beam thereby producing electrons with uniform energy. Moreover, the maximum current of the device is advantageously controlled by the maximum electron current produced by the point electron source and not the characteristics of the plasma and wall interactions as found in conventional devices. The electrons are then pulled out of the plasma region by an aperture grid that is also used as a blanking array. A focusing chamber is positioned down stream of the plasma region and aperture grid. The aperture grid includes a base electrode and a blanker electrode, which is isolated from the base electrode. The base electrode is held at a potential. In the off state, the blanker electrode is floating permitting the blanker electrode to become negatively charged from the electron stream. Once negatively charged, the blanker electrode pinches off the electron stream. In the on state, the blanker electrode is switchably coupled to the base electrode which drains the negative charge and permits the electron stream to pass. The aperture grid may be an integrated blanking and switching device.
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