摘要 |
Wire-suspended thermionic cathodes provide lower power, further reduction in size, better stability and accuracy, and higher loading then conventional art. The cathodes are too small for use with conventional heaters and so are heated from behind by an electron beam or an intense light beam, such as laser light transmitted via optical fiber to the back of the cathode. The cathodes are electrically isolated from the focus electrode, thus allowing beam cutoff and modulation. |