电晕在电晕放电中在高压电极出现的一种微弱光辉,常伴随有朝向低压电极的电流 A faint glow enveloping the high-field electrode in a corona discharge, often accompanied by streamers directed toward the low-field electrode.
中间极,二次发射电极一种用于一定电子管作第二次发射电极 An electrode used in certain electron tubes to provide secondary emission.