显象管电子枪各电极之间存在着很高的电场强度。在典型的彩色显象管中,仅1mm 之隔的两极 G_4G_5(见图1)间就有20KV 的电位差。虽然在设计和制造时竭力采取种种预防措施,管内仍有着产生跳火的趋势。跳火是一种低阻抗放电,电子枪电极流过的电流(瞬间)可达几百 A 乃至几千 A。在大多数情况下,跳火 There is a high electric field strength between the electrodes of the picture tube electron gun. In a typical color picture tube, there is a potential difference of 20 kV between two poles G_4G_5 (see FIG. 1) separated only by 1 mm. Despite all the precautions that have been taken in the design and manufacture, there is still a tendency to cause flashover in the pipe. Flashover is a low-impedance discharge, the current flowing through the gun electrode (instantaneously) can reach hundreds or even thousands of A. In most cases, flash fire