彩色显象管中非轴对称场空间电荷数值计算

NUMERICAL CALCULALION OF SPACE CHARGE EFFECT OF ASYMMETRICAL FIELD IN THF COLOR PICTURE TUBE

本文采用电子云模型确定电荷在空间的分布方法,简化了三维场下电子束空间电荷效应的计算,在彩色显象管漂移空间较长的情况下,计算精度仍可得到保证。本文对37cm彩管中BPF枪进行了计算,计算结果与实测数据吻合较好。通过数值计算发现,在主透镜及漂移区内由于空间电荷效应的影响,电子束增大20～25%。

With the aid of electron clouds concept, the poisson′s field distribution and electron trajectories are calculated in this paper. The result of computation shows that the effect of space charge in the main lens and the drift region makes the spot size at the screen 20～25% larger than that in Laplace′s fields both calculated and experimeatal results are well coincident.