为了检查LaB_6单晶阴极的性能,在同样的条件下测量了常规发叉式钨丝阴极的亮度和电流稳定度,结果表明:LaB_6阴极不仅亮度高(20kV时,2×10~5A/cm~2·str.),而且电流稳定度也好(没有任何辅助电流稳定器情况下为1×10~(-3)h~(-1)),只要系统的真空度足够好,即优于1×10~(-5)Torr,亮度和寿命提高一个数量级是容易的。 <100>,<110>LaB_6阴极的最大亮度为较高偏压下得到单一斑点的交叉点亮度的二倍。 In order to check the performance of LaB_6 single crystal cathode, the brightness and current stability of conventional hairpin tungsten cathode were measured under the same conditions. The results show that LaB_6 cathode not only has high brightness (2 × 10-5A / cm ~ 2 · str.), And the current stability is also good (without any auxiliary current stabilizer in the case of 1 × 10 -3 h -1), as long as the system vacuum is good enough, that is better than 1 × 10 ~ (-5) Torr, brightness and life expectancy increased by one order of magnitude is easy. The maximum brightness of <100>, <110> LaB_6 cathodes is twice the brightness of the cross point at which a single spot is obtained at a higher bias voltage.