The triggering characteristics of LTVS（laser triggered vacuum switch

LTVS）were analyzed in the view of micro-current. A micro-current test circuit was designed

and a constant voltage

which is unable to turn on the switch

was applied on the switch to analyze the development of initial plasma within the switch before it turned on. The experiment revealed that under the effect of dual-pulse laser

the micro-current of flat-type LTVS increased with the increase in the applied voltage

and continuous twice irradiation of pulsed laser on the target material of the flat-type LTVS produced more initial plasma

so that the conduction time delay and jitter time delay of the switch reached nanosecond level. The result shows the dual-pulse laser trigger mode is beneficial to reduction of the triggering energy required for conduction of the switch

and the mode also contributes to the miniaturization of the overall switch device and its practical design.