Firing characteristics of a low-jitter miniature laser-triggered vacuum switch

A miniature laser-triggered high-voltage vacuum switch with a fused KCl and Ni cathode is discussed. The switch uses metal-ceramic construction with a sapphire window in the anode to allow the laser beam to strike the cathode surface. Reliable triggering is achieved with only 20 mu J of laser energy. The switch was operated with a gap voltage ranging from 500 V to 3 kV, with switching currents up to a 5 kA peak. Switch life greater than 1000 shots without performance degradation has been observed on 50 prototype devices. The function time of the switch varies from 10+or-1 ns at 3 kV to 100+or-50 ns at 500 V.<
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