Performance of parallel-driven flashlamps suitable for photoinitiated lasers

A simple method for efficient generation of short (microsec)-duration uv pulses using meter-long flashlamps is described. A four-lamp version of this system has been constructed and tested for application to initiation of pulsed F2 - D2(H2) lasers. Conversion of stored capacitor energy into radiation in the F2-dissociation continuum (240-360 nm) was measured to vary between 12 and 16% as flashlamp pressure was increased from 20 to 100 torr; corresponding uv pulsewidths were observed to vary from 2 to 2.5 microsec. Comparable efficiencies for microsec-duration flashlamps have heretofore been attained only by use of simmer or pre-pulse conditioning. Synchronous lamp triggering and equipartitioning of electrical energy among parallel flashlamps were not observed to be problems in the present design. For flashlamps of 1-meter length or greater, short-pulse operation can be achieved by no other method.