Optical imaging system for wire array Z-pinch on 'Qiangguang-I'

摘要

A time-resolved optical imaging system is developed for "Qiangguang-I" generator to diagnose the early stage of wire array Z-pinch. The optical imaging system is consisted by several independent modules. Each module includes a set of object lens, an image intensifier, a set of relay lens and a CCD camera. The peak response of the system is at 439 run. The temporal resolution of the system is about 5ns, and the equivalent spatial resolution on the object plane is 6.5 1p/mm when MTF=0.05. A series of images of 12mm diameter 32 × Φ5μm tungsten wire array obtained by the system are shown in this paper. We find that in the 32 × Φ5μm wire array experiments on "Qiangguang-I", from the implosion start to 60% of implosion time, the behavior of single wire is dominant. The implosion time is (113±7) ns and the ratio of acceleration time to implosion time t_a/t_(imp) is about 0.60-0.75. The trailing mass distribution and the m=l mode instability after the stagnation phase are also observed in our experiments.