Effect of preheat on shock wave measure technique in laser indirect-drive experiment

In this paper, the active velocity interferometer system for any reflector has been presented to adjust the thickness change. The expansion was calculated under different laser energy and target design. The experiment shows, the expansion is about 2.1 m under 5 kJ indirect single-ended drive. The thickness change can be obtained after calculating the fringe change. After the optimization of target design in double-ended drive experiment, the step thickness can be achieved accurately with corrected preheat effect on the thickness. The time for shock wave breaking out on the step target can be achieved with the optical stream camera. Under the condition of steady velocity in step target, the shock wave velocity can be gotten from the experiment data. This technique is suitable for the shock wave experiment with radiation drive, and provided the shock wave for equation of state with high accurate.