A new method (Q
t method) of gaining a higher time resolution of a shock wavefront structure is proposed for polycarbonate (PC) at particle velocities up to 1 km/s. The modified unsteady wave sensing system (M-UWSS), which we proposed before, using the Q
1 method instead of the conventional Q
2 method on the basis of plate impact experiment with three in-material PVDF gauges is applied to the construction of shock stress-strain curves up to the Hugoniot stress σ
H and the Hugoniot strain ε
H. However, piezofilm thickness has a considerable effect on wavefront structure. Thus, we derive from basic equations of piezoelectricity that the charge release per unit area is proportional to the ratio of the thickness of the shocked region to the total thickness of the piezofilm. It is demonstrated that the rise time of the shock charge density
q in the piezofilm induced by such a shock in the Q
2, Q
1 and Q
t methods, in this order, is markedly decreasing. Among the three methods, the latest Q
t method has the highest accuracy.
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