Comparison of polarization distribution measurement by the LIMM and PWP methods

Two different methods of measurement of polarization distributions in piezoelectric materials, the laser intensity modulation method (LIMM) and the pressure wave propagation (PWP) method, are compared. The two techniques are described, and measurements made on different PVDF-based samples, one with a symmetric and the other one with an antisymmetric structure, are reported. Although the LIMM responds to diffusion of heat and the PWP method to the propagation of a pressure wave, the direct observation of the raw data gives similar information in both cases as far as the symmetry of the polarization distribution is concerned. The specific characteristics of each method are analyzed.<
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