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For In a context of  elastography measurements, Muthupillai et al. assumed that a displacement of a few hundreds of nanometers should be sufficient to perform shear wave elastography \cite{7569924}. However, displacements of the order of the micrometer is usually required, which is higher than the displacement observed at 10 mJ (thermoelastic regime) and about the same order of magnitude at 200 mJ (ablative regime). The minimum energy of our laser (532 nm, 10 ns, 10 mJ, 5 mm diameter) used in our experiments to get a shear wave is still 2.5 times above the maximum exposure permissible as given by the current American National Standard Institute (Z136.1-2000) for skin \cite{ANSIZ1361}, a value which is also used in typical photoacoustic imaging experiments with 532 nm Q-switch Nd:YAG lasers \cite{Ku_2005}. This value is also a few hundred times lower than the typical energy used for skin tatoo removal, which use same type of lasers \cite{8352621}. In summary, this study presented observation of elastic shear waves generated in soft tissues using a laser beam. The involved phenomenons were investigated and we distinguished thermoelastic and ablative regimes. Experiments in chicken breast sample showed the feasibility of the elastography method using a laser beam as a shear wave source.