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Shear wave frequency in elastography ranges typically between 50 and 500 Hz, with higher frequency meaning better spatial resolution. The experiments demonstrated that these frequencies can be reached, although the mechanism explaining this particular frequency is not clear yet.  The laserhave  also has  the advantage of being non-contact and totally remote. For example, Li et al. have proposed to induce surface acoustic waves by laser to measure elastic properties of biological thin layers like skin or cornea \cite{li2011elastic}, \cite{li2014laser}. Moreover, a laser probe can be made extremely small (smaller than 100 $\mu$m diameter if required), especially if optical fibres are employed, for example for insertion in small vessels. Additionally, the shear wave source emits very weak electromagnetic noise (apart from the laser device itself), so it can be quite convenient for magnetic resonance elastography measurements, which are currently using external drivers or non-magnetic ultrasound probes. Moreover, the laser probe could help to shape precisely the shear wave shape, with focusing capabilities for example (see for example \cite{noroy1993laser}). In summary, this study presented observation of elastic shear waves generated in soft tissues using a laser beam. The involved phenomenon was investigated. Experiments in chicken breast sample showed the feasibility of the elastography method using a laser beam as a shear wave source. 
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