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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 laser have also the advantage to be 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, the probe used for a  laser probe  can be made extremely small (smaller than 100 $\mu$m diameter if required), especially if optical fibres are employed. There could be then an interest for endoscopy, by inducing displacement with a simple optic fibre employed,  which can be inserted in small intima or vessels. vessels for example.  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 an elastography method using a laser beam as a shear wave source. 
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