In the paper, a method of measuring the kinematic visicosity of liquid medium based on stimulated Brillouin scattering (SBS) at different temperatures is proposed. The kinematic visicosity of liquid medium, which is related to the temperature, greatly affects the gain coefficient of medium and SBS characteristics. Therefore the kinematic visicosity at different temperatures can be measued by the reflectivity of SBS. In experiment, the kinematic visicosities of water at different temperatures are determined based on SBS in continuum's Nd:YAG seed-injected laser and compared with the results measured from kinematic viscosimeter, and the relative error of the experiment results is less than 5%.

In order to improve the optical limiting performance based on stimulated Brillouin scattering (SBS), an optical limiter based on the combination of SBS and metal-phthalocyanine complexes (MPCs) is proposed in this paper. The output energy of the combination optical limiting designed based on SBS followed by MPCs shows flatter characteristic. The dependence of the output energy of optical limiting based on this combination approach on the input light intensity is numerically simulated, and validated in a continuum Nd:YAG seed-injected laser system. The theoretical and the experimental results indicate that the output energy based on this approach has a flatter characheristie than based on a single SBS.