5. Conclusion

The creation of material flows by photoinduced modification of interfacial tensions, either thermally or through the isomerization of molecules, represents an innovative strategy for the direct conversion of light energy into mechanical work. Demonstrated on simple systems (droplets, floating solids), this technique deserves to be combined with more complex mechanical and chemical systems to develop photomanipulation engineering for safe, clean, economical and high-performance control of various micro- and macroscopic systems by light.