“…The method is based on the property of laser radiation, scattered by a rough (structured) surface, to form a speckle pattern [12,13,21], and carbon nanoparticles are employed for the study of this pattern. The synthesized carbon nanoparticles [20], about 50-70 nm in size, with a significant absorption at the wavelength of 405 nm and moderate absorption at the wavelength of He-Ne laser radiation, are able to move within aqueous suspensions under the action of optical forces generated by the internal energy flows in the light field [21,22]. Intensively absorbing the radiation of the semiconductor laser (405 nm), the particles can be kept at the special regions of the optical intensity distribution under the action of the gradient optical forces [22,23].…”