A formula for the diameter definition of the spot of focused laser emission at the known quality parameters of BPP and M2 ray is obtained. A formula for the definition of the optimum focal distance of an optical path in a fiber laser is presented. An alignment chart is formed for the definition of the optimum value of the focal distance of the optical system in a fiber laser.

The investigation results of the repeated irradiation impact of silver nano-particles upon their dimensions are shown. In particular, the attention is paid to the particles with dimensions from 10 to 40nm. As a result of the researches there were defined the regularities in dimension changes of particles at different degrees of irradiation. These results may be used for the development of strategies in nano-particle dimension control, which is significant for the laser synthesis method from the point of view of its competitive ability with chemical methods.

The results of the experimental investigations of water properties impact (distilled thorough treated water washed with helium), ethyl alcohol and acetone upon a process of Cu nano-particle obtaining by a laser ablation method are shown. Differences are defined in the spectra of the absorption of Cu nano-particle colloidal solutions, and also in the forms and dimensions of nano-particles obtained in different liquids.

In this paper the application of laser cutting methods for polymeric materials working is under consideration. The authors analyze the laser beam effect upon polymers reasoning from the peculiarities of their structure and properties. The methods to eliminate defects at polymer laser cutting, the methods to increase the interaction effectiveness of radiation with material, process quality are offered. To determine the dependences of a cut width and a value of flash formed at the beam input and its output of material worked there were carried out experiments at different rates and constant capacity of CO2-laser. According the results of the researches carried out the optimum working modes were established.