Development and creation of powerful technological lasers re- quires complex solution of problems of optics, quantum elec- tronics and thermal physics. The achieving of stable in time energetic parameters of technological lasers with cooled ele- ments of power (EPO) and adaptive (EAO) optics can be achieved only by a correct choice of their cooling modes, eliminating or compensating negative effects of heating EPO by laser radia- tion because of principal difference of reflectance of the mir- ror surface from I. The convective regime of EPO or EA0 coo- ling is mainly used in laser technique and carried out by pum- ping the coolant through a penetrable disperse compact heat ex- changer, on the work surface of which a thermally thin layer, separating radiation and the coolant liquid in heat changer, is made /1,2/. The intensity of heat transter and therefore, the degree of thermostatting of the reflecting surface of EPO are determined by a large number of design and technological factors not always reproducible in the EPO manufacturing. Ne- vertheless, for EPO, made on the basis of powder porous struc- tures, the level of removing heat fluxes reach 2 . 10' wt/cm2 under the thermal deformation of the mirror surface less than 1pm, the effective heat transfer factor for a heating mirror surface equal to r%, 105 wt/m2 . Ã‚Â°C in this case /2/.