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Possibilities of using transparent polymer materials for production of different optical elements (active elements with lasing dyes, bleachable O-switching filters, etc.) for high-power lasers are discussed. Laser damage resistance of various polymers is particularly investigated. The dependences of laser-induced damage threshold on the initial monomer purity, chemical composition and temperature of polymers, frequency and duration of laser pulses, on the focal spot, as well as statistics and morphology of damages, the accumulation effect in damage in a multiple irradiation regime, light nonlinear scattering and subthreshold UV-glow have been investigated to elucidate the mechanisms of laser-induced damage in polymers. Absorbing defects of different kinds have been established to play an initiating role in the damage process. Purification of the initial monomers was found to result in high values of laser damage thresholds of polymers comparable with those for crystals and glasses, although considerable differences are revealed in the polymer damage characteristics compared to other optical materials. Analysis of these peculiarities is presented and it is concluded that the molecular characteristics of plasticating agents are decisive in the mechanism of microdamage appearance initiated by absorbing defects, and that visco-elastic properties of polymers have a considerable effect on the growth of damages from micro- to macrodimensions. A theoretical model of laser damage, as well as practical, effective ways of increasing laser damage resistance of polymer materials are discussed.

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