“…Recently, using a variety of compounds of this type, doped by the divalent ions of transition metals (ZnSe : Cr, ZnSe : Fe, CdSe : Cr, etc. ), efficient optically pumped mid-IR lasers have been developed, operating both in the pulsed and cw regimes [15 - 19] and possessing a significant potential for practical applications [20,21]. In this regard, of undoubted interest is the development of the methods of deposition of broadband AR coatings on the surfaces of laser elements on the basis of II - VI crystals, which allow the losses to be minimised both at the pump wavelength and in a broad (~1 mm) spectral range of lasing, while maintaining the radiation resistance of the material.…”