The silver halogenide crystals transparence from visible to far-infrared region, nonhygroscopicity, nontoxicity and high plasticity are the great advantages in front of other optical materials. It is the kind of material that determines the technical characteristics of the basic optical materials and fiber-optical elements for different purposes. The radiation-resistant and transparent in 0,40–45 region new AgBr—TlI, AgCl_хBr_1–х crystals, including those, that are alloyed with TlI, were elaborated. The growth technologies, including unconventional multicomponent homogeneous single-phase charge and single crystals growth on the new KPC-01 device, were developed. On the base of theoretical calculations there was simulated the structure of the new defective crystals, which are the solutions of substitution. The unique crystals properties, plasticity, nonhygroscopicity, and the wide range of transparence in generally, provide the production of single- and multimode light guides of the new generation for middle and far-infrared regions.