This SBIR Phase I proposal describes a method of fabrication of far IR and THZ range multilayer metal-mesh filters. This type of filter consists of alternative layers of polymer material and structured thin metal films. The proposed filters are radiation hard and lightweight. The fabrication process proposed will increase the availability of such filters and expand the market while reducing the cost and delivery time. In Phase I, it is proposed to develop a process for incorporating the dielectric film in between the metal mesh and to maintain the mechanical integrity over the wide temperature range (from below 4K to 300K). In Phase II, optimized filters will be fabricated and their properties compared with design predictions. Phase III will involve product design, fabricating filter structures to meet customers' physical as well as optical needs, and marketing and sales investments.