Rainbow Research Optics, Inc. carries a wide range of lens products and can provide customers with fast lens prototyping. Rainbow Research Optics offers a wide range of stock materials.  They offer: BK 7 and synthetic fused silica, e calcium fluoride (CaF2), germanium (Ge), magnesium fluoride (MgF2), silicon (Si), zinc selenide (ZnSe), and zinc sulfide (ZnS).  Selecting the right optical material is important for maximizing light transmitting through a lens element.  For all your prototyping lens needs call at 303-371-300 and visit online at www.rainbowoptics.com.