LBTEK metallic coated concave mirrors use Borofloat 33 substrates with a metallic coating (silver coating with a protective layer) on the concave surface. This reflective coating offers high reflectance (Ravg > 96%) over the wavelength range of 450 nm to 20 μm, making it well-suited for collimating, focusing, and imaging of beams without introducing chromatic aberration. Metallic coatings are prone to oxidation, discoloration, or peeling in high-humidity environments; the SiO2 protective layer isolates the metallic coating from direct contact with air, preventing oxidation and preserving optical performance. Currently, LBTEK offers silver-coated concave mirrors in three sizes (Ø12.7 mm, Ø25.4 mm, and Ø50.8 mm) and seven focal lengths (-25 mm to -500 mm). In addition to standard products, LBTEK provides custom solutions for size, focal length, and wavelength range. For further assistance, please contact LBTEK technical support.