Plymouth Grating Laboratory is the primary commercial source for the largest Diffraction Gratings in the world and is dedicated to making the highest quality gratings available. We specialize in diffraction gratings with periods of 200 nm to 20,000 nm on a substrate size of 1 meter x 0.6 meters with excellent diffraction wavefront characteristics. We manufacture Multi-layer Dielectric reflection, metal reflection, transmission, and amplitude gratings