Metallic Coating
 
  • Broadband reflectors
  • Not sensitive to polarization and incident angle.
  • Low damage threshold, can NOT be used on high power/energy lasers.

Metallic coatings make very broad bandwidth reflectors. Usually it is best to protect the coatings with a durable dielectric layer as they are very soft and susceptible to scratching. The efficiency of metallic reflectors falls off at shorter wavelengths but this may be enhanced by the application of a multi-layer dielectric thin film stack. The table shows the reflectance. of each of the metals without any protection or enhancement. Protected metallic coatings have a dielectric coating layer over the metallic layer to protect the coating from being oxidized in the air or from scratched. For enhanced metallic coatings, a stack of dielectric layers are added on the metallic coating to increase reflectance for a particular wavelength range.

We provides metallic high reflective coatings by material of Au, Ag and Al. These coatings are applied to where the consistent high reflection in a wide spectral rang is necessary. Their reflectivity are not higher than dielectrics HR coatings, but their HR spectrum can over near-UV, visible and near-IR. In order to prevent these metallic coatings from oxidization, these coatings have been deposited on a layer of dielectrics coating.

Reflectance of Metallic Coating at Normal Incidence