Metallic coatings

Metallic coatings provide the broadband reflection than the dielectric mirrors. The reflection from the metallic mirror is less sensitive to the angle of incidence and polarization of the input light. For the broadband applications for example, UV-VIS-NIR and VIS-NIR-MIR metallic coatings are the preferable candidates. But all the metal coatings more or less than the other are prone to oxidation or sulphidation effects. Hence they need to be protected.

Specifications

	Wavelength range	Performance	AOI
Aluminimum Mirrors	UV - VIS - NIR	Refelectivity  > 90%	0 to 45 degree
Enhanced Aluminium Mirrors	550 to 650nm	Refelectivity  >/= 92%	0 to 45 degree
Siver Mirrors	VIS - NIR	Refelectivity  >/= 94%	0 to 45 degree
Gold Mirrors	NIR - MIR	Refelectivity  >/= 98%	0 to 45 degree

ALUMINIUM MIRRORS

Aluminium is the preferable material for UV - VIS applications. It has better reflectance than any other metal in UV. Aluminium mirrors are available as protected aluminium and enhanced aluminium.

Applications

• Astronomy, Spectroscopy, Semiconductor, Lithography, etc
• Cameras and Optical instruments
• Mirrors in binoculars
• Surface mirror on Prism

ENHANCED ALUMINIUM MIRRORS

• Front surface reflection mirrors
• Cameras and Optical instruments
• Sensor technology
• Barcode scanner mirror
• Flatbed scanners
• Copier, Projectors, etc

 

SILVER MIRRORS

Silver has a broad reflection from visible ot NIR. The reflectivity is over 95%. But Siver is very prone to degradation. Its tarnishing feature makes it inferior in space applications inspite of its high reflection. But for the terrestrial applications, properly protected silver is preferred because of high reflection.

Applications

• Astronomical mirrors, Solar concentrators, etc
• On Prism surfaces
• In Optical systems
• Laser projection scanner
• Infrared applications

GOLD MIRRORS

Gold has the absorption in the visible but has the broad and flat reflection spectrum from NIR to MIR region. Gold coated mirrors are the preferable candidates in NIR - MIR region. Bare gold mirror has slightly more reflection than the protected ones. But, in order to to mitigate the effect of tarnish, the mirrors are protected with the help of dielectric top layers on gold.

Applications

• Reflection mirrors for solar concentrators, terrrestial astronomical mirrors,etc
• Reflection mirrors in optical systems withmultiple beam reflections
• On prism surfaces
• Laser applications
• Infrared mirrors