METALLIC COATING MIRRORS

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Metallic coatings are excellent broadband reflectors.Auminium,silver or gold may be used. Aluminium has the broadest bandwidth extending from 200 nm to the near IR. Silver has the highest average reflectance and gold reflects well at longer wavelengths of infrared but cuts off at about 500 nm giving rise to its distinctive colour.

As metal coatings are prone to oxidation, they are normally protected with a thin layer of silicon dioxide. If a multilayer stack is used instead of a simple dielectric layer, it is possible to enhance the reflectance of metallic mirrors. "Enhanced" metal mirrors should be selected when the highest reflectance is required.

Standard Specifications:
Optical Material: Dimension Tolerance: Clear Aperture: Angular Tolerance: Surface Quality: Wavefront Distortion: Rear Surface Quality: Bevel:	BK7, Silicon +0.0,-0.15mm >90% ±30 arc minutes 20-10 scratch and dig lambda/4 at 632.8nm Fine Ground <0.25mm X 45
Coating Specifications:
Technology: Adhesion & Durability: Angle of Incidence:	Thermal Evaporation(Resistive Heating) Per MIL-C-675A,Insoluble in lab solvent 45 Degrees

Standard For High Power Laser Mirrors: Dimension(mm) T(mm) Shape Optical Material Coating Product Number 10 5.0 Circular BK7 Al Protect UQT-LMCM0101 10 6.0 Circular BK7 Enhance-Al UQT-LMCM0102 10x10 5.0 Square BK7 Silver Protect UQT-LMCM0103 10 5.0 Circular Silicon Gold Protect UQT-LMCM0104 10x10 6.0 Square BK7 Enhance-Al UQT-LMCM0105 15 6.0 Circular BK7 Al Protect UQT-LMCM0106 15x15 5.0 Square BK7 Enhance-Al UQT-LMCM0107 15 5.0 Circular BK7 Silver Protect UQT-LMCM0108 15 6.0 Circular Silicon Gold Protect UQT-LMCM0109 20x20 5.0 Square BK7 Al Protect UQT-LMCM0110 20 5.0 Circular BK7 Enhance-Al UQT-LMCM0111 20 6.0 Circular BK7 Silver Protect UQT-LMCM0112 20x20 6.0 Square Silicon Gold Protect UQT-LMCM0113 25 5.0 Circular BK7 Al Protect UQT-LMCM0114 25 5.0 Circular BK7 Enhance-Al UQT-LMCM0115 25x25 6.0 Square BK7 Silver Protect UQT-LMCM0116 25 5.0 Circular Silicon Gold Protect UQT-LMCM0117 30 5.0 Circular BK7 Al Protect UQT-LMCM0118 30 6.0 Circular BK7 Enhance-Al UQT-LMCM0119 30x30 6.0 Square Silicon Gold Protect UQT-LMCM0120 40 5.0 Circular BK7 Enhance-Al UQT-LMCM0121 40x40 6.0 Square BK7 Al Protect UQT-LMCM0122 50.8 8.0 Circular BK7 Enhance-Al UQT-LMCM0123 50.8x50.8 8.0 Square BK7 Al Protect UQT-LMCM0124 50.8 8.0 Circular BK7 Silver Protect UQT-LMCM0125
Please Contact ultiQuest for other dimensions in prototype and production quantities.
NOTES!
	Enhanced-aluminum reflection mirrors with reflectance improved by about 5% produced by vacuum-depositing several layers of other dielectric films, replacing the protective coating of MgF2 on aluminum mirrors. The enhanced-aluminum mirrors are produced according to specifications given for wavelength and incident angle used, since the protective layer is a dielectric multilayer, no matter how few the number of layers.
	An MgF2 film is vacuum-deposited as the protective coating of aluminum flat mirror, and the reflectance of light in the ultraviolet region can be increased to the maximum (about 85%), by controlling the thickness of this protective coating.
	Gold mirrors of silicon substrates have higher durability than glass substrates because gold coating adheres to silicon much stronger and silicon substrate has higher thermal conductivity (thermal conductivity of silicon is 111 times against glass).
	Since gold coating has an extremely low mechanical strength, it can only be blown by air to clean its coating surface. It must be handled carefully.
	The reflectance curves are based on actual measurements and may be different with production lots.
	The surface flatness is the reflected wavefront distortion of the surface befor coating.
	Be sure to wear laser safety goggles when checking optical path and adjusting optical axis.