COPPER MIRRORS
Copper is the most popular material from which to make infrared mirrors, and is the most common mirror type for CO2 laser cutting, engraving and welding. Copper metal has high thermal conductivity, high heat capacity, and when freshly polished uncoated copper surfaces have a high natural reflectivity too.
Because polished copper surfaces react with the atmosphere and lose reflectivity, most, but not all components, are generally used with a coating, to improve reflectivity, durability, or alter polarisation on reflection. We offer several metal reflector coatings,
Electroplated Gold
MaxR with zero phase shift for 10.6um
L/4 reflective phase retarder for 10.6um
Protected silver for broad infra red use.
To improve the laser damage resistance, and reduce scatter, Copper mirrors have a thin intermediate layer of electroless nickel deposited. This gives an amorphous, non crystalline, surface of exceptional smoothness. Electroless Nickel also protects the whole of the mirror from oxidation, and prevents contamination of, or reaction with, the lasing gas, such as in sealed resonators.
Copper mirrors are chemically polished, the surfaces are super smooth and are free of imperfections from turning lines, fly cutting arcs, and diffractive patterns common on diamond turned optics. This gives a high laser damage resistant, super smooth, low scatter surface.
Finally, our proprietary stress relieving and heat treatment gives long term stability and performance, across a wide range of operating temperatures.
For the highest powers, and for maximum stability, internal water cooling channels can be machined into the mirror itself.
As Copper is readily machinable we offer a huge range of mirror shapes and sizes, such as prisms, axicons, rectangles, chopper wheels, knife edges and shutters. By engineering in features such as dowel holes, tapped and helicoiled holes, or flanges, a well designed copper mirror can save costs in mounting and assembly.
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