Small thermal expansion for high-temperature applications 

ZERODUR® K20 has been optimized to withstand higher application temperatures than ZERODUR®. The material is white in color and offers good infrared (IR) transmittance between 3.5 and 5 μm and homogeneous high reflectivity properties.
The non-porous ZERODUR® K20 exhibits good polishing abilities, excellent vacuum properties and can be delivered as small, high-precision optical components.