Zerodur

glass

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Last updated

July 15, 2026

Quick Summary

Zerodur is a brand name for a type of glass-ceramic known for its extremely low coefficient of thermal expansion, meaning it barely expands or contracts with changes in temperature. This property makes it ideal for precision applications like telescope mirrors and scientific instruments where dimensional stability is crucial. Developed in Germany, this specialized glass was initially created for thermometers and optical equipment, showcasing its resistance to heat and shock. Its composition, often a borosilicate glass, allows for exceptional stability across a wide range of temperatures.1

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telescope
Evolution of the optical telescope
…in the Canary Islands, and Zerodur was used for the 10.4-metre (410-inch) reflector at the Gran Telescopio Canarias in the Canary Islands.
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…in the Canary Islands, and Zerodur was used for the 10.4-metre (410-inch) reflector at the Gran Telescopio Canarias in the Canary Islands.
Read More