Paper
2 September 2014 Study of inverted thermal evaporation for large mirror
Author Affiliations +
Proceedings Volume 9280, 7th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Large Mirrors and Telescopes; 92800H (2014) https://doi.org/10.1117/12.2068419
Event: 7th International Symposium on Advanced Optical Manufacturing and Testing Technologies (AOMATT 2014), 2014, Harbin, China
Abstract
From October 2010 to December 2012, the systematic study of the protected aluminum coating which is thermally evaporated downwards for large primary mirror had been developed. By adjusting the structure, it makes the physical nonuniformity of the bare aluminum films in the diameter of 1.8m drop to 4.18%, and the average reflectivity meets 95.09% in the band 400nm-2500nm. The optimized parameters suggest that the SiOx (1<x<2) protective film with the oxygen flow of 50sccm has excellent environmental stability, and the average reflectivity of the protected aluminum coating reduces just less than 5%. Further, the SiOxNy protective film which is formed with 25sccm nitrogen flow not only has the environmental adaptability as the SiOx film but also resists to the salt spray corrosion. But the average reflectivity of the SiOxNy protected aluminum coating decreases about 2%, reach 88.6%, in the band 400nm-2500nm.
© (2014) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Wenjun Pei and Hongxiang Liu "Study of inverted thermal evaporation for large mirror", Proc. SPIE 9280, 7th International Symposium on Advanced Optical Manufacturing and Testing Technologies: Large Mirrors and Telescopes, 92800H (2 September 2014); https://doi.org/10.1117/12.2068419
Advertisement
Advertisement
RIGHTS & PERMISSIONS
Get copyright permission  Get copyright permission on Copyright Marketplace
KEYWORDS
Aluminum

Coating

Reflectivity

Mirrors

Nitrogen

Oxygen

Tungsten

RELATED CONTENT


Back to Top