Presentation + Paper
15 May 2017 Study of performance loss of Lyman alpha filters due to chemical contamination
Author Affiliations +
Abstract
Observations in the UV and EUV allow many diagnostics of the outer layers of the stars and the Sun so that more and more space telescopes are developed to operate in this fundamental spectral range. However, absorption by residual contaminants coming from polymers outgassing causes critical effects such as loss of signal, spectral shifts, stray light… Thus, a cleanliness and contamination control plan has to be defined to mitigate the risk of damage of sensitive surfaces. In order to specify acceptable cleanliness levels, it is paramount to improve our knowledge and understanding of contamination effects, especially in the UV/EUV range. Therefore, an experimental study has been carried out in collaboration between CNES and IAS, in the frame of the development of the Extreme UV Imager suite for the ESA Solar Orbiter mission; this instrument consists of two High Resolution Imagers and one Full Sun Imager designed for narrow pass-band EUV imaging of the solar corona, and thus very sensitive to contamination. Here, we describe recent results of performance loss measured on representative optical samples. Six narrow pass-band filters, with a multilayer coating designed to select the solar Lyman Alpha emission ray, were contaminated with different amounts of typical chemical species. The transmittance spectra were measured between 100 and 200 nm under high vacuum on the SOLEIL synchrotron beam line. They were compared before and after contamination, and also after a long exposure of the contaminated area to EUV-visible radiations.
Conference Presentation
© (2017) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Delphine Faye, Xueyan Zhang, Pierre Etcheto, and Frédéric Auchère "Study of performance loss of Lyman alpha filters due to chemical contamination", Proc. SPIE 10236, Damage to VUV, EUV, and X-ray Optics VI, 102360F (15 May 2017); https://doi.org/10.1117/12.2265864
Advertisement
Advertisement
RIGHTS & PERMISSIONS
Get copyright permission  Get copyright permission on Copyright Marketplace
KEYWORDS
Contamination

Imaging systems

Optical filters

Extreme ultraviolet

Solar processes

Sun

Ultraviolet radiation

RELATED CONTENT

The STEREO SECCHI/EUVI EUV coronal imager
Proceedings of SPIE (September 12 2007)
The Extreme Ultraviolet Explorer
Proceedings of SPIE (November 09 1981)

Back to Top