Protective coatings for FUV to NIR advanced telescope mirrors
Abstract
The NASA Cosmic Origins Program Annual Technology Report of Oct 2011 defined the goal for the “Development of UV coatings with high reflectivity (>90-95%), high uniformity (<1-0.1%), and wide bandpasses 100 nm to 300-1000 nm)”. We address this goal by exploring applicable materials and processes to produce protected aluminum mirror coatings that will satisfy the needs of future space telescope systems of interest to NASA and the astrophysics community. Void-free thin films of absorption-free materials are required to protect and maintain high reflectivity and durability of aluminum mirrors in laboratory and pre-launch environments. Precisely controllable and scalable deposition process is also required to produce such coatings on large telescope mirrors. In this report, we present our preliminary experimental studies on various fluoride coatings by conventional coating techniques. MgF2 coating by Atomic Layer Deposition (ALD), a promising technique, is also presented. Spectrophotometric and ellipsometric measurements of the optical properties of these coatings are reported.
- Publication:
-
American Astronomical Society Meeting Abstracts #223
- Pub Date:
- January 2014
- Bibcode:
- 2014AAS...22334402B