The Air Force requires lightweight, stiff and stable mirrors for use in high quality, air-based and space-based observation and energy projection systems. The current state-of-the-art uses various types of honeycomb materials with glass and composite face sheets that are expensive to fabricate. Current replicated mirror technologies do not meet the stringent performance parameters of both light weight and surface quality. Nanolaminates pucker locally when bonded to SiC and stretched shell mirrors cannot maintain their shape without significant supporting structures. The results are structurally inefficient mirror systems that cost and weigh too much. The proposed program will develop low cost manufacturing methods for reflective films supported by a structural network of lightweight nanotubes. The Replicated Nanotube Reflector (RNR) uses a low cost sputtered film rather than a nanolaminate and a low cost mixed grade of nanotubes as a supporting structure. Testing has already shown that this combination can produce a surface roughness of only 8.1Å, exceeding the stated λ/500 goal. ABS will develop the RNR system through a careful plan of technology transfer, design, modeling, and prototype manufacture and testing. Complete development of this technology will provide a mirror system that will enable better, lighter, and less expensive optical instruments.
Benefit: In addition to the myriad of Air Force, Missile Defense Agency, NASA and other government missions such as ABL, SBL and observation platforms that would take advantage of extremely stiff and lightweight mirrors, many university and private observatories would be ready customers of the RNR mirror technology. UAVs in particular use both curved focusing mirrors and flat steering mirrors to rapidly image over tactical battlespaces. ABS commercialization partner, QinetiQ, is the developer of the Zephyr. This extremely high altitude UAV is very payload weight limited and would benefit greatly from a low cost, lightweight set of concentrating and steering mirrors.
Keywords: Low Cost, Lightweight, Nanotube Sputtered Film Mirror
