Description: In Phase I we demonstrated each aspect required for design and fabrication of Lyot Stops and Apodization Masks for use in a coronagraphic instrument and delivered working components to collaborators at NASA and the Space Telescope Science Institute for evaluation. The technical achievements included: 1) first high quality mirror with carbon nanotubes 2) First nanotubes grown on metallic coatings 3) Dark patterned carbon nanotubes with micron-scaled features. During Phase II we will work with the NASA and STScI collaborators to determine how to improve these components and deliver second generation components to extend the performance of the STScI test bed in support of implementation on future NASA missions such as HABEX or UVOIRS. In addition we will work with NASA collaborators to design and fabricate carbon nanotube coated Lyot Stops for the Visible Nulling Coronagraph (VNC) test bed, also of key importance to the decadal missions referenced above. Lastly, we plan to collaborate with the LISA telescope team at NASA GSFC to design and fabricate a carbon nanotube apodization mask on a powered secondary mirror that could be used in single crystal silicon telescope as a pathfinder for LISA. One of the technical goals of Phase II are to pattern more complex Lyot Stop geometries while maintaining geometrical accuracy through the nanotube growth process. Further optimization of the apodization masks for coronagrahic use include: 1) increasing the metallic coating reflectance to near ideal 2) optimization of the nanotube darkness on the metallic coatings 3) greyscale patterning of carbon nanotubes and medium reflectance coatings on the mirrors to achieve enhanced diffraction suppression. For the LISA telescope diffraction spoiler application we will demonstrate patterning and growth of carbon nanotubes at the micron scale which when combined with metallic nanostructures can provide enhanced field suppression; another enabling technology to NASA missions.

Benefits: Stray-light and diffraction suppression is critical to NASA instrumentation because it improves signal to noise and observational efficiency in high contrast regions present in Earth, solar and coronagraphic applications. The PI and ANP/LC have delivered a large variety of instrument components including, baffles, stops, tubes and beam dumps. Development of a process compatible with reflective coatings and high quality optics for this SBIR, will enable an entirely new class of components and instrumentation for scientific observations. NASA requires calibrators for all manner of instruments to allow scientific data to be of the highest accuracy. On-mirror diffraction suppression is enabling for e-LISA as the telescope is used in duplex and requires extreme suppression of the the high power transmitted beam. This is also a challenge in Laser Communications and of great interest to NASA that will be addressed by this SBIR. Carbon nanotubes have the highest emissivity ever measured and arenearly ideal in this respect. We expect that further enhancement of the rob ustness of carbon nanotube coatings demonstrated in this SBIR will result in the use of this technology on more NASA instruments. The PI has built and tested carbon nanotube absorber thermal detectors with superconducting transition edge detectors; a modified CVD process will make the use of carbon nanotube absorbers compatible with more detector technologies.

During Phase I of this SBIR we developed coatings and chemical vapor deposition processes compatible with high surface quality single crystal silicon mirrors. Phase II will continue optimization of these optical components for NASA and commercial use. We believe that this technology can be applied to autonomous vehicle imaging where stringent stray light control is required to enable robust operation in challenging lighting conditions. In addition, success during Phase I has initiated collaborative efforts with the Swatch group, who are interested in patterning nanotubes on gold or silver coated substrates for high end watches. Advanced Nanophotonics, Inc. is also collaborating with the technical arm of Universal Studios to deliver samples of ultradark nanotube coatings for use in special effects.