Anti-reflective Nanowire Coatings for IR Optics

Nano Terra proposes a novel approach utilizing nanowires to decrease the retroreflectivity of night vision systems. We will develop nanowire GRIN coatings for IR optics and, in particular, germanium windows. The coatings will minimize or eliminate retroflection at visible wavelengths, preserve or improve transmission in the infrared regions, and will be durable enough for field use. By applying nanowires in carefully tailored layers, we will not only form a graded index of refraction structure to reduce reflection but also form a protective layer, but also. Each successive layer of nanowires will be less dense than the previous layers, thus effectively decreasing the index of refraction with each layer, gradually reducing the index of refraction from that of the underlying substrate to that of air. We will explore novel methods for producing Si and Ge nanowire GRINs and will scale up the process. In addition multifunctional coatings will be demonstrated, such as a durable antireflective coating that also provides EMI shielding. Nano Terra is qualified to lead this effort because its staff has vast and unique experience in fabricating and precisely placing nanowires, and is a world leader in nano-scale manufacturing.