Robust Broadband Anti-Reflection Coating for Infrared Spectrum

This Small Business Innovation Research Phase I project seeks to develop a robust anti-reflection coating in mid-wavelength infrared (MWIR) spectrum. Such coating can virtually eliminate the Fresnel reflection over a broad spectrum range. The coating is enabled by the nano-technology, and can have large laser damage threshold. The combination of the optical function of the coating and its resistance to laser damage will enable a robust optical coating for high power laser applications. The technology can also be applied to other robust optical coating fabrication, such as highly reflective and partially reflective coatings. The combination of the material innovation and coating structure innovation will enable such novel optical coating technology. The intellectual merit mainly lies in technical challenges for coating design and material fabrication. BENEFIT: The availability of robust optical coating will be extremely beneficial to high power laser application, not only in MWIR spectrum but also in other spectra as well. High power laser devices and components are interest for many applications, in both of military field and non-military field. However, laser device or component failure caused by optical coating failure has caused the reliability concern for current state-of-art coating technology. The proposed robust optical coating using nano-technology can significantly enhance the robustness and reliability of the coating itself under the harsh environment, such as high laser power and high humidity. Also, it can enable novel optical function that conventional coating cannot achieve. The stability and the reliability of the high power laser devices and components can be drastically enhanced with the proposed coatings. Hence the new applications involved with stable high power lasers can be enabled.