High-Efficiency, Large-Area Curved Diffraction Gratings for Remote Sensing Applications in the Infrared

Infrared detection systems play a key role in national security, where they are used in aerial and satellite reconnaissance to identify potential targets and detect enemy weapons. While multispectral infrared imaging systems have greatly enhanced remotesensing capabilities, current systems have been optimized for the visible and shortwave infrared. Longwave infrared detection would also be of great benefit, but extending this technology to the longwave region requires the development of new curvedgrating fabrication techniques. In this program, we will develop a novel process for fabricating large-area diffraction gratings on curved surfaces. This process will exploit a unique curved-surface projection lithography technology that has been developedat Anvik. This technology will enable high-throughput fabrication of large-area curved diffraction gratings for applications in the long wave infrared. Anvik's curved grating fabrication technology offers a number of advantages compared with currentlyavailable fabrication techniques, including the capability to pattern on substrates having large sags, up to 12 mm, and also the capability to pattern with high resolution, down to 1 ¿m. Additionally, it is a high-throughput projection lithographytechnique, and is therefore suitable for large-scale production. Anvik's curved diffraction grating technology will lead to high performance gratings operating at long wave infrared wavelengths. This will enable the development of highspectral-resolution, compact, airborne remote sensing instrumentation serving the military and civilian sectors.