DARPA Starts Curved IR Imagers Program

DARPA FOcal arrays for Curved Infrared Imagers (FOCII) program is created to expand upon the current commercial trend for visible sensor arrays by extending the capability to both large and medium format midwave (MWIR) and/or longwave (LWIR) infrared detectors. The program seeks to develop and demonstrate technologies for curving existing state-of-the-art large format, high performance IR FPAs to a small radius of curvature (ROC) to maximize performance, as well as curve smaller format FPAs to an extreme ROC to enable the smallest form factors possible while maintaining exquisite performance.

FOCII will address this challenge through two approaches to fabricating a curved FPA. The first involves curving existing state-of-the-art FPAs, while keeping the underlying design intact. The focus of the research will be on achieving significant performance improvements over existing, flat FPAs, with a target radius of curvature of 70mm. The fundamental challenge researchers will work to address within this approach is to mitigate the mechanical strain created by curving the FPGA, particularly in silicon, which is very brittle.

The second approach will focus on achieving an extreme ROC of 12.5 mm to enable a transformative reduction in the size and weight compared to current imagers. Unlike the first approach, researchers will explore possible modifications to the underlying design, including physical modifications to the silicon that could relieve or eliminate stress on the material and allow for creating the desired curvature in a smaller sized FPA. This approach will also require new methods to counter the effects of any modifications during image reconstruction in the underlying ROIC algorithm.

Thanks to TL for the link!