Hyperspectral Compressive Imager Based on a Tandem SWIR Tunable Fabry-Perot Filter

A need exists for an electronically tunable hyperspectral sensor that operates over the 2.3-2.5 m spectral range with spectral resolution approaching 0.1 nm. A hyperspectral sensor that achieves these specifications will a.) advance short wave infrared hyperspectral imaging beyond current pushbroom acquisition sensors and b.) enable remote detection and identification of chemicals associated with nuclear proliferation activities. • General statement of how this problem is being addressed. A narrow bandpass sensor operating in the shortwave infrared will be developed by integrating an electronically tunable tandem Fabry-Perot etalon with a compressive sensing module and an automated Adaptive Cosine Estimation detection algorithm. The tandem etalon design will enable the sensor to achieve the desired high spectral resolution and spectral range while enabling spectral agility (i.e. the ability to select key spectral resolution elements within the spectral range). The primary motivation for applying compressive sensing is to eliminate the high-cost focal plane array required by traditional hyperspectral imaging systems operating in the SWIR. In addition, spatial compression using the DMD enables dynamic control of the sensor’s field-of-view as well as spatial resolution. • What is to be done in Phase I? Under the Phase I program a system model will be generated and a breadboard system will be designed, built, and tested. The compressive sensing basis set and preliminary reconstruction algorithms will be demonstrated. The Phase I will also produce requirements and a conceptual design for a prototype instrument to be fully developed under a Phase II effort. • Commercial Applications and Other Benefits. Applications include airborne or mobile ground based surveillance of process streams indicative of radiological, nuclear, and chemical agent manufacturing activities. This system could also serve a broader range of airborne surveillance activities. The proposed solution could be widely adopted for homeland security applications, for example, monitoring large public venues such as stadiums, auditoriums, public transportation, etc. This system could be used in the commercial sector for toxic industrial chemical detection and process monitoring. • Key Words. Tunable Filter, Fabry-Perot Etalon, Hyperspectral Sensing, Compressive Sensing • Summary for Members of Congress. Shortwave infrared hyperspectral imaging sensors are sought for monitoring activities associated with nuclear and radiological material production. A highly sensitive yet low-cost and ruggedized compressive sensing hyperspectral imager solution is proposed to meet this need.