Revolutionizing Thermal Imaging

Zubin Jacob, Elmore Professor at Purdue University’s Elmore Family School of Electrical and Computer Engineering, leads a team developing a new technology that uses meta-optical devices for thermal imaging. This innovation offers richer information about imaged objects, potentially expanding thermal imaging applications in autonomous navigation, security, medical imaging, and remote sensing.

“Our method overcomes the challenges of traditional spectral thermal imagers, which are often bulky and delicate due to their reliance on large filter wheels or interferometers,” Jacob explained. “We combined meta-optical devices with advanced computational imaging algorithms to create a compact, robust system with a large field of view.”

The research, published in Optica, describes a new spectro-polarimetric decomposition system using spinning metasurfaces to break down thermal light into its spectral and polarimetric components. This allows the system to capture detailed spectral and polarization information, alongside the intensity data from traditional thermal imaging.

The team demonstrated that their system could classify various materials using a commercial thermal camera, a task challenging for conventional thermal cameras. This ability to identify materials based on spectro-polarimetric signatures could enhance safety and efficiency in applications like autonomous navigation.

“Traditional autonomous navigation relies heavily on RGB cameras, which struggle in low light or bad weather,” said Xueji Wang, a postdoctoral researcher at Purdue. “Our spectro-polarimetric thermal camera can offer clearer images in these conditions, enhancing scene perception and safety.”

The researchers successfully used their system to spell out “Purdue” with materials having unique spectro-polarimetric properties, achieving a three-fold increase in material classification accuracy compared to traditional methods. They plan to improve the system’s spectral resolution, efficiency, and speed, and aim to extend its application to room-temperature imaging using enhanced materials and metasurface designs.