Improved scene interpretability and detection in LWIR sensors via polarimetric filtering and NEDT mitigation techniques

This paper investigates the impact of integrating a pixelated polarimetric filter with a long-wave infrared (LWIR) focal plane array (FPA) on overall sensor performance. While adding the filter increases the noise-equivalent differential temperature (NEDT) due to reduced photon throughput in each polarization channel, this limitation is offset by improved target contrast enabled by polarimetric sensitivity. Results demonstrate that, despite higher NEDT, the enhanced signal-to-clutter ratio (SCR) achieved through combined polarimetric and thermal sensing improves scene interpretability and object detection. Furthermore, we present and evaluate processing algorithms that mitigate the NEDT increase, allowing the system to outperform conventional non-polarimetric sensors under relevant operating conditions.