A new methodology for reducing the NETD in LWIR imaging

The definition of parameters used for the LWIR FPA configuration plays a crucial role in determining the overall camera figures of merit (FOM), particularly the noise equivalent temperature difference (NETD), which measures the accuracy of detecting scene thermal deviations. The characterization of FOM significantly impacts on various applications, including industry, defense, and research and development (R&D). To minimize the NETD value, this study proposes a new methodology to evaluate and determine the optimal operating point of a commercial FPA with 17μm pitch amorphous silicon microbolometer pixels. In this process, sensor responses were analyzed for temperatures ranging from 15°C to 76°C, while the integration time (τ ), the compensation bolometer gate voltage (GSK) and the active bolometer gate voltage (GFID) were varied. The optimized NETD of 34.3mK shows the competitive advantage of the proposed method over 40.1mK obtained using the manufacturer’s recommended operating point. These results demonstrate the relevance and feasibility of the proposed methodology, as the performance of the LWIR FPA was significantly improved, and consequently, the system performance. Furthermore, this study guides future work on this topic, offering a path for further advancements in the characterization of FPA and optimization of the system.