Impact analysis of longwave infrared focal plane array (LWIR FPA) temperature variations on its characterization process

Abstract

Characterizing Longwave Infrared Focal Plane Arrays (LWIR FPA) is a fundamental task with significant implications for broad applications in industrial and research and development (R&D) domains. Prior research has deliberated upon the selection of reference temperatures, integration time, and frame rate. This work is based on that knowledge and squarely centered on analyzing the overall FPA performance according to its internal temperature. In this context, the operability, uniformity, signal transfer function (SiTF), and noise equivalent temperature difference (NETD) were evaluated. The results indicated a degradation of performance of LWIR FPA with the increase in bad pixel count, which led the operability to an abrupt decrease from approximately 99.5% to 39.4% and the uniformity of the LWIR FPA to fall markedly from 95.9% to 66.2% as the temperature increases. Similarly, under an f/1 aperture, the NETD results showed a value oscillation with an increasing trend, ranging from 32 to 41mK. In summation, this work exposes the need for a meticulous parameter selection for the characterization of LWIR FPA, which can impact both industrial and R&D contexts. Our results affirm our previous research, pointed the best results taking the reference temperatures of 25°C and 60°C. This effort significantly enhances our understanding of LWIR FPA, offering insightful guidance for future characterization practices.