Equivalent circuit model of the substrate-free focal plane array based on the optical readout uncooled infrared imaging system

Abstract

与传统的有基底FPA(焦平面阵列)相比, 基于全镂空支撑框架结构的新型无基底FPA在热学特性上存在显著差异, 传统的基于恒温基底假设的热学分析模型不再适用, 因此, 通过电学比拟方法, 将无基底FPA的热响应特性等效为电学模型.通过该模型, 进一步分析了无基底FPA在非真空环境下的热学性能, 分析表明: 该无基底FPA具有在大气压下优良的红外成像性能, 其NETD(噪声等效温度差)值仅比真空环境下增加了数倍.;Thermal characteristics of new substrate-free FPA (focal plane array) with full hollow supporting frame structure are very different from that of traditional substrate FPA. The thermal analysis model which based on temperature-constant substrate assumption is not efficient any more. Therefore, an equivalent circuit model was presented to analyze the thermal response characteristics of substrate-free FPA with electrics and holistic approach. According to this model, the thermal characteristics of substrate-free FPA under non-vacuum environment were analyzed. The result shows that, the substrate-free FPA has excellent infrared imaging performances under atmospheric pressure, while its NETD (noise equivalent temperature difference) is just increased several times than in the vacuum environment.