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

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 w hich based on temperatureconstant substrate assumption is not efficient any more. Therefore,an equivalent circuit model w as presented to analyze the thermal response characteristics of substrate-free FPA w ith electrics and holistic approach. According to this model,the thermal characteristics of substrate-free FPA under non-vacuum environment w ere analyzed. The result show s that,the substrate-free FPA has excellent infrared imaging performances under atmospheric pressure,w hile its NETD( noise equivalent temperature difference) is just increased several times than in the vacuum environment.