A low cost MWIR thermal imaging line scanner based on a multiplexed PbSe FPA has been developed. It was designed to be mounted on the underside of UAVs to remotely map battlefields. It also has many dual-use commercial applications. The first unit has been tested in the laboratory and in roof-top imaging demonstrations. It has produced excellent imagery. The noise equivalent temperature difference has been measured to be 0.55 C in preliminary tests. An improved FPA will be installed soon in the unit which will significantly reduce the NET.
This paper discusses the successful demonstration of a first in thermal imaging with utilized an inexpensive midwavelength IR (MWIR) linear, focal plane assembly (FPA) comprising a long linear array of lead selenide (PbSe) photoconductors interfaced to an on-focal-plane multiplexer (MUX). The design of this unique IR sensor consisted of a rugged dewar package in which was mounted a reliable, solid state thermoelectric cooler (TEC) coupled with the proven technologies of both the PbSe fabrication process and the complementary metal-oxide- semiconductor (CMOS) multiplexers. This combination of components now provides the system designer with a readily available, cost-effective, second-generation PbSe focal plane assembly for scanning, thermal imaging applications that require high resolution and system performance of NE(Delta) T capability of better than 0.2 degree(s)C.