Active THz imaging and explosive detection with uncooled antenna-coupled microbolometer arrays

Abstract

Spectral signatures of solid materials in the THz range can provide spectroscopic information for chemical identification. Previously we have demonstrated the absorption coefficient extraction by scanned imaging of QCL THz beams attenuated through explosive samples. The detection was achieved by a unique pixel addressed within an uncooled antenna-coupled microbolometer 160x120 array specifically designed for the 1-5 THz range. This detector technology developed at CEA-LETI relies on amorphous silicon bolometer know-how and aims at opening the way to real-time video rate, with potential low cost. We report complementary tests of imaging in reflection configuration and the first tests of a second prototype where 320x240 bolometers are monolithically processed above a CMOS read-out circuit.