Authors: J Joly P Ridoux J Hameury M Lièvre JR Filtz
Publish Date: 2008/04/23
Volume: 29, Issue: 3, Pages: 1094-1106
Abstract
In recent years there has been a growing demand to calibrate industrial blackbodies both at short wavelengths for lower temperatures and at long wavelengths for higher temperatures User requests cover a very wide temperature range from −20°C to 1500°C in the infrared bands used by thermal cameras or as defined by specific applications especially the 1–3 μm 3–5 μm and 8–12 μm bands Therefore LNE Laboratoire National de Métrologie et d’Essais has developed a radiance comparator with a mirrorbased optical system an associated set of interference filter wheels a modular holder for several infrared detectors and a lockin amplifier This setup is designed to be very versatile in terms of wavelength and temperature Targeted performances have a thermal resolution better than 005°C and a known and controlled sizeofsource effect SSE A silicon detector and a visibletonear infrared integrating sphere were used to assess the stray light inside the housing and supplementary baffles and stops were used to reduce it to an acceptable level The investigation included measurement of the SSE for this comparator layout Then the performance in the 3–5 μm and 8–12 μm bands using respectively indium antimonide InSb and mercury cadmium telluride MCT detectors was evaluated using a water heatpipe blackbody This paper describes the modeling and the technical solutions implemented to optimize the optical system Preliminary results are presented for the shortterm stability the thermal resolution between −20°C and 960°C and also the SSE up to 60 mm in these bands
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