Detection of nitrogen dioxide using a room temperature operation mid-infrared InSb light emitting diode

The authors report trace gas detection of nitrogen dioxide (NO/sub 2/) using a room temperature operation InSb LED and an infrared absorption technique. A gas growth characteristic has been obtained for an 11 cm long gas cell containing a light pipe for light collection and transmission. The results show that detection of NO/sub 2/ at a concentration level of 10 ppm can be achieved in this sensor design.