The thermopile detector package (TP

The thermopile detector package (TPS 333) contains a thermistor,
which acts as a compensating detector in order to overcome the
set up and environmental related errors. D* of the TPS 333 is 0.6 ×
108 (cm ×
√
Hz)/W and the DC sensitivity 35 V/W. The two analog
signals measured from the thermopile detector – namely, the thermistor
and thermopile signals – were coupled to a measurement
card (National Instruments 6210) USB bus version equipped with
eight differential channels with 16-bit AD converters. Labviewbased
user interface and measurement software were installed in
a PC environment. The sensor system was calibrated by varying
the temperature of the blackened aluminium plate placed on top
of a Peltier element at room temperature. The sensor optics was
placed 10–12mm from the target, which totally covered the sensor’s
FOV. The temperature reference of the aluminium target was
measured with a thermistor (Shibaura PSB-S7-PB7-43) attached to
the measurement plate.