desc-ription the tps 434 thermopile sensor in to 5 type housing employs a chip of 0.5 x 0.5 mm2 absorber size and a 30 k thermistor as temperature reference. the round window opening is equipped with a 5.5 mm longpass (standard) infrared filter. the sensor shows a flat sensitivity characteristic over the wavelength. the tps 434 can be equipped with a g9 (8 ... 14 m) filter for precision pyrometers (tps 434 g9).  features extremely small absorber size - for high precision pyrometers thermistor temperature reference included low temperature coefficient of sensitivity applications: ear thermometers and pyrometers