The CellaTemp® PX 35 has a very short-wave and narrow-band spectral sensitivity. Therefore, the pyrometer reacts much less to interferences such as signal attenuation by dust, steam or smoke in the pyrometer's field of view, to soiling of the protective screen or to emissivity fluctuations from the target than a conventional spectral pyrometer. Metals have the physical property that the emissivity increases with shorter radiation wavelengths and higher object temperatures. Therefore, the CellaTemp® PX 35 is ideal for precise measurement of metals and very hot objects. In addition, the pyrometer is used to measure thin semiconductors, as semiconductors have very good radiation properties in the pyrometer's special spectral range. For wavelengths > 1 μm, silicon is transparent, so a standard pyrometer would measure the temperature of the material behind it through the silicon.