Mid-IR fibre optics spectroscopy in the 3300-600 cm−1 range

The latest development in IR fibre optics enables to expand spectral range of process spectroscopy from 3300 to 600 cm−1. Mid-IR wavelength range from 5000 to 1700-1000 cm−1may be covered by chalcogenide IR glass (CIR) fibres while polycrystalline infrared (PIR) fibres made of silver halides solid solutions transmit radiation of the whole most informative “finger-print” part of the spectrum from 3300 to 600 cm−1. PIR fibre based immersion ATR probes had been manufactured and successfully tested with FTIR spectrometers in the field of remote spectroscopy of chemical reaction and fuel analysis. The sensitivity of different ATR elements, performance and permanence of the probes are considered in temperature range 20-150 °C.