The mid-infrared spectral region has been a subject of tremendous interest as the practical realization of optoelectronic devices operating in the 2-5 µm wavelength range provides potential applications in an extensive range of fields.
The mid-infrared contains the fundamental fingerprint absorption bands of several pollutant and toxic liquids and gases including CO (4.6 µm), CO2 (4.2 µm), and methane (3.3 µm), which require accurate, in situ multi-component monitoring in various different circumstances (coal mines, oil-rigs, car exhausts , landfill sites) and in concentrations, ranging from ppb to nearly 100%.
The mid-infrared also offers unique fingerprints with strong absorption bands for pharmaceuticals, drug intermediates, bio-chemicals, and narcotics enabling highly selective and sensitive imaging or detection. Therefore, the mid-infrared has generated plenty of interest for the development of sensitive optical sensor instrumentation.
By using diode lasers or LEDs tuned to these key absorption bands, one can readily envisage highly sensitive and gas specific sensors that are based on optical absorption.
Spectrum of 4.6 µm LED measured with Bentham TMc300-based IR spectroradiometer
(Images and application information courtesy of Dr Peter Carrington, University of Lancaster)
This information has been sourced, reviewed and adapted from materials provided by Bentham Instruments Limited.
For more information on this source, please visit Bentham Instruments Limited.