Absorption spectroscopy based sensor for oxygen detection

Abstract

The purpose of this study is to describe a development of a spectroscopy-based sensor used for detecting oxygen in the UV region between 200-230 nm. There are some traditional sensors that were introduced and experimented in past years, but all of them had some disadvantages. Demonstrated here is basically an open-path single pass sensor that is ultra-sensitive, susceptible to cross sensitivity, able to withstand a harsh environment, able to be used for long life and also low-cost to fabricate. Beer-Lambert’s law is used for calculations resulting in finding an optimized path length of 9.55 cm and non-optimized lengths of 7.8 cm and 12.3 cm to detect oxygen in the desired concentration range. Zemax program has been used to model and optimize the sensor to find the sensor’s structure and dimensions, the best structure is the CPC. Then Spectralcalc.com is used to simulate the sensor in order to analyse sensitivity of the sensor using transmittance vs wavelength diagrams in different concentration ranges and the highest sensitivity was for 12.33 cm sensor (-1.863187935602 × 10-9).