Laser Breathalyzer – ETHYLAS

The ETHYLAS project aims at the development of an innovative breathalyzer using a laser source. This sensor will be based on an optical technique using new generation light source, emitting a wide spectral range in the mid-infrared domain. Optical gas sensors are already a part of our modern society and offer undeniable advantages over current sensors like chemical ones: sensitivity, selectivity, robustness, calibration free, accuracy, … However, precision gas sensors currently available are usually bulky, complex and have an expensive operating cost. The down-sizing of the optical gas sensors and the decrease of their cost are the main way for a full-scale deployment.
Chemical breathalyzers are unreliable and do not provide a quantitative measure of alcohol content. The chemical compounds contained in these devices gradually degrade in time. The electronic models use an oxidation chemical reaction that cannot discriminate ethanol. In addition, they are easily contaminated and require regular calibration. Infrared breathalyzers are not wavelength selective despite the use of filters. They are sensitive to interferers and need to be regularly calibrated.
ETHYLAS project will create a small-scale, reliable and accurate breathalyzer. It will be based on the tunable laser absorption spectroscopy in the mid-infrared domain. A widely tunable quantum cascade laser will be injected in a compact multi-pass cell to identify the ethanol molecule and measure its concentration in the exhaled air. Unlike current breathalyzer, ETHYLAS will provide an absolute concentration measurement without any calibration process.