A graphic image depicting a laser comb measuring the light absorption patterns of carbon dioxide molecules. Source: Sarah Scholten, University of Adelaide
A new laser-based system engineered at the University of Adelaide, Australia, provides real-time, accurate measurements of gas properties. Researchers compare the ability of the optical frequency comb tool to distinguish between different gas compounds in a sample to the sensitive nose of a bloodhound.
The device generates millions of different light frequencies, which are passed through a gas sample. As each gas molecule absorbs a distinctive set of frequencies or colors, a unique fingerprint of the sample composition is indicated by the pattern of light absorption. The technique was demonstrated by measuring the number density of carbon dioxide with an accuracy of better than one percent and a precision of 0.04 percent in a measurement and analysis cycle of less than one second.
Applications in environmental monitoring and detection of industrial contamination are envisioned. Its use in analyzing the chemical composition of the exhaled breath as a screening tool for diagnosing various diseases will also be evaluated by the research team.
