This article presents design issues of high-sensitive laser absorption spectroscopy systems for nitrogen oxides (NO(x)) detection. Examples of our systems and their investigation results are also described. The constructed systems use one of the most sensitive methods, cavity enhanced absorption spectroscopy (CEAS). They operate at different wavelength… (More)
The paper presents one of the laser absorption spectroscopy techniques as an effective tool for sensitive analysis of trace gas species in human breath. Characterization of nitric oxide, carbonyl sulphide and ethane, and the selection of their absorption lines are described. Experiments with some biomarkers showed that detection of pathogenic changes at the… (More)
A silicon integrated circuit is reported for radiating picosecond pulses with tunable repetition rate, covering frequencies from 0.03 to 1.03 THz. This source is used in a gas spectroscopy setup to measure the absorption lines of ammonia and water in the terahertz region.