Use of pump current modulation of diode laser for increased sensitivity of detection of 13СO2 in human exhaled breath. (9th February 2018)

• Record Type: Journal Article
• Authors: Kireev, S V; Kondrashov, A A; Shnyrev, S L; Safagaraev, A P
• Is Part Of: Laser physics letters. Volume 15:Number 3(2018:Mar.)
• Publication Date: 2018-02-09
• Subjects: carbon dioxide -- absorption spectroscopy -- current modulation; Lasers -- Periodicals; Physics -- Periodicals; 621.366
• DOI: 10.1088/1612-202X/aa9da0
• Languages: English
• ISSNs: 1612-2011

Abstract

Abstract: This paper reports that the use of a lock-in detection technique, when the pump current modulation of a diode laser is operating near the wavelength of 2 µ m, allows the improvement of the sensitivity of the online detection of 13 СO2 in expired air by more than three orders of magnitude. The sensitivity of the 13 СO2 detected in the paper is 60 ppb with an error of 13 СO2 concentration measured in the exhaled breath at the level of 2.9% for an optical path length of 60 cm.