Remote photoacoustic detection of liquid contamination of a surface

Perrett, B; Harris, M; Pearson, GN; Willetts, DV; Pitter, MC

Abstract

A method for the remote detection and identification of liquid chemicals at ranges of tens of meters is presented. The technique uses pulsed indirect photoacoustic spectroscopy in the 10-μm wavelength region. Enhanced sensitivity is brought about by three main system developments: (1) increased laser-pulse energy (150 μJ/pulse), leading to increased strength of the generated photoacoustic signal; (2) increased microphone sensitivity and improved directionality by the use of a 60-cm-diameter parabolic dish; and (3) signal processing that allows improved discrimination of the signal from noise levels through prior knowledge of the pulse shape and pulse-repetition frequency. The practical aspects of applying the technique in a field environment are briefly examined, and possible applications of this technique are discussed.

Citation

Perrett, B., Harris, M., Pearson, G., Willetts, D., & Pitter, M. (2003). Remote photoacoustic detection of liquid contamination of a surface. Applied Optics, 42(24), 4901-4908. https://doi.org/10.1364/AO.42.004901

• Journal Article Type: Article
• Publication Date: Aug 20, 2003
• Deposit Date: Oct 9, 2007
• Journal: Applied Optics
• Print ISSN: 1559-128X
• Publisher: Optical Society of America
• Peer Reviewed: Peer Reviewed
• Volume: 42
• Issue: 24
• Pages: 4901-4908
• DOI: https://doi.org/10.1364/AO.42.004901
• Publisher URL: http://dx.doi.org/10.1364/AO.42.004901