Chemical aerosol detection and identification using Raman scattering

Early warning of the presence of chemical agent aerosols is an important component in the defense against such agents. A Raman spectrometer has been constructed for the purpose of detecting and identifying chemical aerosols. We report the detection and identification of a low‐concentration chemical aerosol in atmospheric air using 532‐nm continuous wave laser Raman scattering. We have demonstrated the Raman scattering detection and identification of an aerosol of isovanillin of mass concentration of 1.8 ng/cm3 with a signal‐to‐noise ratio of about 19 in 30 s for the 1116‐cm−1 mode with a Raman cross section of 3.3 × 10−28 cm2 using 8‐W double‐pass laser power.