Standoff detection of biological aerosols by UV-laser induced fluorescence

This report describes the experimental biolidar developed at FFI during the period 2005-2007 to detect biological aerosols. The biolidar is based on ultraviolet laser induced fluorescence, in which ultraviolet light is used to induce fluorescence in aerosols. It turns out that aerosols with biological content emit fluorescence when excited at certain wavelengths, e.g. 355 nm, which was used in this work, and this can be used to distinguish biological aerosols from other aerosols. The biolidar was built with commercially available components, and in the initial lidar design described here, also commercial software for data acquisition was used. In the design of the lidar, it was chosen to keep the elements simple and – if possible – with better performance than expected necessary. This way it will be possible to reduce the performance of the lidar artificially to get an estimate of the performance needed in a final design. The design of the lidar is described and explained, and initial results are shown.