Herzog William D, Tysk Shane M, Tardiff David W, Cappiello Gregory G, Jong Jason M, Jeys Thomas H, Hoffeld Ronald H, Sanchez Antonio, Daneu Vincenzo
Lincoln Laboratory, Massachusetts Institute of Technology, Lexington, Massachusetts 02420, USA.
Appl Opt. 2007 Jun 1;46(16):3150-5. doi: 10.1364/ao.46.003150.
What is believed to be a new concept for the measurement of micrometer-sized particle trajectories in an inlet air stream is introduced. The technique uses a light source and a mask to generate a spatial pattern of light within a volume in space. Particles traverse the illumination volume and elastically scatter light to a photodetector where the signal is recorded in time. The detected scattering waveform is decoded to find the particle trajectory. A design is presented for the structured laser beam, and the accuracy of the technique in determining particle position is demonstrated. It is also demonstrated that the structured laser beam can be used to measure and then correct for the spatially dependent instrument-response function of an optical-scattering-based particle-sizing system for aerosols.
