A new optical particle counter was developed to provide fast in situ sizing of cloud droplets in the Leipzig Aerosol and Cloud Interaction Simulator (LACIS). The new instrument features white light for the illumination of the sampling volume: two off-axis elliptical mirrors, providing a wide angle of collection for light scattered by particles; and an optically defined sampling volume. The smooth unambiguous response characteristic for water droplets allows direct conversion of the measured signal amplitudes into droplet diameters. Preliminary response measurements for dry polystyrol microspheres and water droplets, grown in the LACIS on NaCl particles, have shown good agreement with the corresponding calculated response curves.
© 2005 Optical Society of America
(010.1100) Atmospheric and oceanic optics : Aerosol detection
(120.4570) Instrumentation, measurement, and metrology : Optical design of instruments
(290.1090) Scattering : Aerosol and cloud effects
(290.4020) Scattering : Mie theory
(290.5850) Scattering : Scattering, particles
Alexei Kiselev, Heike Wex, Frank Stratmann, Alexandre Nadeev, and Dmitry Karpushenko, "White-light optical particle spectrometer for in situ measurements of condensational growth of aerosol particles," Appl. Opt. 44, 4693-4701 (2005)