SPARCLE is an in situ aerosol photometer capable of determining both the particle size and refractive index. This is a new concept in aerosol measurement since most in situ measurement techniques are unable to fully characterize the measured particles. The work presented here is the calibration of the second generation of SPARCLE in measuring the angular distribution (phase function) of light scattered by a spherical particle with known size and refractive index.
The size and refractive index of spherical particles can be retrieved by comparing the measured phase functions with the theoretical phase functions. The theoretical phase function is calculated based on Mie theory.