Optical motion control applied to the Atmospheric Cloud Physics Laboratory /ACPL/

The use of laser radiation pressure for optical motion control (OMC) of water droplets (5-130 micron radius) is discussed. It is shown that a Gaussian beam can be used to manipulate and stabilize individual particles for studying cloud droplet or ice crystal growth and for investigating collision/coalescence phenomena. In the near-zero-G environment of the Atmospheric Cloud Physics Laboratory (ACPL) payload on Shuttle/Spacelab, OMC can provide: (1) velocities from less than 0.01 to 5 cm/sec; (2) precise positioning (+ or - 5 microns) of water droplets up to 130 microns; (3) simulation of 1-g conditions (velocity or acceleration) for droplets of up to about 13 microns. ACPL experiments benefiting from OMC are also discussed.