Abstract: trodynamic levitator-trap (Paul trap) is used at line frequency (i.e. 60 Hz) as a sample cell for the long term microphotography of a microparticle in air at STP. Images are obtained in a trap modified to eliminate stray static fields at its AC 'null' point. Resolution in these long term images is found to be limited principally by stochastic thermal fluctuations and optical diffraction. A stochastic differential equation constructed for describing the particle's motion is found to be in good agreement with imaging experiments. This model provides an optimal limit to which a particle may be localized by increasing the drive potential, and indicates that this limit is a function principally of particle size and temperature. Images taken in fluorescence from a glycerol particle containing a probable surfactant are presented. Polarization resolution of these images clearly shows segregation of the molecule to the surface and identifies the orientation of the molecular emission moment in relation to the surface normal.!8
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