Isaac Scientific Publishing

Journal of Advances in Applied Physics

A New Instrument for Determining Charge to Diameter Distributions of Charged Particles

Download PDF (5010.7 KB) PP. 35 - 42 Pub. Date: November 30, 2019

DOI: 10.22606/jaap.2019.11003


  • James H. Anderson*
    SUNY Empire State College, Genesee Valley Learning Center, 680 Westfall Rd.. Rochester, NY 14620, USA


A new instrument for measuring the charge-to-diameter ratio of small particles (2-100 μm) is described. In this instrument, the terminal velocity of charged particles in an electric field in air is determined by measuring the time of flight of the particles between two laser beams. The main advantages of this instrument are that it is easy to operate, and only about 15 min. are required to obtain a distribution of charge-to-diameter ratio for a few thousand particles. The major disadvantage is that low charged and uncharged particles cannot be detected.


Particle charge, charge distribution, q/d distribution, triboelectricty, tribocharging, elecrophotographic toners.


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