Abstract

A transparent electromagnetic shield to protect solar panels and the like from dust deposition. The shield is a panel of clear non-conducting (dielectric) material with embedded parallel electrodes. The panel is coated with a semiconducting film. Desirably the electrodes are transparent. The electrodes are connected to a single-phase AC signal or to a multi-phase AC signal that produces a travelling electromagnetic wave. The electromagnetic field produced by the electrodes lifts dust particles away from the shield and repels charged particles. Deposited dust particles are removed when the electrodes are activated, regardless of the resistivity of the dust. Electrostatic charges on the panel are discharged by the semiconducting film. When used in conjunction with photovoltaic cells, the power for the device may be obtained from the cells themselves. For other surfaces, such as windshields, optical windows and the like, the power must be derived from an external source. One embodiment of the invention employs monitoring and detection devices to determine when the level of obscuration of the screen by dust has reached a threshold level requiring activation of the dust removal feature.

Other References

• Masuda, S. et al., Approximate Methods for Calculating a Non-Uniform Travelling Field, Journal of Electrostatics, 1 (1975), pp. 351-370, Elsevier Scientific Publishing Company, Amsterdam, The Netherlands.
• Masuda, S., Electric Curtain for Confinement and Transport of Charged Aerosol Particles, Albany Conference of Electrostatics—1971, Albany, New York, Jun. 8-11, 1971, Electrostatic Society of America, American Meteorological Society and Institute of Electrical and Electronics Engineers, The Annual General Meeting of Static Electrification Group—1971, London, UK, Oct. 13, 1971, The Institute of Physics and The Physical Society, pp. 1-27 and title page.