Effects of Phosphor Persistence on High-Speed Imaging of Transient Luminous Events

Wednesday, 17 December 2014
Jianqi Qin, Penn State University, University Park, PA, United States, Victor P Pasko, Penn State Univ, University Park, PA, United States, Sebastien J Celestin, CNRS - LPCE, Orleans Cedex 2, France, Steven A Cummer, Duke University, Electrical and Computer Engineering Department, Durham, NC, United States, Matthew G McHarg, United States Air Force Academy, Department of Physics, Colorado Springs, CO, United States and H C Stenbaek-Nielsen, University of Alaska Fairbanks, Geophysical Institute, Fairbanks, AK, United States
High-speed intensified cameras are commonly used to observe and study the transient luminous events known as sprite halos and sprite streamers occurring in the Earth's upper atmosphere in association with thunderstorm activity. In such observations the phosphor persistence in the image intensifier, depending on its characteristic decay time, might lead to a significant distortion of the optical signals recorded by those cameras. In the present work, we analyze observational data obtained using different camera systems to discuss the effects of phosphor persistence on high-speed video observations of sprites, and introduce a deconvolution technique to effectively reduce such effects. The discussed technique could also be used to enhance the high-speed images of other transient optical phenomena in the case when the phosphor persistence has a characteristic decay time that is comparable to the temporal resolution of the cameras required to resolve the phenomena.