These electrified areas are then tested by sprinkling a mixture of powdered flowers of sulfur and red lead (Pb 3O 4 or lead tetroxide) onto the plate. This deposits stranded areas of charge onto the surface of the plate. This creates a sudden, small electrical discharge along the surface of the plate. A source of high voltage such as a Leyden jar (a type of capacitor) or a static electricity generator is applied to the needle, typically through a spark gap. The point is positioned very near or contacting the plate. Two-dimensional (2D) Lichtenberg figures can be produced by placing a sharp-pointed needle perpendicular to the surface of a non-conducting plate, such as of resin, ebonite, or glass. Although Lichtenberg only studied two-dimensional (2D) figures, modern high voltage researchers study 2D and 3D figures ( electrical trees) on, and within, insulating materials. This discovery was also the forerunner of the modern day science of plasma physics. By then pressing blank sheets of paper onto these patterns, Lichtenberg was able to transfer and record these images, thereby discovering the basic principle of modern xerography. After discharging a high voltage point to the surface of an insulator, he recorded the resulting radial patterns by sprinkling various powdered materials onto the surface. In 1777, Lichtenberg built a large electrophorus to generate high voltage static electricity through induction. When they were first discovered, it was thought that their characteristic shapes might help to reveal the nature of positive and negative electric "fluids". Lichtenberg figures are named after the German physicist Georg Christoph Lichtenberg, who originally discovered and studied them. Lichtenberg figures are natural phenomena which exhibit fractal properties. Lichtenberg figures are now known to occur on or within solids, liquids, and gases during electrical breakdown. The study of planar Lichtenberg figures along insulating surfaces and 3D electrical trees within insulating materials often provides engineers with valuable insights for improving the long-term reliability of high-voltage equipment. Lichtenberg figures are often associated with the progressive deterioration of high voltage components and equipment. 2003 Jan 13(1):76-9.The slight branching redness traveling up this person's leg was created by current from a nearby lightning strikeĪ Lichtenberg figure (German Lichtenberg-Figuren), or Lichtenberg dust figure, is a branching electric discharge that sometimes appears on the surface or in the interior of insulating materials. Case report of a 13-year-old struck by lightning. IEEE Engineering in Medicine & Biology Magazine. Does a fifth mechanism exist to explain lightning injuries?. Ophthalmic manifestations of lightening strikes. The long-term consequences of lightning injuries. Ocular manifestations of remote lightning strike. Neurologic manifestations of lightning strikes. This is a rare presentation of a forehead lesion which has not been previously described in the literature.ġ. A piece of gravel may have become embedded in the forehead and evoked an inflammatory response in the local tissues. The metal hair-clip may have acted as a conductor for the electricity, and caused the forehead burn which later healed as a supra-orbital scar. It appears the initial lightning strike caused a direct injury to the shoe, causing a hole and dispersing a shower of gravel upwards. The majority of lightning strike victims have associated multi-system involvement, including neurological complications, burns, and associated blunt trauma.įollowing discussion with our astronomy colleagues, the mechanism of injury in our patient has become clearer. Cardiac and respiratory arrest may occur secondary to the direct effects of current. A fifth mechanism, injury by a weak upward streamer that does not become part of a completed lightning channel, has also been discussed in the literature by lightning researchers. The four classical electrical mechanisms of lightning injury are described in engineering journals. The physics of lightning strike and the physiology of lightning injury are discussed widely in the engineering and medical literature. Lightning strike, a natural phenomenon may have potentially disabling sequelae.
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