Kirlian photography refers to a form of contact print photography, theoretically associated with high-voltage. It is named after Semyon Kirlian, who in 1939 accidentally discovered that if an object on a photographic plate is connected to a source of high voltage, small corona discharges (created by the strong electric field at the edges of the object) create an image on the plate.

Kirlian's work, from 1939 onward, involved an independent rediscovery of a phenomenon and technique variously called "electrography," "electrophotography," and "corona discharge photography." The underlying physics (which makes xerographic copying possible) was explored as early as 1777 by Georg Christoph Lichtenberg (see Lichtenberg figures). Later workers in the field included Nikola Tesla; various other individuals explored the effect in the later 19th and early 20th centuries. Yet Kirlian took the development of the effect further than any of his predecessors.

In controversial metaphysical contexts, Kirlian photography, Kirlian energy, and so on, are sometimes referred to as just "Kirlian." Kirlian made controversial claims that his method showed proof of supernatural auras, said to resemble a rough outline of the object like a colorful halo. One of the more striking aspects of Kirlian photography is its reputed ability to illuminate the acupuncture points of the human body[citation needed]. An experiment advanced as evidence of energy fields generated by living entities involves taking Kirlian contact photographs of a picked leaf at set periods, its gradual withering being said to correspond with a decline in the strength of the aura. Scientifically, it is considered more likely that as the leaf loses moisture it becomes less electrically conductive, causing a gradual weakening of the electrical field at the drier edges of the leaf.

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