ABSTRACT
It has been known for centuries that many compounds emit visible radiation when they are exposed to sunlight. Luminescence phenomena, such as the aurora bore alis, phosphorescence of the sea, luminous animals and insects, phosphorescent wood, etc., have fascinated man since antiquity, being reflected in the early scien tific literature. Aristotle (384-322 b.c.) appears to be one of the first philosophers to recognize “ cold light” in dead fish, fungi, and the luminous secretion of the cuttlefish [1].