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Industry news Announce the date:
2005-06-30
Times of view:
7603
History of Capacitor
We know from reports of the lost writings of Thales of Miletus (around 600 BC) that the Ancient Greeks knew how to generate sparks by rubbing balls of amber on spindles. This is the triboelectric effect, the mechanical separation of charge in a dielectric.
The ancient experimenters, however, did not know that the charge density could be dramatically increased by sandwiching the insulator between two metal plates. This was the basis of the capacitor. Ewald Georg von Kleist of Pomerania invented the first recorded capacitor in October 1745. It was a glass jar coated inside and out with metal. The inner coating was connected to a rod that passed through the lid and ended in a metal ball.
Before Kleist's discovery became widely known, a capacitor essentially the same as his was invented independently in January 1746 by the Dutch physicist Pieter van Musschenbroek of the University of Leyden and was named by Abbe Nollet as the Leyden jar.
Benjamin Franklin investigated the Leyden jar, and proved that the charge was stored on the glass, not in the water as others had assumed.
Early capacitors were also known as condensers, a term that is still occasionally used today. It was coined by Volta in 1782 (derived from the Italian condensatore), with reference to the device's ability to store a higher density of electric charge than a normal isolated conductor. Most non-English languages still use a word derived from "condensatore", like the French condensateur or the German kondensator.