A History Of Light-emitting Diode
LED is an electric component which works on electroluminescent principle and when connected to direct current emits lights as well as UV and infrared. They have a specification of a longer lifespan, low energy consumption, different size and colour as per need of the consumer. Due to the advantages, they are used in a wide range from indoor to outdoor.
At the beginning of the twentieth century, LED effect was first recorded. A British experimenter named H J Round was working for Marconi undertook some experiments using carborundum (silicon carbide) crystal which emits yellowish light. For many years the idea of LED remained dormant. However, It was observed again with working theory by Russian engineer Oleg Vladimirovich Losev. In 1927, Losav published an article on paper regarding “Luminous carborundum detector and detection effect and oscillations with crystals“. For a long period of time, no progress was made due to many reasons.
Then In 1961, Robert Biard and Gary Pittman in Texas Instruments invented an infra-red LED. However, this light was invisible to human beings and also they received a patent for infrared LED. In 1962, Nick Holonyak Jr, Working with General Electric invented the first LED which produces visible red light. For this, he is known as “Father of LED”. Then a red LED was made using Gallium Arsenide Phosphide on a Gallium Arsenide substrate. Soon afterwards, Orange LED was invented and produced. M. George Craford employed of the Monsanto Company, In 1972, invented yellow LED and also brighter red LED than Holonyak’s version
In 1976, Thomas P. Pearsall developed high brightness LED using fibre optics. During mid-1970, scientists started experimenting for green light LED. By the end of the decade, they gave the improved version of a green LED. In mid-1970, Fairchild Optoelectronics began to produce low-cost LED devices which increase the use of LED Light.
LEDs are used replacement for traditional like incandescent and fluorescent light. Nowadays LED Lights have used on large scale in commercial, industrial, residential etc., to invoke more cost saving.