History of LED

1907 – Electroluminescence discovered by Henry joseph Round. He observed this by applying an electrical current to silicon carbide, which emitted a yellowish light.

1927 – First noted creation of LED reported by Russian inventor Oleg Losev. However, no real progress in the field of electroluminescence or LEDs was made in the following decades.

1961 – Gary Pittman and Bob Biard from Texas Instruments, invented an infrared LED. Nonetheless the light was invisible to the human eye, so no commercial use was found.

1962 – First LED that could produce a visible red light invented by Nick Holonyak Jr.

1972– First yellow LED and brighter red LED than from Holonyak was invented by M. George Craford, a student of Holonyak.

Mid 1970s – Scientists started using only Gallium Phosphide to make LEDs that emitted a pale green light. Fairchild Semiconductor also succeeded in that time to reduce the cost of single LED to 5 cents by using planar process of semiconductor chips for LEDs. This led to LED being used as a commercial product, very popular in electronics.

1979 – Blue LED invented by Shuji Nakamura.

1980s – Further research and development of LED technology led the invention of super-bright red, yellow and green LEDs

1990s – Ultra-bright orange-red, orange, green and yellow LEDs were developed by experimenting with Indium Gallium Aluminum Phosphide as the semiconductor material.

1994 – Shuji Nakamura discovered the ultra-bright blue LEDs using Gallium Nitride and high-intensity blue and green LEDs while using Indium Gallium Nitride. The big discovery that has been made was by coating the blue light-emitting chip with fluorescent phosphors, the diode would emit a bright white light. The ultra-bright blue LEDs were the foundation for the development of the cost-efficient and highly functional white LEDs which today are commonly used in manufacturing and commercial spaces.