The History of LEDs
The history of LEDs offer a fascinating journey. LEDs are light-emitting diodes that when connected to electricity emits a light. Also, they have characteristically low energy consumption, small size, and longer lifetime. The history of LEDs begins in 1907, British experimenter Henry Joseph Round noticed for the first time that when 10volts are applied to carborundum (silicon carbide) crystal, it emits yellowish light. Oleg Vladimirovich Losev from Russia came to the same conclusion and in 1927, he published text about first light-emitting diode.
In 1961, Gary Pittman and Bob Biard from Texas Instruments found that that gallium-arsenide diode emits infrared light every time it is connected to current. The same year they received a patent for the infrared LED the color red. In 1972, M. George Craford invented the first yellow LED and a brighter red LED. In 1976, Thomas P. Pearsall developed high brightness light-emitting diode. Finally, in 1979, Shuji Nakamura of Nichia Corporation made the first blue LED. But it was too expensive for commercial use until 1994.
LEDs Don’t have:
- Fragile filaments to break or burn out
- Glass to shatter
- Energy consuming ballasts or starters
- Burnout failures
- Toxic substances like Mercury
- Harmful Ultraviolet light
- Stroboscopic effect or flickering
- Environmentally friendly
- Fully recyclable
- Clean, safe technology
- Very long life time
- Extremely low energy consumption
- Cheapest operating and maintenance cost
- Lowers air conditioning costs by generating less heat
Furthermore, since 1994, LEDs have been used almost everywhere. Since they are suitable for any location and are environmentally friendly.