The Elusive Blue LED: How Did Researchers Finally Triumph? (Download)
It’s hard to believe that the first blue LED didn’t arrive until 1993. They look simple, but looks are deceiving.
James R. Biard and Gary E. Pittman, Texas Instruments engineers, accidentally created the first LED in 1961. At the time, they collaborated on a project, developing low-noise parametric amplifiers for X-band radar receivers, and found a diode they created on a gallium-arsenide substrate that emitted infrared light. In 1962, the SNX-100 GaAs LED, the first commercial LED, was released. That same year, GE physicist Nick Holonyak created the first red LED.
Producing various LED colors involved applying electric currents to materials with distinct molecular structures. Researchers observed how the energy bandgap of each material influenced wavelength, and therefore, the color of the emitted light.