Determination of Chromaticity Coordinates and Bandgaps of III-V LEDs Using Electroluminescence Spectroscopy

In 1907 English engineer Henry Joseph Round was testing the rectifying current behaviour of SiC crystallites and noticed that a faint yellow light was emitted from the SiC; this was simultaneously the first reported observation of the phenomena of electroluminescence spectroscopy and the first successful operation of a light emitting diode (LED). The work of Round was expanded on by a few others in the early 20th century, but it would take many decades for LEDs to become efficient enough for practical use. In the 1960s the first commercial LEDs were released which had emission in the NIR and red regions of the spectrum. It would take another 30 years for the breakthrough of high efficiency InGaN based blue and green LEDs, in the late 1990s, to usher in the age of the LED.

In 1907 English engineer Henry Joseph Round was testing the rectifying current behaviour of SiC crystallites and noticed that a faint yellow light was emitted from the SiC; this was simultaneously the first reported observation of the phenomena of electroluminescence spectroscopy and the first successful operation of a light emitting diode (LED). The work of Round was expanded on by a few others in the early 20th century, but it would take many decades for LEDs to become efficient enough for practical use. In the 1960s the first commercial LEDs were released which had emission in the NIR and red regions of the spectrum. It would take another 30 years for the breakthrough of high efficiency InGaN based blue and green LEDs, in the late 1990s, to usher in the age of the LED.