Holonyak, Jr. (born in Zeigler, Illinois on November 3, 1928) invented
the first visible LED in 1962 while working as a consulting scientist
at a General Electric Company laboratory in Syracuse, New York and
has been called "the father of the light-emitting diode".
1960’s Red indicator LEDs
The first commercial LEDs were commonly used as replacements for
incandescent indicators, and in seven-segment displays, first in
expensive equipment such as laboratory and electronics test equipment,
then later in such appliances as TVs, radios, telephones, calculators,
and even watches (see list of signal applications). These red LEDs
were bright enough only for use as indicators, as the light output
was not enough to illuminate an area.
1970’s 7-segment displays
Seven-segment LED displays were in widespread use in the 1970s and
1980s, but increasing use of liquid crystal displays, with their
lower power consumption and greater display flexibility, has reduced
the popularity of numeric and alphanumeric LED displays.
1980’s Green LEDs
Additional colors were manufactured out of similar alloys and by
the Mid 70's Red, Green and yellow LEDs could be found in calculators,
digital watches etc. Defects in crystal structure and poor substrate
creation meant that light outputs were still not great.
1990’s “High brightness” blue (Nakamura, Nichia)
The first high-brightness blue LED was demonstrated by Shuji Nakamura
of Nichia Corporation. Nakamura graduated from the University of
Tokushima in 1977 with a degree in electronic engineering, and obtained
a master's degree in the same subject two years later, after which
he joined the Nichia Corporation, also based in Tokushima. It was
while working for Nichia that Nakamura invented the first high brightness
GaN LED whose brilliant blue light, when partially converted to yellow
by a phosphor coating, is the key to white LED lighting, and which
went into production in 1993.
2000’s Illumination LEDs
The invention and development of the high power white light LED led to use for illumination.