The Complete History of LED: From Electroluminescence to the Modern Lighting Revolution

History of LEDs Documenting humanity's long journey in understanding and controlling light through semiconductor technology. From the experiments of early-20th-century scientists to ultra-efficient lighting in homes and on the streets today, the story of LEDs has become one of the key milestones in the history of electronic technology.

The basic phenomenon that gives rise to LEDs is electroluminescence, namely the ability of a solid material to emit light when an electric current is passed through it. From this simple scientific discovery, the world of science opens a new chapter in light engineering.

The Beginning of Discovery: Electroluminescence and Early Experiments

The phenomenon of electroluminescence was first observed more than a century ago. At that time, scientists had not fully understood how an electric current could trigger the emission of light from certain materials.

Henry Round and the Discovery of Light from Silicon Carbide

In 1907, an English scientist Henry Joseph Round reporting shocking observations. They found that silicon carbide (SiC) It can emit a faint light when electricity is supplied. This discovery becomes the starting point of scientific documentation concerning the phenomenon of electroluminescence.

Round did not develop electronic devices based on his findings, but his experiments became the theoretical foundation for the next generation of researchers. The phenomenon shows that light can be produced not only through heat, as in incandescent lamps, but from the process of electrons in solid materials.

Oleg Losev and the First LED in the laboratory

A few years later, between 1921 to 1927, Russian physicist Oleg Vladimirovich Losev go further. He succeeded in creating. the diode that emits light The forerunner of modern LEDs. Losev published a series of scientific papers that explain how a particular semiconductor junction can produce light emission when current flows.

However, Losev's device had not yet been efficient and could not be mass-produced due to material and technological limitations of its time. Nevertheless, this research became the foundation for the development of LEDs several decades later.

The emergence of infrared and red LEDs.

Significant development History of LEDs It occurred in the mid-20th century when scientists began producing light-emitting diodes that could be used practically.

Invention of the Infrared LED

Around the year 1961, two scientists from Texas Instruments James R. Biard dan Gary Pittman Registering a patent for an emitting semiconductor diode. infrared lightThis discovery marks a real step toward commercially producible LEDs, although not visible to the human eye.

Not long after, infrared LEDs began to be used in remote control devices and optical communication systems.

Nick Holonyak Jr. and the First Red LED

on 1962, Nick Holonyak Jr., scientists who worked at General Electric, created the first red LED that is visible to the naked eye. This is an important moment in the history of digital lighting.

Red LEDs are to be used immediately in electronic devices such as power indicator, calculator, and digital clock, replacing the energy-inefficient mini incandescent bulbs. However, the color produced is still limited to the red spectrum, and its light intensity is not very bright yet.

Color Expansion and Major Innovations in the 1970s–1980s

After the red and infrared LEDs were successful, scientists raced to create a new color. The focus of research has shifted to new semiconductor material such as gallium phosphide (GaP) and gallium arsenide phosphide (GaAsP).

George Craford and the First Yellow LED

In the year 1972, George Craford, a former Holonyak student, develops yellow LED as well as increasing the brightness of the red LED up to tenfold from the previous generation. This innovation expands LED applications to more complex display devices.

the increasingly wide color spectrum

During the 1970s and 1980s, green, orange, and yellow LEDs were developed. This color variation enables creation. multicolor display, which forms the basis for modern digital displays such as electronic signs, LED clocks, and calculator screens.

Blue LED Challenge

However, the world of science faces heavy challenges: There is no bright blue LED yet. which is efficient. Without the blue color, it is not possible to create white light or a full RGB combination.

Blue LED Breakthrough and the Birth of White LEDs

The 1990s marked a new phase. History of LEDs When Japanese scientists managed to solve the mystery of the blue LED.

Shuji Nakamura, Isamu Akasaki, and Hiroshi Amano

Three Japanese scientists, Shuji Nakamura, Isamu Akasaki, dan Hiroshi Amano successfully created bright blue LED-based gallium nitride (GaN) dan indium gallium nitride (InGaN)This innovation is the key to producing white light by adding phosphor or by combining red, green, and blue LEDs.

Their success opened a major revolution in the world of lighting and digital displays. on the year 2014, all three were awarded Nobel Prize in Physics Regarding this discovery.

White LED Revolution

With the advent of blue LEDs, there was created. white LED lamp that is efficient and durable. Starting in the late 1990s, white LED technology began replacing incandescent and neon lamps in various fields, from home lighting to traffic lights and automotive.

Commercialization and Broad Adoption

Technological advances have brought LEDs from the laboratory to the global market.

First Commercial LED Product

In fact, the first LED was sold commercially by Texas Instruments on 1962 with a model SNX-100, even though it only emits infrared light. However, the 2000s became the peak of LED dominance in the global lighting industry.

The dominance of LEDs in the 21st century.

LED is now present in almost every aspect of life:

• House lights and street lights Save energy.

• TV screens, smartphones, and digital billboards.

• Electric vehicles and airplanes.

• Medical devices, communications, and industrial sensors.

With efficiency up to 90% more economical compared with incandescent lamps and service life up to 50,000 hours, LED has become a symbol of sustainable innovation.

The Future and Trends in LED Technology

After more than a century of evolution, LEDs continue to move toward a more advanced future.

The era of Micro-LEDs and Nano-LEDs.

One of the major trends is micro-LED, where the size of each diode is less than 100 micrometers. This technology enables a screen with high resolution, extreme brightness, and very low power consumption.

Large companies like Apple and Samsung are now racing to develop. micro-LED display for future devices, including smartwatches, premium TVs, and augmented reality headsets.

Materials Innovation and Energy Efficiency

The researchers also develop. new material such as perovskite and quantum dots to improve efficiency as well as broaden the color spectrum. This effort makes LED not only a lighting tool, but also a center of innovation in photonics and optical communications.

Impact on the Environment and Energy Policy

LED plays a major role in green energy transitionMany countries now require the use of LED lamps in energy efficiency regulations to reduce global carbon emissions.

The history of LEDs shows how small scientific research can change the face of the world. From the weak light of silicon carbide to the high-resolution micro-LED revolution, this long journey is proof that technological innovation can be born from the perseverance of scientists across generations.