Today, LED lights are almost ubiquitous in every corner of our lives: street lamps, tunnel lights, mobile phone displays, smart lighting, landscape lights, home lighting… LED has become the absolute protagonist of the lighting industry and is considered the “most important light source revolution in a century”.
However, in reality, the birth of LED was not achieved overnight, but has undergone more than 120 years of scientific exploration, material breakthroughs, and engineering innovation to develop to today.
This article will take you back to the depths of history, from the initial strange phenomena, to the continuous experiments of scientists, to commercial applications and the current era of intelligent lighting, to reorganize the complete development history of LED lights.
1、 Origin: Starting from a faint light spot (1900-1920)
The story of LED does not start with light bulbs, but with “electronics and materials”.
In 1907, British radio engineer Henry Joseph Round accidentally observed a faint yellow green light spot emitted by a silicon carbide (SiC) crystal under the action of current while detecting radio signals. He recorded this phenomenon in Electrical World in the UK.
Although Lande did not continue his in-depth research, this is considered the first discovery of the “Electro Luminescence” (EL) phenomenon by humans, and thus opened the curtain for LED.
The real experimental promoter: Oleg Losev (1920-1940)
In the 1920s, Russian scientist Oleg Losev was the first person to truly attempt systematic research on this luminescent phenomenon. He made the world’s first batch of LED like light-emitting diode structures, also based on silicon carbide.
Lucef even proposed the concept of ‘solid-state semiconductor light-emitting devices can be used in communication equipment’, decades earlier than the laser and modern optoelectronic era.
Unfortunately, due to historical turbulence and lack of attention, his research did not attract the attention of the industrial community and was only collected in scientific literature until it was rediscovered decades later.
2、 Material Revolution: The emergence of truly ‘usable’ LEDs (1950-1960)
Between 1940 and 1960, semiconductor physics developed rapidly, and people gradually understood the decisive role of impurity control in crystal luminescence.
Breakthrough: The emergence of GaAs and GaAsP
The General Electric (GE) team began extensive research on gallium arsenide (GaAs) and gallium arsenide phosphide (GaAsP) in the 1950s and 1960s, which can produce red or infrared light when powered on.
In 1962, American scientist Nick Holonyak Jr. successfully invented the world’s first visible light (red light) LED at GE. He is known as the ‘father of LED’.
Although this LED has low brightness, it marks the official entry of LED into the stage of “engineering and commercialization”.
3、 Commercialization Sprout: From Indicator Lights to Electronic Devices (1970-1980)
After entering the 1970s, LED gradually moved from the laboratory to the market.
But at that time, LED brightness was weak, efficiency was low, and colors were single (red, orange, yellow), so it was mainly used in:
Indicator lights for electronic instruments, indicator lights for electrical switches, calculator digital tubes (7-segment display), simple transportation equipment, electronic clocks. During this period, LEDs could not be used for lighting because their brightness was far from sufficient.
However, due to its extremely long lifespan, low energy consumption, and good shock resistance, LED quickly replaced small light bulb indicator lights and achieved initial success in the industrial field.
4、 Key breakthrough: The birth of blue LED (1990-2000)
If red and yellow LEDs have given the technology industry hope for the future, then the emergence of blue LED has truly propelled LED into the era of lighting.
Why is blue LED so important?
White LED does not directly emit white light, but rather:
Blue LED+phosphor → white light
Therefore, without high brightness blue LED, there would be no white LED.
The legendary breakthrough of three Japanese scientists
In the 1990s, the NICHIA research team in Japan, led by Shuji Nakamura, Isamu Akasaki, and Hiroshi Amano, successfully produced high brightness GaN (gallium nitride) blue LEDs.
This technology is hailed as a ‘world changing invention’, and the three of them were awarded the 2014 Nobel Prize in Physics for it.
The emergence of blue LED represents that LED truly has the conditions to be used as a lighting source.
5、 Popularization of White LED: The Revolution in the Lighting Industry (2000-2010)
With the maturity of blue LED technology, white LED has rapidly entered the commercial market.
During the period of 2000-2010, LED technology made breakthroughs along the way:
The luminous efficiency has increased from tens of lm/W to over 100 lm/W
The service life has been increased from several thousand hours to 30000-50000 hours
Significant cost reduction
The chip architecture is constantly evolving from a horizontal structure to a vertical structure
A large number of lighting factories are shifting from energy-saving lamps to LEDs
Gradually replaced: incandescent lamps, halogen lamps, energy-saving lamps (CFL)
The advantages of LED are gradually being accepted by society:
The energy consumption is 1/8 of that of incandescent lamps
The lifespan is 20-50 times that of traditional light bulbs
Mercury free and environmentally friendly
Small size, easy dimming, low heat
Can be made into various shapes (light strips, panel lights, tube lights, car lights, etc.)
This period is also known as the first year of LED popularization.
6、 LED enters the era of high brightness: comprehensive penetration of intelligence, commerce, and landscape (2010-2020)
LED technology has entered a period of rapid development, with exponential expansion of application scenarios
1) Indoor lighting, LED bulb lights, tube lights, spotlights, track lights, panel lights, multi segment color temperature lights
2) Commercial lighting, supermarket lights, display lights, office lighting fixtures
3) Landscape lighting, building lighting, night tour economy, urban night scene design
4) Road lighting and LED street lights have become mainstream, and urban energy conservation is significant
5) Automotive lighting, LED headlights, laser headlights (LED evolution version)
6) Screen display field, LED display screen (small pitch/micro pitch) Mini LED、Micro LED、 Backlights for mobile phones, televisions, and tablets
LED has transformed from “emitting light” to “comprehensive lighting and display”, becoming the core technology of modern optoelectronic industry.
7、 Future Trends: More Efficient, Intelligent, and Integrated (2020- Future)
The technology industry generally believes that LED is still in a period of rapid technological evolution. The future trends of LED mainly include:
1) Comprehensive popularization of intelligent lighting: Bluetooth/Zigbee/WiFi/Matter, automatic dimming, scene based lighting, human factors lighting (health lighting)
2) Miniaturization and ultra-high brightness: Mini LED for large-scale commercial use, Micro LED entering AR/VR, TV, car
3) Integrated LED+Sensor+Controller: Smart Street Lamp, Smart Lamp Pole+Monitoring+Charging Pile, IoT IoT Lighting System
4) Manufacturing process upgrade: chip efficiency improvement, COB, CSP, DOB multi route development, lower cost, higher light efficiency
5) Environmental Protection and Low Carbon Trends: LED has become the main light source for global energy conservation and carbon reduction, and countries are phasing out incandescent and fluorescent lamps. LED will continue to be the mainstream light source for the next few decades.
Conclusion: A beam of light illuminates century old technology
From the faint glow of Lande in 1907 to the LED urban landscapes, home lighting, and intelligent lighting systems that illuminate the world today
LED has completed a leap from a laboratory wonder to a global mainstream light source in 120 years.
It has not only changed our visual world, but also the energy structure, industrial design, electronic devices, and even the nighttime in cities.
