The development of LED is the second revolution after the development history of incandescent lamp lighting for more than 120 years.
In the 1960s, researchers in science and technology developed LED light-emitting diodes by using the principle of the semiconductor p-n junction. At that time, the material of LED was GaASP, and the color was red. After nearly 30 years of development, people are very familiar with LED, which has been able to emit red, yellow, blue, green and other colors of light. But the white light that is often used in lighting did not develop until 2000.
The development of
The earliest LED light source made of semiconductor p-n junction luminescence principle appeared in the early 1960s. The material used at the time was GaAsP, or red light (lambda =650nm), with a luminous flux of only a few thousandths of a lumen when the driving current is at 20 milliamps. The corresponding luminous efficiency is about 0.1 lumens per watt.
By the mid-1970s, the original elements In and N were introduced, so that the LED produced green light (lambda =555nm), yellow light (lambda =590nm) and orange light (lambda =610nm), and the luminous efficiency reached 1 lumen per watt.
In the early 1980s, GaAlAs's LED light was introduced, which allowed red light to reach up to 10 lumens per watt.
LED optical efficiency was greatly improved in the early 1990s with the development of GaAlInP, which emits red and yellow light, and GaInN, which produces green and blue light.
In 2000, the former was at 100 lumens per watt for the red or orange zone, while the latter was at 50 lumens per watt for the green zone.
With the continuous development of society, from the beginning of the 21st century, the LED developed by nature, human beings and science will be a major innovation in the light world and an indispensable contribution to human beings. LED will be another great light revolution since Edison invented the light bulb.
At present, LED street lamp, LED projection lamp, LED fluorescent lamp, LED floodlight can be mass-produced. For example, a 10-watt LED fluorescent lamp can be replaced with a 40-watt ordinary fluorescent lamp or energy-saving lamp.
LED energy-saving lamp has gradually entered the home of ordinary people, which means that LED energy-saving lamp is more and more popular!