Lighting events

1879 Edison invented the electric light;
1938 Fluorescent lamp came out;
1959 halogen lamp came out;
1961 High pressure sodium lamp came out;
1962 metal halide lamp;
1969 The first LED light (red);
1976 Green LED lights;
1993 Blue LED lights;
1999 White LED light;
2000 LED is used in indoor lighting.
      Starting in the 21st century, LEDs developed through the wonderful encounter between nature, humans and science will become an innovation in the light world, a green technology light revolution that is essential to mankind. In the 1960s, scientific and technological workers used the principle of semiconductor PN junction light to develop LED light-emitting diodes. The LED developed at that time was made of GaASP, and its light-emitting color was red. This was the first LED light. After continuous development, the LED, which everyone is very familiar with, can emit red, orange, yellow, green, blue and other colors. In 1999, only white LED lights were available.
       Initially, LEDs were used as indicator light sources for instruments and meters. Later, LEDs of various light colors were widely used in traffic signal lights and large-area display screens, resulting in good economic and social benefits. Take a 12-inch red traffic signal light as an example. In the United States, a 140-watt incandescent lamp with long life and low optical efficiency was originally used as the light source, which produces 2000 lumens of white light. After passing through the red filter, the light loss is 90%, leaving only 200 lumens of red light. In the newly designed lamp, 18 red LED light sources are used, which consumes a total of 14 watts including circuit loss, which can produce the same light effect.
      For general lighting, people need white light sources more. In 1998, the white LED was successfully developed. This LED is made by encapsulating GaN chips and Yttrium Aluminum Garnet (YAG) together. The GaN chip emits blue light (λp=465nm, Wd=30nm), and the Ce3+-containing YAG phosphor made by high-temperature sintering is excited by this blue light and emits yellow light with a peak of 550nLED lamp m. The blue LED substrate is installed in a bowl-shaped reflective cavity, covered with a thin layer of resin mixed with YAG, about 200-500nm. Part of the blue light emitted by the LED substrate is absorbed by the phosphor, and the other part of the blue light is mixed with the yellow light emitted by the phosphor to obtain white light.
       For InGaN/YAG white LEDs, by changing the chemical composition of the YAG phosphor and adjusting the thickness of the phosphor layer, white light of various colors with a color temperature of 3500-10000K can be obtained. This method of obtaining white light through blue LEDs has simple structure, low cost, and high technological maturity, so it is most used. The lower the color temperature, the color will be warmer yellow, and as the color temperature increases, it becomes whiter and colder white. All MCWOFI lamps have a color temperature of 5000K, which is the best color temperature for industrial lamps. It gives you the greatest brightness in the dark night, illuminates the farthest corners and the largest space. MCWOFI has its own production plant, if you need to customize the color temperature, you can contact us by email.
     The LED lamp is an electroluminescent semiconductor material chip, which is cured on the bracket with silver glue or white glue, and then connects the chip and the circuit board with a silver wire or gold wire. The surrounding is sealed with epoxy resin to protect the inner core wire. Function, finally install the shell, so the LED lamp has good seismic performance. Here you can refer to our MCWOFI LED work light. The inside is a sealed chip, the waterproof level can reach IP65, and the outside is a stainless steel protective cover, so that it can protect the lamp while ensuring the maximum brightness. Even a transparent lampshade will inevitably reduce the brightness of the lamp.