The LED lamp is an electroluminescent semiconductor material chip, which is cured with silver or white glue to the bracket, and then connected to the chip and the circuit board by silver wire or gold wire, and sealed with epoxy resin to protect the inner core wire. Function, and finally install the outer casing, so the LED lamp has good seismic performance.
LED (Light Emitting Diode), a solid-state semiconductor device that converts electrical energy into visible light, can directly convert electricity into light. The heart of the LED is a semiconductor wafer. One end of the wafer is attached to a holder, one end is the negative pole, and the other end is connected to the positive pole of the power supply, so that the entire wafer is encapsulated by epoxy resin.
The semiconductor wafer consists of two parts, one part is a P-type semiconductor, in which the hole dominates, and the other end is an N-type semiconductor, which is mainly electrons here. But when the two semiconductors are connected, they form a P-N junction. When a current is applied to the wafer through the wire, the electrons are pushed toward the P region. In the P region, electrons recombine with the holes, and then the energy is emitted in the form of photons. This is the principle of LED light emission. The wavelength of light, which is the color of light, is determined by the material that forms the P-N junction.
The LED can directly emit red, yellow, blue, green, cyan, orange, purple, and white light.
For general lighting, people need a white light source. In 1998, white LEDs were successfully developed. This LED is made by encapsulating a GaN chip and yttrium aluminum garnet (YAG). The GaN chip emits blue light (λp=465nm, Wd=30nm), and the Ce3+-containing YAG phosphor prepared by high-temperature sintering is excited by the blue light to emit yellow light, and the peak value is 550n LED lamp m. The blue LED substrate is mounted in a bowl-shaped reflective cavity covered with a thin layer of resin mixed with YAG, about 200-500 nm. The blue portion of the LED substrate is absorbed by the phosphor, and the other portion of the blue light is mixed with the yellow light emitted by the phosphor to obtain white light.