How LED lamps are used in small power lighting market

1 light-emitting principle of incandescent lamp: as everyone knows, Edison is an important invention of incandescent lamp, the invention makes people bid farewell to the dark, usher in a bright incandescent lamp. But too much power, it is probably less than 1/10 of the energy has become light, it is the heat to be wasted off. So people are trying to use the new light source to replace the incandescent lamp, energy-saving lamp came into being. Because it compared with cheap and good production, so it has been widely used, has gradually replaced the incandescent lamp trend.

Light emitting principle 2 energy-saving lamp: energy-saving lamp poles are ordinary tungsten. Tungsten heating, can emit electrons. The lamp voltage, both sides with relatively high electric field, the electrons will be accelerated in the tube, the formation of electron flow has certain speed and energy. The lamp is being pumped into the vacuum, which is filled with mercury, known as mercury. In the case of the electric heating of the lamp tube, the mercury evaporated from the liquid state to a gaseous state. The electron flow in at a certain speed on mercury, the mercury atoms are excited into electric ion excited state. Called happened step, the excited state of mercury over a very short period of time to spontaneously fall to the original state, while the release of ultraviolet light, ultraviolet light can not used for lighting. So we in the lamp is coated on the inner wall of some fluorescent substances in the bombardment of ultraviolet light, fluorescent material after being stimulated and can emit more natural light, we can be used for lighting. The more common energy-saving lamps on the market have the general general tube and gradually become the mainstream of the three primary color lamp, and incandescent lamps have the advantages of saving electricity. The difference is that the color of the ordinary light tube is low, and the three primary color of the tube is showing a natural sunlight color, and in the color and light efficiency are more than the general lamp. From the above we can know that Mercury is an intermediary role in the energy-saving lamp, no mercury energy-saving lamps will not shine. Mercury in each tube is very small.

According to the investigation: coarse diameter fluorescent lamp tube diameter of 36 mm of mercury in 25 ~ 45 mg, a tube diameter of 26 mm thin diameter fluorescent lamp mercury content is 20 mg, the compact fluorescent lamp mercury content of a tube diameter of 10 mm was 10 mg. Mercury, which is liquid at room temperature, is a liquid, silvery white liquid metal. The mercury in the fluorescent lamp tube is used as a gas discharge medium, which not only improves the light efficiency of the lamp, but also enriches the types of light sources. Therefore, the current energy-saving light source contains mercury. Because Mercury has a low boiling point and evaporation at room temperature can be discarded after crushing, fluorescent lamp, mercury vapor emitted immediately to the surrounding, allows instantaneous mercury concentration in the air around 10 to 20 milligrams per cubic meter, the state of mercury in the air of the maximum allowable concentration of 0.01 mg per cubic meter. It can also flow with the air. Once the mercury into the human body exceeds a certain threshold, it will destroy the human central nervous system, causing great harm to the body. Mercury enters the human body is difficult to be excluded.

In fact, mercury containing lighting in the use of the process is generally no pollution, pollution is mainly discarded after the electric light source is free to discard, rupture caused by the spread of mercury into the air, endanger human health, pollution of the environment. Because of the difficulty of recycling and the low value of recycling, combined with many other drawbacks, the only way to do so is to eliminate it.

What are the disadvantages of energy-saving lamps

A, the production process and the use of abandoned mercury pollution, the current western countries on mercury pollution is considerable attention

B, as a result of glass products, easy to break, bad transportation, bad installation

C, its power consumption is still too big

D, easy to damage, short life, energy saving is the best portrayal of this sentence

3, LED lamp

LED is made up of class III compounds, such as GaAs (Shen Huajia), GaP (), and GaAsP (P). Therefore, it has the general P-N junction I-N characteristics, namely the forward conduction, reverse cut-off, breakdown characteristics. In addition, under certain conditions, it also has luminescent properties. Under the forward voltage, the electrons are injected into the P region from the N region, and the holes are injected into the N region from the P region. A minority carrier (a few) in the other region is combined with the majority carrier (multiple daughter) to give off light.

That luminescence is occurred in the District of P in, then injected electrons and holes in the valence band direct composite and the light, or the first center of light capture, and hole recombination. In addition to this light composite, some electrons are non luminescent center (the center between the conduction band, lies near the middle) capture, and then recombine with holes each release of energy is not, can not form a visible light. The larger the proportion of the luminescence of the composite with respect to the amount of the non luminescent composite, the higher the efficiency of light quantum. Due to the recombination of light in the small sub diffusion region, the light is only in the vicinity of PN junction within the number of mu m.

Theory and practice show that the band gap Eg semiconductor material and light emitting light wavelength peak area, i.e. lambda = 1240/Eg (mm) in Eg units of electron volts (eV). If you can produce visible light (wavelength of 380nm ~ 780nm red light), the semiconductor material Eg should be between 3.26 ~ 1.63eV. Longer than red light. Now there are infrared, red, yellow, green and blue light-emitting diodes, but the cost of blue light-emitting diodes, high prices,