Discussion and Analysis on the Problem of LED Explosion-proof Road Light Attenuation

Discussion and analysis of the problem of LED explosion-proof street light decay The problem of serious luminous decay of LED street lamps needs to be solved from the fundamentals of LED heat dissipation technology. At present, the growth rate of LED street lights in China is higher than that of other countries, and according to statistics, it will still dominate the global market this year**. The gap between the policy and the market, in addition to the LED standards that have not yet been fully regulated for manufacturers to follow, another potential technical problem is the 'severe light decay of LED street lampsThe aforementioned issue of the uniform formulation of LED standards and specifications may already be drafted in the near future. As for the 'severe light decay of LED street lampsDiscussion on the causes of LED street light failure Temperature is actually the key problem of LED street light decay, and LED street lights are stuck in this link. Because the luminous power of LED street lamps is greater than that of household lamps, manufacturers have worked hard on the design of heat dissipation substrate fins and heat dissipation modules. After assembly, they must be painted on the outside of the lamp heat dissipation module to prevent weather erosion. Unexpectedly, the spray paint for external protection sealed the heat of the heat dissipation module back, resulting in poor heat dissipation and led to LED epitaxial light decay. LED epitaxy luminescence heat energy is a small range of concentrated heat energy. In the application of high-power street lamps, the power input power is also large, and the interface temperature of the LED is quite high. When the street lamp continues to work for a long time, if the heat dissipation module cannot effectively dissipate heat, it will It will affect the service life and luminous performance of the LED. The serious light decay of the current LED street lamps is caused by these factors. LED street lights are used outdoors, and there are interference factors of the environment and climate, so most manufacturers use anodized protection on the shell of LED street light radiators, or spray paint to avoid corrosion by acid and alkali substances. The life of anodizing treatment is not long, and it will oxidize and change color after a long time. If the heavy industry is to be removed, it will not only consume time and labor, but also increase maintenance costs; the cost of paint protection is low, and the protection effect is good, but the general paint does not dissipate heat. Function, the lacquer itself will form a barrier effect, which is equivalent to increasing the thermal resistance of the LED street light radiator. Not only does it not help, but because the heat energy is blocked in the radiator, the LED luminous power is reduced, which will cause serious light decay. The above-mentioned serious problems that have always existed in the LED lighting industry are almost the main reasons why the current public works LED street lamps fail to pass the acceptance by the purchasing unit. Recommendations for solving LED street light failure To solve these existing problems, it is recommended that street light manufacturers start with basic materials and solve the problem of high-power LED heat sources from the inside out. For example, when bonding light-emitting components and aluminum substrates, thermally conductive adhesives play a key role. Some manufacturers think that the thermal conductivity of thermally conductive films or thermally conductive pads is better, and the thickness of the film should be as thick as possible, but they did not think about thermal resistance. No matter how good the thermal conductivity is, the thermal resistance of the film thickness is useless. What's more, the thermally conductive adhesive film or soft thermally conductive gasket cannot really adhere to the substrate, and there are actually many pores on the bonding surface. These pores look like hollow air pockets when viewed under an electron microscope, which is another form of thermal resistance. With so many thermal resistances that interfere with heat conduction, the efficiency of heat dissipation and heat conduction is virtually reduced. If the thermal resistance is low, it is necessary to use the thermal conductive adhesive, and the soft ceramic thermal conductive adhesive for screen printing construction is recommended. The soft ceramic thermal conductive adhesive for screen printing construction is different from the traditional laminating thermal conductive adhesive film. The soft ceramic thermal conductive adhesive is soft and semi-liquid. When the screen printer squeegee is applied to the aluminum substrate, the thermal conductive particles will penetrate into the pores on the substrate surface. I fill it to the full. In this way, a completely flat surface with no pores will be formed, and it will be completely adhered to the LED epitaxial substrate. In this way, the thermal resistance is reduced to the lowest level, and the heat can be quickly transferred out, which naturally reduces the ambient temperature of the LED die, prolongs the life of the epitaxy and greatly delays the occurrence of light decay. In addition, due to the ductility of the soft ceramic thermal paint for screen printing construction, it will change with the thermal expansion and contraction of the aluminum substrate during high-temperature baking or reflow. The stress is very small, and it will not cause the aluminum substrate to warp or warp. Will burst. The cost structure of LED lamps is constantly improving with the development of packaging technology, carrier board design, and heat dissipation module structure, and the cost is also decreasing with technological development and market demand. However, not many manufacturers have invested in material improvement. This is mainly related to the history and habits of Taiwan's industrial and commercial development. Taiwanese manufacturers are good at manufacturing process and design, and they pay less attention to material basic research and development. Therefore, when it comes to solving technical problems or reducing costs, it is more inclined to purchase thinking or production management thinking. However, at the time of **, American and Japanese manufacturers will think from the application of materials, reduce costs, improve quality and increase profits from the perspective of **.