[Source: "High - tech LED - Technology and Applications" December issue ]
Foreword
At present, the mainstream of high power on the market is packaged with imitation lumens. This has been done for a long time, and it is widely used in various types of lamps. Similar packages have achieved good results in terms of light efficiency and heat dissipation, but the volume is good. Large and high cost are the shortcomings of this kind of package. Therefore, in recent years, 3535 and 5050 ceramic packages represented by Cree-XP have appeared. The light effect is comparable to the imitation lumen package, and the volume is small, but the disadvantage is that the unit price is high and manufacturing is difficult. It can only be used in some high-end applications and cannot be popularized by the general public. In this paper, we try to use the 5050 bracket for high-power packaging, and use automatic molding to make the lens to achieve the imitation lumens and Cree-XP packaging effect in terms of cost, light efficiency and heat dissipation.
Foreword
At present, the mainstream of high power on the market is packaged with imitation lumens. This has been done for a long time, and it is widely used in various types of lamps. Similar packages have achieved good results in terms of light efficiency and heat dissipation, but the volume is good. Large and high cost are the shortcomings of this kind of package. Therefore, in recent years, 3535 and 5050 ceramic packages represented by Cree-XP have appeared. The light effect is comparable to the imitation lumen package, and the volume is small, but the disadvantage is that the unit price is high and manufacturing is difficult. It can only be used in some high-end applications and cannot be popularized by the general public. In this paper, we try to use the 5050 bracket for high-power packaging, and use automatic molding to make the lens to achieve the imitation lumens and Cree-XP packaging effect in terms of cost, light efficiency and heat dissipation.
1.5050 high power introduction
At present, the problems faced by LED lamp beads are mainly how to improve the light efficiency, reduce the cost and achieve good heat dissipation, in order to maintain a long life. From the above thinking, we use a low-cost bracket, a large heat dissipation area, and a lens at a time. Improve light extraction efficiency. The current sample of lamp bead and bulb lamp are as shown below. The lens part is made of silica gel, which has good thermal stability. It is different from the current PC lens for imitation lumen packaging and cannot be reflowed. The 5050 high-power package can be mass-produced using a placement machine, and it is small in size and easy to design for use on lamps.
At present, the problems faced by LED lamp beads are mainly how to improve the light efficiency, reduce the cost and achieve good heat dissipation, in order to maintain a long life. From the above thinking, we use a low-cost bracket, a large heat dissipation area, and a lens at a time. Improve light extraction efficiency. The current sample of lamp bead and bulb lamp are as shown below. The lens part is made of silica gel, which has good thermal stability. It is different from the current PC lens for imitation lumen packaging and cannot be reflowed. The 5050 high-power package can be mass-produced using a placement machine, and it is small in size and easy to design for use on lamps.
2. Luminous efficiency
In terms of light extraction efficiency, we used a special reflector cup and a thin 0.8 mm bracket to optimize the light extraction effect, and used a molding lens to increase the luminous flux and illumination angle. Figure 5 is a simulation effect diagram made by tracepro to understand the effect of the silicone lens on the light extraction efficiency of the LED. The simulation results show that the light extraction effect of the addition lens is 10% higher than that of the unattached lens, and the angle of the light extraction can be Increasing 20 degrees, it is very suitable for bulbs and other lamps that require large-angle illumination. The actual measurement of the luminous flux can be increased by about 5~10%, which is close to the actual simulation. And in later applications, we can change the lens once to achieve different light-emitting effects. For example, in applications that require a small angle, such as flashlight or streetlight applications, the lens can be changed to match different application ranges.
In terms of light extraction efficiency, we used a special reflector cup and a thin 0.8 mm bracket to optimize the light extraction effect, and used a molding lens to increase the luminous flux and illumination angle. Figure 5 is a simulation effect diagram made by tracepro to understand the effect of the silicone lens on the light extraction efficiency of the LED. The simulation results show that the light extraction effect of the addition lens is 10% higher than that of the unattached lens, and the angle of the light extraction can be Increasing 20 degrees, it is very suitable for bulbs and other lamps that require large-angle illumination. The actual measurement of the luminous flux can be increased by about 5~10%, which is close to the actual simulation. And in later applications, we can change the lens once to achieve different light-emitting effects. For example, in applications that require a small angle, such as flashlight or streetlight applications, the lens can be changed to match different application ranges.
3. Thermal evaluation
The most important factor affecting the performance of LED lamps is the design of heat dissipation. For the heat dissipation design, the 5050 bracket adopts a 0.2 mm copper ultra-thin heat dissipation design to increase the heat dissipation area to increase the heat dissipation effect. In a 7W bulb, try to measure the solder joint temperature at about 25 ° C at room temperature of 25 ° C, and 113 ° C in an oven at 90 ° C. The result of the current test is that if there is a good heat dissipation path at 1W power, the heat dissipation condition is good and the thermal resistance is quite low, which also ensures the durability of the 5050 lamp bead. Long-term light decay test is currently underway. There is no obvious light decay for two months, and will continue to be observed later.
Unfinished
For more information, please refer to "High - tech LED - Technology and Applications" December issue
The most important factor affecting the performance of LED lamps is the design of heat dissipation. For the heat dissipation design, the 5050 bracket adopts a 0.2 mm copper ultra-thin heat dissipation design to increase the heat dissipation area to increase the heat dissipation effect. In a 7W bulb, try to measure the solder joint temperature at about 25 ° C at room temperature of 25 ° C, and 113 ° C in an oven at 90 ° C. The result of the current test is that if there is a good heat dissipation path at 1W power, the heat dissipation condition is good and the thermal resistance is quite low, which also ensures the durability of the 5050 lamp bead. Long-term light decay test is currently underway. There is no obvious light decay for two months, and will continue to be observed later.
Unfinished
For more information, please refer to "High - tech LED - Technology and Applications" December issue
Shenzhen Hongyian Electronics Co., Ltd. , https://www.hongyiancon.com