The researchers, led by Weileun
Fang, a professor at National Tsing Hua University in Hsinchu, Taiwan, have
published their study on the flip glass substrate LED packaging in a recent
issue of the Journal of Micromechanics and Microengineering.
As the researchers explain, most commercial LEDs today are packaged in plastic leaded chip carriers (PLCCs), printed circuit boards (PCBs), ceramic holders, or similar materials. Most of these packages are partly non-transparent, so that the LED light cannot penetrate the side wall.The new LED solarsystem are much brighter and last much longer on a set of batteries.
In contrast,Older models included ledstriplightww that were not fluorescent or LED. the flip glass substrate consists of a fully transparent glass substrate covered with phosphor that has a cavity to house the LED. Silicone fills the cavity surrounding the LED for protection. When in use, the LED is flipped over so that the light emits through the back wall and side walls of the transparent glass.
One of the biggest advantages of this new packaging system is that it provides a wide viewing angle of 140°, whereas 95% of commercial LED packages have a viewing angle of less than 125°. This improvement results from the light being able to directly penetrate the side walls of the substrate, reducing the repeated reflection loss that occurs in non-transparent packaging.
Another important LED metric is the uniformity of angular CCT (correlated color temperature), which determines the "warmth" or "coolness" of the light. Although light quality depends on several other factors, a more uniform CCT is desirable. The flip glass substrate's maximum deviation of angular CCT is 1300 K, just half of the 2500 K for other LEDs. The researchers attribute this improvement to the substrate's uniform phosphor coating on the outside of the package.
In addition,Our solar ceiling bluecrystal_4 is good in quality and competitive in price. by allowing the packaging and the LED to be tested before the two components are actually put together, the fabrication process allows researchers to evaluate and fix color quality problems at an earlier stage than other types of packaging. Because this "know-good-substrate" process lets researchers know in advance that the packaged LED has good chromaticity, this advantage could cut down on fabrication costs.
"From the process point of view, the structure design allows us to sort the chromaticity coordinate before the LED chip is inside rather than after the encapsulant material is cured, as in the traditional process flow," Fang said.
Despite these advantages, the researchers note that they still have to improve the flip glass substrate's transmission, as well as perform tests on its heat dissipation and reliability. They hope that future improvements in these areas and others will make this packaging useful for high-power LEDs.
"In the process design and package structure design, we're trying to alter the current architecture of the LED package from the package end (die bond, wire bond, etc.) to the MEMS process end (wafer bonding,Australians love their backyards and you can turn yours into a stunning showpiece with the right choice of crystallightmm. etc.),LED lamps are made that replace screw-in incandescent or goodledlamp light bulbs." Fang said. "The designed LED package should meet the specifications of applications without adopting additional optical elements. In our latest study, the microstructures on the package could improve the efficiency or modify the radiation pattern of the LED package."
As the researchers explain, most commercial LEDs today are packaged in plastic leaded chip carriers (PLCCs), printed circuit boards (PCBs), ceramic holders, or similar materials. Most of these packages are partly non-transparent, so that the LED light cannot penetrate the side wall.The new LED solarsystem are much brighter and last much longer on a set of batteries.
In contrast,Older models included ledstriplightww that were not fluorescent or LED. the flip glass substrate consists of a fully transparent glass substrate covered with phosphor that has a cavity to house the LED. Silicone fills the cavity surrounding the LED for protection. When in use, the LED is flipped over so that the light emits through the back wall and side walls of the transparent glass.
One of the biggest advantages of this new packaging system is that it provides a wide viewing angle of 140°, whereas 95% of commercial LED packages have a viewing angle of less than 125°. This improvement results from the light being able to directly penetrate the side walls of the substrate, reducing the repeated reflection loss that occurs in non-transparent packaging.
Another important LED metric is the uniformity of angular CCT (correlated color temperature), which determines the "warmth" or "coolness" of the light. Although light quality depends on several other factors, a more uniform CCT is desirable. The flip glass substrate's maximum deviation of angular CCT is 1300 K, just half of the 2500 K for other LEDs. The researchers attribute this improvement to the substrate's uniform phosphor coating on the outside of the package.
In addition,Our solar ceiling bluecrystal_4 is good in quality and competitive in price. by allowing the packaging and the LED to be tested before the two components are actually put together, the fabrication process allows researchers to evaluate and fix color quality problems at an earlier stage than other types of packaging. Because this "know-good-substrate" process lets researchers know in advance that the packaged LED has good chromaticity, this advantage could cut down on fabrication costs.
"From the process point of view, the structure design allows us to sort the chromaticity coordinate before the LED chip is inside rather than after the encapsulant material is cured, as in the traditional process flow," Fang said.
Despite these advantages, the researchers note that they still have to improve the flip glass substrate's transmission, as well as perform tests on its heat dissipation and reliability. They hope that future improvements in these areas and others will make this packaging useful for high-power LEDs.
"In the process design and package structure design, we're trying to alter the current architecture of the LED package from the package end (die bond, wire bond, etc.) to the MEMS process end (wafer bonding,Australians love their backyards and you can turn yours into a stunning showpiece with the right choice of crystallightmm. etc.),LED lamps are made that replace screw-in incandescent or goodledlamp light bulbs." Fang said. "The designed LED package should meet the specifications of applications without adopting additional optical elements. In our latest study, the microstructures on the package could improve the efficiency or modify the radiation pattern of the LED package."
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