As the performance of LEDs continues to increase, the application market has also expanded rapidly. The reason behind this is the high-luminance LEDs using GaN and AllnGaP luminescent materials, which have excellent long-life, power-saving, shock-resistant, low-voltage drive. Features, and beyond the light bulbs and halogens, and high luminous efficiency LEDs have been developed in recent years, therefore, the future development of high-brightness LED market will be more rapid and extensive growth.
Among them, the most obvious one is the white LED. In the late 1990s, it was expected by the market in the context of environmental protection and energy conservation. It also stimulated the rapid development of relevant technologies. For the moment, the main applications of white LEDs include mobile phone LCD backlighting and automotive interior lighting. These markets alone account for about 25% of the total LED sales.
On the other hand, the part on lighting applications is in its infancy. The lighting of general buildings often accounts for 20% of the total electricity consumption. In Japan, in the 1990s, it exceeded 100 billion kWh per year. Therefore, the expectations for a new generation of energy-saving light sources are quite large, but unfortunately, white LEDs can only be used in a relatively small range. Because a small white LED like 5mm can't be used like a light bulb or a fluorescent light, the amount of light needed for the environment can be obtained with only one. Therefore, if you want LEDs to be able to cross the building lighting, you need a bigger breakthrough in the overall technology.
High brightness white LED basic structure
There are basically two ways to white LEDs. One is a multi-chip type, and the other is a single chip type. The former is to package the red, green and blue LEDs together, and at the same time, it emits white light, and the latter uses blue or violet or ultraviolet LEDs as the light source to emit white light in combination with the fluorescent powder. In the former way, the characteristics of various LEDs must be combined, and the driving circuit is relatively complicated. In the latter single-chip type, there is only one type of LED, and the circuit design is relatively easy. The single-chip type is further divided into two categories, one is that the light source uses blue LEDs, and the other is using near ultraviolet and ultraviolet light. Nowadays, most of the white LEDs on the market are blue LEDs with YAG phosphors.
In the past, only blue LEDs used GaN as a substrate material, but now LEDs from the green field to near-ultraviolet light have begun to use GaN compounds as materials. And with the expansion of white LED applications, the market's expectations for its efficiency have gradually increased. From a pure point of view, the pursuit of high efficiency has always been expected by the market and the industry. But on the other hand, coloring will also be an important performance indicator. If it is only for display purposes, the color of the illuminating color may be enough, but in terms of lighting, in order to achieve higher efficiency, how to achieve Colors close to natural light are necessary.
In the early days of technology development, only 23 companies in the world developed and produced GaN LEDs. However, the number of producers has reached nearly 10 companies so far, and there has been fierce competition in the market. Compared with the initial stage, although the dramatic brightness increase has been achieved today, the technology is about to face more difficult thresholds, so now both academic and business circles are focusing on technology and research and development. In view of the current research and development direction of GaN LED, it is roughly divided into the development direction of high current, short wavelength, and high efficiency.
How to make LEDs support more current
In recent years, the industry has been very active in developing LEDs that can achieve comparable brightness with only one, so the technology in this area is also how to make LEDs support larger currents. Usually 30um2 LED can drive up to 30mA, but the result is far from meeting market expectations, so the goal is to turn on more than 10 times the current into the LED components. Therefore, when the area size of the LED can be expanded to 1mm2, then the next work is how to make the current value reach 350500mA. Because the driving voltage is more than 3V, 1W of power can be flown into the 1mm2. Chip area.
In terms of illuminating color, although such a large amount of power is input into the GaN LED, three-quarters of the input power cannot be converted into light to form heat, so the LED will overheat, which will directly affect The color rendering result to the LED. Because the basic characteristic of the LED component is that if the temperature rises, the luminous efficiency will decrease and the color rendering property will be deviated. Therefore, how to effectively release a large amount of heat generating technology is the key, so the LED is installed in a large thermal conductivity and a large heat capacity. The material has become a very important issue, and most of the time it is using valuable metals or ceramics.
Short-wavelength brings high energy of excitation light to improve luminous efficiency of fluorescent powder
GaN LEDs starting from Blu-ray have successfully developed high-luminance green LEDs. Although there are also long-wavelength development trends, the crystallinity of InN due to the increase in the crystal-to-crystal ratio has been gradually abandoned. . On the other hand, in order to develop new applications such as laser substitutes, etc., the development of short wavelengths is currently being actively carried out. Recently, some universities in Japan have successfully developed 250nm LEDs, but the practicality remains to be considered, because the human eye accepts wavelengths of about 380nm, so if the wavelength is shorter than 380nm, it is impossible to produce visible. LEDs in the domain may produce low output.
Swivel Disk socket circular design, compact and simple. Power Strip Round 360 ° distribution socket, large spacing, multiple plugs at the same time.
Double break switch + Overload Protection.
Fireproof ABS Plastic, PVC copper cable, Use standard plug. Easy and safe to use for elderly and children.
Qualified Power Cord allowing you extend the outlet 6ft (2 meters) away from the wall or even further.
Extension Cord Round,Swivel Disc Socket,Power Strip Round,Electric Plug Portable Socket
ZhongShan JITONGLONG Plastic Hardware Co. Ltd. , https://www.toukoo-electronics.com