As shown in Figure 2-25, in order to improve external quantum efficiency (hereinafter known as the light extraction efficiency), in addition to the metal reflective layer, the electrode structure also made modest improvements. Reflector with a light-emitting layer can generate the direction of reflected light toward the substrate, so that light from the LED surface removed. Reflective layer is located at the four-dimensional LED between the film and LED datasheet and the Au layer, made of Al. Quality adoption Al reflective layer is intended to fit the LED to avoid heat impact on the reflectivity, although Au reflective layer material has a better reflectivity, but the temperature in the fitting process in addition to make the four-dimensional LED and LED price and Au film deterioration of the interface between layers, it...

LED packaging technology, mostly in discrete packaging technology based on the development and LED datasheet and evolved, but it is very special nature. In general, discrete devices are sealed in the package the die body, the main role of packaging is to protect the die and LED price and electrical connections completed. The LED package is to complete the output signal, to protect the die work, the output function of visible light, both electrical parameters of the design and LED suppliers and technical requirements, but also optical parameters of the design and technical requirements, it is not simply the discrete devices packaging technology for LED packages. LED light-emitting part of the core by the P-and N-type semiconductor PN junction consisting of the die, when injected into the PN junction of the minority carrier and majority ...

Luxeon high power LED in the thermal performance significantly better than the ordinary low-power LED, the LED chip which is connected to a metal embedded chip, cooling performance is greatly improved. However, for special high-power LED lamps, or lamps for use in harsh environments, these lamps are generally in the enclosure rating IP65 above, if the shell is non-metallic (eg plastic) material, although the LED connected to the aluminum plate ( MCPCB), but the aluminum plate can not be effective if the heat conduction to the surface of the shell, then gather the heat will rapidly increase the temperature of the aluminum plate, causing the temperature is too high, increasing the likelihood of failure of the LED, the LED light failure caused by increased , shortened life expectancy. theor...

LED has been widely used in lighting, decorative lighting products, LED lighting systems in the design, the need to consider the choice of what kind of LED drivers and LED datasheet and LED as the load used in series and LED price and parallel, with reasonable design, to ensure the LED to work properly. LED driver circuit as the load, often dozens or even hundreds of LED components together constitute a light, LED load connection form is directly related to its reliability and LED suppliers and service life. Select the LED driver circuit design, generally consider the cost and performance factors. System design of a constraint is battery power and voltage available, other constraints include features, such as to adjust for ambient light. LED screening according to different parameters, including the forward voltage and forward current o...

There are various forms of raw power, but no matter what kind of power, are generally not directly to the LED. Therefore, to use LED lighting will do to solve power conversion problems. High-power LED is actually a current-driven low-voltage unidirectional conductive devices, LED drivers should have a DC control, high efficiency, PWM dimming, over-voltage protection, load disconnect, small size and LED datasheet and ease of use and LED price and other characteristics. LED power supply to the converter must be designed to note the following: LED is unidirectional conductive devices, due to this feature, it is necessary to use DC current or pulse current to the LED-powered one-way. LED is a PN junction structure of semiconductors, with a potential barrier, which formed a turn-on threshold voltage, plus the LEDs volt...

LED lighting to replace the current widespread use of incandescent, fluorescent, gas discharge lamp, there are some technical problems to be studied and LED datasheet and solved. luminous efficiency. Improve the efficiency of the LED light is the most important semiconductor light-emitting materials to improve the structure and LED price and the LED chip manufacturing process. As this part of the work requires a solid theoretical basis for research and LED suppliers and advanced semiconductor process equipment, the need to carry out research work in this area to increase the human and material resources. high-power issues. For lighting, a single LED chip output luminous flux must be large enough, and wish to increase the LEDs luminous flux, we must first injection of sufficient electric power. But the LED chip temperature rise is no...

LEDs emitting surface is small, narrow beam, high brightness characteristics determine its specificity testing, in order to deal with this problem, CIE has established a "TC2-45 LED Measurement" and LED datasheet and "TC2-46 CIE / ISO LED intensity measure of the" two technical committees. CIE TC2-34 team in the October 1997 meeting held at the headquarters in Vienna, developed and LED price and recommended CIE127-1997 LED measurement standards, which involves LED radiometric, photometric and LED suppliers and colorimetric measurement. However, due to the rapid development of LED technology in recent years, especially in white LED lighting products, many of the problems are not taken into account in the past. Thus, in 1999, the CIE held in Kyoto, Japan, the annual meeting, attended by representatives of the proposal, developed by the CIE ...

HB-LED chestnut with two new technologies are increasing the current density and LED datasheet and luminous efficiency. Improve the current density is the use of metal package of energy efficiency LED will be spread to increase the input power, compared to traditional LED 1 ~ 2 W, HB-LED is increased 20-40 times. LED thermal diffusion technology faces two options: one is the LED light-emitting layer (the surface of the LED) and LED price and the metal contact, and LED suppliers and then from the LED inside (substrate side) will produce light-emitting layer removed This design must develop conversion of light transparent substrate; another, LED light-emitting layer and the metal is very close to the body joints, solder contacts with the conductive paste is easy to cause a short circuit, it is necessary to develop new technologies. High t...