White LED lighting over color LED applications

In many families, institutions, government and industrial applications, high brightness (HB) white LED (light-emitting diode) is rapidly replacing incandescent. In the past year, the white LED lighting system in the total lighting applications accounted for more than 50%, and ultimately more than the color LED applications, color LED applications are mainly driven by the aesthetic needs of color lighting. The new driving force for the growth of white LED lighting is quite simple: lower energy consumption leads to much lower electricity bills.

In many cases, the higher efficiency of LED can reduce power consumption by as much as 88%. They also greatly reduce the amount of carbon dioxide emissions caused by electricity generation and transmission of electricity for lighting. According to Strategies Unlimited's research, by 2012, the total high brightness white LED lighting market is expected to be more than 5 billion U.S. dollars, corresponding to 2009 to 2012, the compound annual growth rate of 28% (CAGR). This is just the beginning, because the luminous efficiency in LED to improve the speed of commercial / residential lighting market from incandescent lamp, fluorescent lamp and high pressure sodium lamp to high brightness white LED change at the same time, LED from the commercial point of view will become even more cost-effective.

According to some calculations, the shift from traditional incandescent and fluorescent lamps to LED lighting can save up to 10% of total global energy consumption. As people try to reduce the amount of carbon dioxide produced by power generation, the potential for a 10% reduction in global energy demand has played a significant role in the shift.

What factors support such a huge growth potential? First of all, the luminous efficiency of the generation of LED is 10 times higher than incandescent lamp, fluorescent lamp and high pressure sodium lamp (HPS) more than two times, which greatly reduces the required light output (lumens to measure the necessary power). With the further development of LED, they will continue to improve the efficiency of power transmission, and is expected to double in the next few years.

Second, in a world that is very concerned about environmental protection, LED lighting does not need to deal with, contact and remove the common toxic mercury vapor in fluorescent lamps. Today's cold cathode fluorescent lamps (CCFL), which are used in most residential lighting systems, contain up to 5mg of mercury, while larger ones contain more mercury!

Third, incandescent lamps need to be replaced every 1000 hours, while the sustainable use of fluorescent lamps for up to 10 thousand hours, compared to LED life expectancy of more than 100 thousand hours. In most applications, this allows the LED to be permanently embedded into the final application without the attachment.

Examples include indoor and outdoor commercial and residential lighting, such as street lights, indoor and outdoor industrial lighting, and lighting in hazardous environments such as power plants and refineries. Some applications (such as refineries) run 24 hours a day, LED will continue to use for up to 11 years, which means that they will never need to change. In addition, LED is smaller and flatter than several other types of lamps and can be manufactured in very flat dimensions, so they can be permanently placed inside and outside the application.

The small size of the LED also makes it possible to make the reflector in the LED housing more elaborate, thus focusing the light more efficiently. White LED provides pure "full spectrum" white light, there is no gap in the chromatography, thus the need for reliable visual acuity task, it can be very easy to see clearly. For example, look at the color line, read the color mark, or distinguish between water vapor and flame smoke. On the contrary, it may be difficult to accomplish the same task in an orange high-pressure sodium lamp lighting environment, because it is not possible to distinguish colors in this lighting environment.

Compared with the human eye can perceive changes, LED can also be much faster than the speed of light and switch on / off, which greatly reduces the power consumption. LED lighting can be switched on or off, until it is needed, and then immediately connected to the maximum light intensity, while the fluorescent lamp or high pressure sodium lamp takes up to 30 seconds or longer to achieve maximum light intensity.

However, one of the biggest challenges facing lighting designers is how to optimize the benefits of the latest generation of LED. Since LED typically requires an accurate and efficient DC current source and a dimming method, the LED driver IC must be designed to meet these requirements in a variety of applications. Power solutions must be efficient, robust, very compact and cost effective. That will drive the lighting transition from incandescent lamp, fluorescent lamp and high-pressure sodium lamp array to the LED, the fastest growing applications will appear in the general internal / external lighting applications, because in this type of application, the return is the biggest power savings.

Such as small size, long life, low power consumption, easy to light and fast turn on time and other benefits have accelerated the high brightness LED in industrial and residential lighting and many other lighting applications have been used. Long life and small size of LED for the introduction of new configuration in a variety of applications possible, these applications include front white LED array and lighting to illuminate the entire campus more complex systems in the refrigerator. The following figure shows the Verrazano bridge in New York,, the bridge is completely high brightness LED lighting. The high efficiency of LED greatly reduces the required power, and their long life and durability are especially important in relatively harsh marine environments.