LED lighting reliability assessment of the problem to be solved

At the same time, there are many forms of LED lamps and lanterns, and the vast majority of LED lamps and lanterns are not interchangeable, so that the life of different LED lamps can only be determined by the relevant life evaluation. At present, the use of accelerated tests to predict the life of LED lighting products is a very important means, the main principle is to make the device work stress level than the normal use of the experience of stress must be high, effectively stimulate the exposure of product failure, so as to shorten by the specific failure mechanism.

According to reports, life performance measurement and evaluation of traditional light sources have been standardized, because of its short life and light source are interchangeable, whether incandescent lamps or energy-saving lamp bulb is broken for a lamp will not affect the continued use, it is generally not the traditional evaluation of light with life. But the LED lighting products have a long life, and it is not appropriate to evaluate the life of the products by collecting data for a long time.

At the same time, there are many forms of LED lamps and lanterns, and the vast majority of LED lamps and lanterns are not interchangeable, so that the life of different LED lamps can only be determined by the relevant life evaluation. At present, the use of accelerated tests to predict the life of LED lighting products is a very important means, the main principle is to make the device work stress level than the normal use of the experience of stress must be high, effectively stimulate the exposure of product failure, so as to shorten the normal time of device failure caused by the specific failure mechanism.

But for LED lamps, because of its complex structure, many factors affect its life. For example, the life of the LED light source, LED drivers and the environment will affect the life of the lamp. And because the technology is still in continuous improvement, LED lamp life should be relatively perfect after the technology is more reasonable evaluation. However, before the relative improvement of LED technology, it is necessary to establish a scientific evaluation method and evaluation model of LED lamp life.

In addition, the definition of the life of the LED lamps have yet to be discussed. Because of the characteristics of LED lamp and traditional light source single luminous body, it is composed of a plurality of luminous bodies and light, there are differences between the color light, the color temperature and color change color etc. in the lamp life definition should also be taken into consideration.

For example, a LED lamp used for a period of time, the luminous maintenance rate is still as high as 50% or its performance is higher than the initial efficiency of 70%, but the color may not be used to meet the requirements, then in accordance with the actual situation, should assess the end of lamp life, but according to the definition of the "research and Development Alliance national semiconductor lighting industry engineering technical specifications" are recommended, the lamp life is still not the end, you can use. Zou Nianyu believes that the definition of the life of the LED lamp, not only to focus on the maintenance rate of light, but also need to consider the color temperature, color rendering and other related indicators. Zou Nianyu said, many researchers at home and abroad are committed to the development of new LED lamp life evaluation method, but so far has not established a convincing whole lamp life evaluation model.

DOE reported that the industry is still not a very viable way to assess the expected life of lamps. Although the standard of lumen maintenance testing and planning has been improved, it is difficult to quantify the driving life and system color maintenance. The DOE report is intended to define existing standards and planning standards, and analyze the limitations of existing definitions of LED lamp performance. The report notes that the main problem is: the existing method of lumen attenuation as the only elimination mechanism LED lamps, there is no standardized assessment method to solve the problem of components other than light source.