Songhao Liu, an academician of Chinese Academy of Sciences (CAS) and the famous optics and lasers scientist professor, recently stated that LED lamps will replace incandescent bulbs soon, occupying the lighting market. He believes that the key technical constraints may hinder the development of China LED industry.
LED to be Popular
Compared with conventional incandescent lighting, LED has many advantages: first, it is a solid device, without filament and glass bulb, so it is not afraid of vibration and brittle. Its service life is up to fifty thousand hours. Secondly, the power consumption of LED is only 60% of incandescent lamps', the LED lamp does not contain mercury, lead and other hazardous substances, and so it is conducive to recovery. Third, LED is DC driven, unlike incandescent lamps powered by AC; it will not appear high frequency flicker and helps protecting the eyes. In addition, LED required relatively small voltage and current, suitable for occasions lacking power, such as the mines and the wild.
According to the introduction of Songhao Liu, all countries are increasing the investment in the development of LED industry. The U.S. Department of Energy issued a "solid-state lighting plan" in 2012, which predicted that 55% of incandescent and fluorescent lamps will be replaced by LED lights by 2030. And South Korea aims to become Asia's largest producer of photoelectron and replace 30% of the traditional lighting with LED lighting in 2015.
China established an inter-departmental National Semiconductor Lighting Project Coordination Leading Group, who made a clear goal that China LED industry scale will reach 500 billion Yuan in 2015, the luminous efficiency of white LED is up to 150 - 200 lumens / watt, it is estimated that 100 billion kilowatt hour of electricity, 350 billion tons of standard coal and 100 million tons of carbon dioxide, sulfur dioxide and dust emissions will be reduced every year, 200 million new jobs will be provided. Among them, the Pearl River Delta region takes up 42% of the national LED market.
Technological Disadvantage May Constrain the Development of LED Industry
Songhao Liu introduced that LED industry still is a mess with different standards. At present, Guangdong has started standard optical components plan to introduce Military Standards into LED industry, and the provincial inspection stations with national qualification test the products on a regular basis, coupled with the uniform standards, the development of LED industry will become more standardized.
There is a common problem in LED lighting products on the current market. The brightness begins to attenuate after a period of time, which is obstruction for the large-scale application of LED. Songhao Liu thinks that MOCVD technology is the potential weakness of the development of LED industry. MOCVD stands for "metal organic chemical vapor deposition", which is the key technology to prepare the PN junction on LED. Because the manufacturing of relevant equipments is very difficult, domestic LED enterprises mainly rely on importing. In recent years, domestic MOCVD equipments begin to come into market, but it still takes a long time to achieve mass production.
