2012年5月 – 第12页 – LED Lighting Blog

How to Solve Problems Hide behind the Excessive Development of China types of led lighting?

Recently, regardless of the mainland or abroad, the LED lighting industry is in rapid development, but behind the rapid development Chinese LED lighting products has exposed the lack of core technology and innovative capacity, disorderly competition in the market and other issues. Specific performances are as follows:

Firstly, as for the output value, the current mainland types of led lighting market penetration rate is only 5%. Relying on imports of core technologies and higher overall cost, which becomes a stumbling block to hinder the further development of LED industry. The LED chip is like the engine of a car. Lack of core technology will be directly restricts the development of this industry. It is understood that the LED upstream chip production technology lies in the hands of foreign companies, and the slower the process of domestic technology affects the development of the industry. MOCVD epitaxial furnace and its related technology, on behalf of the most high-end of the LED Street Light industry chain, mainly depends on imports, which greatly restrict the cost control of the LED industry upstream.

Secondly, as to the overall level, the gap between China and the international-class is still about two years. Many developed and developing countries or regions in the world are accelerating the development of semiconductor lighting technology and industry. On technology, China is in the second echelon.

Thirdly, blind investment and the lack of core technology lead to the imbalance development of LED lighting market. Inconsistent quality is also a common issue for LED enterprises. The types of led lighting market exists a lot of small and medium-sized enterprises to produce low-quality products, and the industry pattern is unstable.

Fourthly, with international giant companies entering into the Chinese market, lots of enterprises with core competitiveness in mainland will face the risk of M & A, while enterprises lack of competitiveness may be eliminated directly. If we do not regulate the market, Chinese LED Lights market may degenerate to a wedding dress maker for foreign lighting giant.

According to the analysis of a number of experts, recommendations are as follow:
Strengthen the guidance of government planning on the whole types of led lighting, and carry out enforceable national industry standards as soon as possible, especially related products in the industry standard in the demonstration project, such as street lamps, tunnel lights, display, landscape lights, so that it can provide procurement of local governments and enterprises, standard to follow.

Common problems for LED flat panel light

As for residential LED lighting, LED flat panel light is more feasible than LED bulbs. They are more sophisticated since they have higher light efficiency, better cooling system and more beautiful.

Nowadays, most LED panels are side-lighting lamps. LED chips are mounted evenly on the four sides of them. Most of the lighting from light sources will be reflected by diffusing board mounted at the back of LED panels. They look really good, very suitable for indoor lighting and decoration. However, in point of energy saving and environment friendly, this type of lights are not advisable.

There are a lot of disadvantages of LED panels.

The normal lighting effect of LED flat panel light is around 70lm/W. In other words, this light cannot save more energy than traditional fluorescent lamp. Customers will not choose them just for the purpose of reducing electricity consumption.
As we mentioned before, LED panels need the help of diffusion broads. All of them are plastic products, which will produce toxic gases in high temperatures. Although the normal working temperature of LED flat panel light is much lower than the threshold level of making diffusion broads send toxic gases, this potential risk should not be ignored. Meanwhile, disposing these plastic products is also a big trouble.
LED panels are only suitable for spacious rooms without any suspended ceilings. Therefore, LED flat panel light rarely used in residential lighting applications such as LED Street Light . Usually, they are used as a kind of office lighting.

However, a new type of LED panels appeared in LED lighting market recently, which solved most of problems mentioned above: Back-lighting LED panels. Since all of the light sources are mounted at the back of this type of lights, there is no need to use diffusion broads. And also they are thick enough to use better cooling systems. In many ways, they are more sophisticated than side-lighting LED panels. The only disadvantage of back-lighting LED panels is that they are heavier and occupied more space than side-lighting LED panels.

Overall, LED panel is a big process. They are no longer restricted by traditional design, like LED bulbs. Its form is more suitable for LED light sources.

Embarrassing situations for residential LED light bulbs

Compare with traditional bulbs, LED light bulbs have many different properties:

LED chips are very small. They can be integrated together constitutes the light source of a LED lamp
LED street light cannot work in high temperatures. Normally 70-80 degrees are most suitable working temperature for LED chips. Thus cooling system is very important for LED lights. Cooling systems for high power LED lights, like LED high bay lights, requested high heat dissipation capability. Relatively speaking, small LED lights only need common cooling systems, like residential LED light bulbs.
The beam angle for LED lights is much small than that of traditional lights. Thus in practical applications, light redistributions need to be considered.

Photo above shows a typical form for LED blubs. Basically adopt the design concept of traditional bulbs. However, this design is improper for LED lamps. Indeed, residential LED light bulbs designed as this form are more beautiful than other formed LED tubes. This beautiful appearance is at the cost of the sacrifice of heat dissipation ability. In order to make this shape, designers have to reduce the volume of cooling fins. In accordance with today’s LED manufacturing technique, a LED bulb does not look brighter than a traditional filament lamp with similar power consumption. However, high power LED bulbs is hardly to be realized, since they cannot work in high temperatures. The power consumption of residential LED light bulbs is 3W, 5W and 7W. In fact, LED bulbs within this range perform much worse than 40W-60W filament blubs. It is impossible to use them as main lighting tools. Think about your living room looks like a movie play room during the night, you won’t like this image. They can only be installed in the bathroom or passageway as an auxiliary lighting source.

It is really an embarrassing situation for residential LED light bulbs, and also the main reason why LED bulbs cannot widely spread like LED down lights and LED panel lights. If you have no request in brightness, and you are looking for a method to reduce your outrageous electricity bills, you can try to install some of these LED bulbs in your bathroom, bedroom or even in your living room. But you can expect a bright living environment.

However, salty fish also cab break up unripe. If LED manufacturing technique can get further improvement: more efficient cooling method or higher lighting efficiency, there is no doubt that LED bulbs will replace traditional tubes in indoor lighting area.

China’s power led lamps trading environment has improved

With the western development and living standards improved a lot, it will lead to LED Products market becoming increasingly prosperous in the near future.

In the first grade city, power led lamps in department stores, supermarkets are increasingly luxurious. With the upgrading of the consumption level, people who purchase lamps are no longer just to meet the needs of lighting, but to create a better shopping atmostphere. They are paying much attention to the scene display, store decoration and the products are more and more upperscale, luxury, which is obvious in the area of east, south, north and other places.

The second and third grade cities are risen gradually. In the east and south China region, a number of perfecture-level cities and county-level cities are economically developed, where the professional and stores, decoration quality are rising. For example, in Huzhou, zhejiang, the business area of 5000 square meters of lighting supermatket opened at the end of 2009, and became the first store in Zhejiang Province.

The power led lamps in the second and third grade city are continue to rise up. It provides much convenience for the local lighting consumers. A lot of consumers who originally go to big city to purchase light are directly choosing to buy at local. Also, it stimulate the local LED lamp consumption.

With the Project launch of the “China Green Lighting Project”, the 13 departments of the State Economic and Trade Commission jointly organized and implemented aiming at saving energy, protecting the environment, improving lighting quality activities. “Green light” refers to highg efficiency, long life, sacurity and performance through the science of lighting design to improve the way that people work, study, living conditions and quality purposes, therefore, creating a efficienty, comfortable, safe, economical and beneficial to the environment, in order to reflect the lighting of modern civilization.

At present, LED street light are on the pioneering phase in the market. The price is a little high, and unknown to the widely customers. But the market potential is huge. On account of its many advantages, for example, eye protection, energy saving, environment protection and long life. It can be estimated that in the near future, with the declining cost of high power LED lamp, the market of power led lamps will have a broad development.

Shape designs for T8 LED light tubes

T8 is a code represents a type of tubes with diameters of one inch. T8 LED light tubes are mostly used LED tubes at present. Although the light efficiency of LED light sources is much higher than before, there are still some difficulties in replacing traditional fluorescent tube directly by LED tubes. In accordance with lighting standard of fluorescent tube, a 36W traditional tube should at least have a luminous flux of 2400lm. At present, among T8 LED light tubes, the highest luminous flux is around 2200lm (with a power consumption of 21W). However, cooling system of this kind of tubes cannot be contained within semi-circular pipe but trapezoidal pipe which provides larger spaces. In today’s manufacturing technology, it is impossible to create a T8 LED tube with trapezoidal-shaped cooling components. Cooling system will be the bottleneck for high power T8 LED tubes. According to present lighting efficiency of LED lights, T8 LED light tubes with a luminous flux more than 2000lm will suffer cooling problems. This type of lights cannot work for a long time and more prone to failure. Commonly used T8 LED tubes have a luminous flux of 1300lm-1500lm. This type of LED tubes cannot be used to replace traditional fluorescent tubes. This is a main reason why LED tubes are hardly to be accepted by customers. Many buyers complained that their rooms looked much dimmer than before.

In addition, LED tubes tend to follow the step of fluorescent tubes: becomes more and more thin. T5 LED tubes started to emerge in lighting market in few past years. However, this kind of herd behavior is totally wrong. It is an inevitable trend for fluorescent tubes, since a thinner tube can dramatically improve the lighting efficiency of a fluorescent tube. But situations are totally different for LED tubes. The thinner the tube, the harder for the heat dissipation. Meanwhile, spot phenomenon is inevitable if light sources are too closed to the cover, which will reduce light transmission ability of the cover, and consequently the high lighting efficiency of LED lights.

Designs of T8 LED light tubes should not be restricted by traditional ideas. Normally, places in which tubes are installed have larger space. It is uselessly to use thin LED tubes, just for a beautiful view? It is unnecessary. Our design object is to satisfy customers’ brightness requirements together with suitable cooling systems.

Filament lamps should not be replaced by super high power LED though power consumption judgment (2)

LED lighting technology is enjoying a rapid development. 15 years ago, a LED street light with a power consumption of 1 watt can only sent out lights of 30lm. 15 years later, a one-watt LED light can have a luminous flux around 100lm (super high power LED). While a 15-watt filament lamp have a luminous flux about 180lm. The development of LED is so fast that it is really hard to replace a 15-watt filament lamp by a LED light with fixed power consumption. On the other hand, power consumption is a parameter used to present electrical energy converting conditions. LED components with high electrical energy converting ability can have a higher luminous flux only consuming very little power.

Luminous flux, optical spectrum is photometric data typically used to present lighting effects. Why people choose to use power consumption to present the brightness of traditional lamps instead of these more accurate photometric parameters? In the early age, when filament lamps had just been invented, the brightness of a 1-watt filament lamp is approximately equivalent to then light from one candle. Gradually, people related power consumption with brightness. Same situations happed in fluorescent lamps. Nowadays, LED lights have taken the place of traditional lights in many areas. It is improper to represent brightness though power consumption. As for LED Grow Lights, brightness of which is hard to be related with power consumption, can only be clearly represented by more scientific photometric parameters mentioned above.

As for light sources of LED lights, luminescence ability can be represented by the light distribution curve measured on their surface. Luminescence ability of the entire LED lights, the light distribution curve should be measured in front of projectors. If two lamps, no matter what type of lamps they are (super high power LED or traditional filament lamp), they will have same brightness if the light distribution curve measured before the entire lamp is similar. Brightness measured though illuminometers are usually different from brightness felt by our eyes. Under circumstances that accurate luminous flux is not necessary, brightness can be roughly represented by the measuring results from illuminometers. Since this method is cheap and easily to be realized.

Investment Opportunities of shop LED Lighting Should Be Judged Rationally

During current years, various aspects of China’s LED industry are packed with industry and non-industry investors and nearly 4000 enterprises found only in the shop LED lighting application side in the past two years. Flowers are flourishing before the spring really comes, which is quite appropriate to describe the status of this industry. On one hand, market participants become more and ambitious; on the other hand, the industry chain develops unevenly. What investment opportunities lie behind this glittering industry? PV industry and wind energy investment boomed a few years ago and now retreat. What lessons can be left to this wave of LED Lights market participants?

Semiconductor lighting is recognized as one of the most promising technology of the 21st century, opening the third revolution in shop LED lighting of the human society, bringing huge economic benefits. Over the past decade, the average annual growth rate of the global LED downlight market’s scale is over 20%; the growth high brightness LED market is more rapid, the average annual growth rate 46% from 1995 to 2005. The size of the market in 2008 reached 5.1 billion U.S. dollars, accounting for the ratio of the LED market more than 80 percent growth from 40% in 2001, with a conservative estimate that in 2012 the market size is expected to reach $ 11.4 billion.

In this industry chain which is full of highlights and value, the upstream firm took more than 70% of the profits, which is a capital-intensive, high technology content, high rate of return link. The core patented technology of upstream is concentrated in Japan Nichia (Nichia), the United States Corey (Cree), Germany Osram (Osram), and a small number of overseas giants, belong to a typical oligopoly business (Schedule). In the fields of epitaxial wafers and chips, the U.S. and Japanese companies take a monopoly advantage.

Shop LED lighting growth in the mainland should follow the bottom-up path. To think about the early industrial mode, it may be worth LED domestic enterprises to seize market opportunities and grow their own strength.

The LED street lighting market in the turbulent perhaps is a new feast for Chinese manufacturing enterprises. PE should be rational in this area to avoid irrational thinking of the investment in solar energy industry market. On the basis of market-oriented principles to select the appropriate enterprises, it will be illuminate the manufacturer and PE future.

Filament lamps should not be replaced by super high power LED though power consumption judgment (1)

“What is the equivalent LED lamps for xx watt filament lamps?”. “We replaced an energy-saving lamp by a LED down light with much less power consumption, but coming out that it looks much dimmer than before. Should we use a super high power LED instead?” these are questions that would be asked by customers mostly. In fact, this comparison criteria is inaccurate. We cannot judge the brightness of a LED lamp and a filament lamp just tough their power consumption. Traditional lamps like filament lamps and fluorescent lamps, they usually send out a full space light due to their internal constructions. In practical applications, no matter LED lights or traditional filament lamps, all of them will be used together with other reflecting tools, like projectors or other lamp covers with reflecting function. Lamp cover plays a role of light re-distribution. This re-distribution will be different according to different lamp covers used. For instance, straight tubular fluorescent lamp can be mounted either by lamp covers with reflection function or by lamp covers without reflection function. However, the lighting effects are totally different for them, as well as effective luminous flux. Thus, it is improper to compare LED lights and filament lights just though power consumption. To what subject you are comparing? Filament tubes without any other auxiliary components? Filament tubes only mounted by ballasts? Or filament tubes with full set of reflecting components including projectors? This kind of view makes no sense without any premises.

It is unreasonable to compare LED lights with traditional filament lamps just though power consumption. Traditional lighting sources have relatively stable technology, power consumption is basic a linear relations with luminous flux. Thus power consumption can present brightness to some degrees. While this linear relations cannot be established between LED lights’ power consumption and their luminous flux due to the unstable of the photosynthetic efficiency value of LEDs. Even for super high power LED, there is no such relation. With the rapid development of LED lighting technology, the improvement between the power consumption and the luminous flux will be continued. Thus it is impossible to give out a certain relations between them in near future. Maybe after several years, this problem can be solved. Then we can compare the brightness of LED lights and traditional lights by judging power consumptions.

Does high efficiency white LED look brighter than filament lamp in same luminous flux? (2)

In previous article, we mentioned about the concept that under different circumstances people feel different light brightness. Even these lights come from the same lamp. The most important reason is that radiations energy will change the brightness of this light in our eyes. For example, if the ground and walls are blue. In same luminous flux, high efficiency white LED looks much brighter than filament lamp. In the optical spectrum of white LED lights, the peak value of the light intensity distribution is between 466nm and 485nm (blue-ray). Thus most of the light coming from white LED lights will be reflected by the ground and walls. On the contrary, if the ground and walls are red colored, more light from filament lamps will be reflected. In such condition, we cannot simply conclude that high efficiency white LED looks brighter than filament lamp in same luminous flux. That is all depends on surroundings.

So far, we have concluded two different results. One is from the measurement result of illuminometer and the other one is from our eyes’ feeling. Differences between them are caused by the unscientific measuring method. In the matter of fact, using illuminometers to measure luminous flux is not as accurate as we all considered. The light measured by illuminometers is light directly coming from light sources, and the light caught by our eyes is mostly from the ground. They are totally different objects. But why designers and engineers still use this method to measure the luminous flux? Firstly, this method is relatively easy compare to other methods. Secondly, it can provide a rough measuring result in most conditions. Finally, illuminometers are much cheaper. These three advantages make illuminometers frequently used in situations that accurate brightness data is not necessary. Many design houses for residential decorations use this method to reduce their cost.

In conditions that LED high bay light intensity results are required, methods measuring light intensity are more accurate. Engineers can measure the light intensity on the surface of the ground and walls directly. Values measured by this method will be much more closed to results perceived by human eyes. Brightness meter is an optical instrument typically used to measure light intensity. But this instrument is more expensive than illuminometer and Eneltec LED Flood Lights. In commercial field, brightness meter is not so popular as illuminometer.

Does high efficiency white LED look brighter than filament lamp in same luminous flux? (1)

Does high efficiency white LED look brighter than filament lamp in same luminous flux? This is a rather complex problem. It involves properties relate to human optic nerve system, and also some optical concepts. From the view of the optical measurement, as long as different testing LED lights have same luminous flux, they should look like the same in human eyes. No matter what color they are. However, if the testing object is light radiance, the result will be different. Tow bundle of lights with same radiation energy but different color temperature, will look different in human eyes. A lot of technician did not take these differences into account, leading to the inaccuracy of their testing results. In their opinion, high efficiency white LED street light has been proved much brighter than filament lamps in all conditions.

If using luminous test to compare the brightness of high efficiency white LED and filament lamp, there is one point needs to be noticed: the object should within the same surroundings (consider the radiation energy from the ground reflection), otherwise, the result will be inaccurate.

When we design an indoor led lighting products application, the commonly used instrument for testing light intensity near the ground is illuminometer. However, even for the same lamp with same projectors and luminous flux, light intensity near the ground will be different due to different ground conditions. Similarly, we will recognize them as different light since they have different brightness. Illuminometer is a type of instrument typically used to measure light intensity though the optical energy caught by the sensors mounted on its head. When we measure the light near the ground, we are only measuring the lighting coming from light sources. What about other light reflected by the ground and walls? After absorbing and diffuse reflecting by the ground, some light energy converts into radiation energy. The amount of energy all depends on what material the ground and walls used and the construction of the entire room. In other words, light caught by illuminometer is just part of what we have “seen”. That is reason why when illuminometers gave out same measuring result, we feel different light brightness.

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月份：2012年5月