In human history, no lighting from the LED so as not yet ripe to be high hopes, but slow development, but also make the LED products too conceptual, the lack of customer base. Even now the government is trying to LED lights as a breakthrough LED support the growth of LED can be either civilian or commercial customer base is still not formed. At this time there is a danger signal: LED manufacturers have to reduce costs as the top priority! Many companies will be bigger and the LED current to maintain the brightness of the same in the case of reducing the number of wick in order to save cost, PCB size or compression, or is to reduce the safety devices and other methods, of course, we have to believe that China"s cost-cutting companies in the natural advantages. Leaving aside the issue of product safety to do so for the impact on the industries concerned, LED in case of no market price on the shuffle into the situation, which is detrimental to the industry, the bulk of the funds went into exacerbate the decline of small and medium enterprises. This is a dangerous situation, on the one hand the development of LED technology will be stagnation and even degradation of the other costs of compression, or cost too much attention can not guarantee the final product characteristics, will not show a large extent on the LED advantage. So I venture that this time the LED industry in the wrong direction.
Now the LED industry in order to open the civilian market, the LED lamps are mostly designed to be replaced, that is a direct replacement for existing lamps. However, in light of the development process, in addition to directly replace incandescent lamps compact outside, little direct replacement model, like T8, fluorescent ceiling is almost the patent, but chandeliers still dominated by incandescent light, LED Why must Replace the road go?
Replacement of existing lighting there any drawbacks to this design?
LED heat poor is well known, the problem will inevitably bring wick life. Existing LED lamp design is often difficult to achieve the required heat, heat in a very demanding field, but a very poor use of the passive cooling method, but mostly air-cooled, air-cooled or even closed. Like some of the lamps in the driver board and aluminum heat sink to add plastic tube to increase the reliability of insulation, silicone heat sink needs to improve heat dissipation. The T8 lamp tube is closed, the wick can only rely on air convection to the tube on the back of the cooling tubes. General internal temperature of these lights will have seventy to eighty degrees. If taking into account the heat and the weight is the problem; take into account the weight, heat dissipation is difficult to guarantee that the current design is the dilemma of choice, yet there is no feasible standard.
LED wick life with increasing temperature and decreased exponentially; electrolytic capacitor temperature is increased by ten degrees lower life expectancy by half; MOS temperature, the resistance increases, loss increases, the temperature will rise (constant current mode), and ultimately burned . Of course, the domestic manufacturers did not give the life of LED lamps, LED publicity when the wick is that life 100,000 hours, but the life of a bottleneck in the system LED driver board, LED wick is not tend to damage the system drive has been hung up.
Also the LED light is a very serious decline, so the lamp life should also consider the visual experience, is how long the lamp brightness decrease to that dark vision on the extent of that life to, the client will consider replacing the lamps, This life is not to give out vendor (or no way to give), but it is very important.
Another is to say, most of the existing LED home lighting limited by the size, protection is difficult to do well in the voltage fluctuations, interference in an area with existing low-power design is a test.
The most important thing is, LED life and corporate life is directly proportional, if the promotion 10 years of LED lamps 2 years on the bad, and six months ago that the company has closed down, the user whether to take the risk?
Spiral lamps in the class interface, LED fluorescent lamp weighs only a fraction of the absence of a heat sink problem, the weight of the fluorescent lamp is negligible, but the weight of the LED lamp is a very serious test, especially the spiral interfaces 7.8W LED lights, its weight is very dangerous, which is what businesses have to consider it?
LED driver board in the general temperature of 70 degrees may be life is only 5 years (home), far from the LED wick 10-year "concept." So compared to the same brightness of fluorescent lamps, fluorescent lamps, even only 1 year life, 1W1 fluorescent lamp is much more than the $ 1W10 is much more cost-effective element of the LED. LED lamps are often damaged, especially the wick is not broke, have to replace the lamp. Calculate because of one-tenth of the driver board have to discard the remaining nine-tenths of the lamp (wick and the heat sink accounts for most of the cost of the lamp), if every company did not do a good job recycling, the customer is not like the product.
Some people may wonder, LED energy-saving products, why should consider the efficiency issue? Here I mention two points, one PF value, one is system efficiency. Since most of the existing LED design are low power, cost pressures are used by the passive PFC (valley-fill), PF may be up to 90, far less than 99 active PFC efficiency at every turn, replaced with LED for countries luminous efficiency of fluorescent lamps is very close to the pressure.
As the existing design of LED lighting (except street lights outside) the majority are low-power, such as 4.8W, 7.2W, etc., the loss of the device accounted for a large proportion of the inevitable isolation is very low, in order to improve efficiency The non-isolation not only to do good in the security design, and efficiency was only 80 or so, far from ideal. And existing LED manufacturer of LED illumination to achieve in the end how much, do not provide accurate values ??are often far less than the nominal value of brightness.
6 light perception
Light perception, that is, the human eye as a sense of the LED light - the visual experience. Because LED lights as a light product, the visual sense is very important. One advantage is the spectrum of pure LED, but it is in the visual top of a very serious disadvantage. The human eye can not observe a single chromatographic long light source, especially in the developmental stages of infants, children, market pure cold white light on the launch of the Eye is not appropriate for children, even without flash, in this in a warm, full-spectrum incandescent lamp is relatively the most appropriate (Ethernet sun as a reference, it is undeniable, the sun is most in need of life) (If you have to understand LED grow lights, you should consider as modulation of plant growth requires light, the human eye is more needed). Of course, LED can be modulated, but more trouble, more professional, need a lot of research theory and data support, many materials are light or LED light source manufacturer or the manufacturer is difficult to achieve a solution provider.
LED is a light source, it is generally grainy LED lamps are more obvious, and its position more concentrated light, visual light, when there will be tingling feeling in the only other high-power light source in general will appear. So the LED light above all need to do better design, in order to achieve the brightness in the case of Bao Zheng, will try to expand into the side of point light sources, to improve eye comfort.
There is a lot of products will do the LED dimming designed to save energy, not to mention the efficiency of low power when the problem because the presence of current in the coils will result in gray-scale changes in the design of the dimming is not continuous, that is in proportion to the process of adjustment, LED brightness will slowly brighten and then suddenly brighten, as the sense of uncomfortable, dimming technology is still a need to develop.
From several aspects, said, LED lighting design requires further development.
LED What are the advantages? In addition to light, high efficiency, energy saving, pollution-free addition there is a very special and often overlooked advantage - low-voltage drive. Mention this point, the LED can be used as a low voltage security lighting to use, the power and wicks, and high-pressure part of the user will not be in direct contact, and avoid some security problems, such as the existing lighting in the damaged when the replacement of the security problems. However, many existing non-isolated mode LED designs for efficiency, making the head is still high, very unsafe.
Compared to existing LED home lighting, power and wick together design, more inclined to switch on the lamp module + power supply + constant separation wick design. Switching power supply can be guaranteed using the PF and efficiency, but also in the protection areas can be easily done very well.
If all of the 4.8W of the light source used in all a switching power supply, the first time the normal operation of the PF, efficiency can be guaranteed, even with line loss (line 23 using the current over 1A, about loss of 0.7W / 10m) is much lower than 4.8W for the loss of existing designs (0.3A14V, efficiency of about 80, loss of nearly 1.5W). Simply put, can be used inside the home to all low-power LED lamps all use a switching power supply, with the copper wick to the top of the low-voltage direct current, even taking into account the length of the alignment caused by loss, but also than the existing program economy.
If the CPU can be used to heat above the use of active cooling design above, the effect is definitely meet the requirements, and to know the CPU temperature is more sensitive than the LED wick. Development of a separate heat sink for the LED die cost is the problem, not whether they have thermal design to ensure the company"s professional qualifications, the use of the CPU heat sink is relatively much better, of course, not so on the official style. Taobao above a DIY model shop, 50WLED the use of the CPU fan.
So, is the efficiency and thermal problems can be a good solution not only solved the life of the impact of replacing them is also very convenient, LED wick is working under the safe voltage, even if not directly touch the dangerous, may be a viable option?
LED does not flash a light source for energy have to be flash, although not conclusive on the eye is good, but after all is lost watermelon picking sesame. 8421 this ratio can be used directly with the switch control how many lights, it touches dimming a good choice.
Nevertheless, the LED market, relying solely on substitution, imitation is get out to go. Power supply design can learn, you can use a certain program, but can never replace the type of lamps occupy the mainstream market (unless there is a great advantage, whether it is effective or the price of light, this LED is not available). LED-style design of the replacement is moving toward a dead end, in the absence of open market conditions, firms again attributed to price factors, desperately cutting costs, in fact, is wrong, a fluorescent lamp 20 (compact, with MOSFET driver, T8 tube about 4 million), while the same 80 cents as long as the incandescent light, fluorescent light such a large price gap, but still occupy the mainstream market, because the fluorescent lamps and incandescent lamps out of a different, more convenient, unique structure, if the original thought of complete replacement of incandescent lamps only, no U tube, T8 lamps and other styles, I believe that fluorescent lamps will still be hard going. So the LED does not depend on the costs to survive, companies need to have a prominent advantage of new LED products, the company must understand the characteristics of LED and the needs of customers, such companies rarely. In the current state of blind competition, many enterprises will swarm all the same architecture, same look, LED lamps in the end how to design, but few people truly want to take this into account.
Therefore, in this market condition, the development of higher light transmission, better materials are light many companies may be a good choice of direction.