LED lighting needs to take the road of independent innovation

The global advocate of low-carbon life, energy-saving carbon reduction LED semiconductor lighting has become the "darling" of the times. LED is a new generation of environmentally-friendly light sources that attract worldwide attention. Its advantages of high brightness, low heat, long life, and non-toxicity are known as the most developing green lighting sources in the 21st century. At present, China has included semiconductor LED lighting in its mid- and long-term technological development plans. It has initially formed an industrial chain for epitaxial wafer production, chip preparation, package integration, and LED application. Under the current opportunity, independent innovation is particularly important. Prof. Zhao Haitian of the School of Architecture and Urban Planning of Shenzhen University used LED lights to analyze the feasibility of independent innovation through question and answer.

Is independent innovation feasible?

The government-supported semiconductor lighting industry is an opportunity for great development. Many companies are optimistic about the development space of this sunrise industry, especially the obvious advantages of semiconductor outdoor lighting, many companies still do not understand the characteristics of semiconductor road lighting production. , For a time: "a hundred schools of thought contend, a hundred flowers" products have been pushed to the market.

At present, LED applications and R&D are mainly replaced by LEDs and traditional light sources. Almost all LED manufacturers follow the design concept of traditional street lamps and pursue high-power LED street lights of tens of watts and hundreds of watts in order to meet current HPS lamps. The modeling and installation methods are the same or compatible, resulting in almost all LED street lamps and installation methods being designed and manufactured based on the standard of "snake head (plate and snake head) lamp" suitable for HPS light sources, rather than research and development based on the laws of LED light emission.

Is simple alternative feasible?

Simulations, counterfeiting, and various conventional “snake head” shapes have been made alongside current day-to-day street lighting. From the perspective of the existing manufacturers of LED street lamps in China, most of them have not produced street lamps, and the technical requirements for the production of street lamps have been blurred. Mutual reference, imitative, in the traditional traditional "snake head" shape of the majority, the weight of the LED street lights and wind resistance affect the transformation of the street lamp installation, in the optical distribution and maintenance requirements compared with its conventional gas discharge lamp lighting more difficult In particular, the owners of the direct users strongly reflected the difficulties in application promotion.

Glare problem. Glare is caused by the high brightness of a lamp or luminaire directly entering the field of view. The severity of the glare effect depends on the brightness and size of the light source, the position of the light source in the field of view, the direction of the viewer's line of sight, the level of illumination, and the reflectance of the room surface. There are many factors, among which the brightness of the light source is the most important. No matter if it is high-power or low-power, if the light distribution is not good, there will be glare. Now many LED lamps use transparent masks in order to achieve light efficiency. The effect is very poor.

Invalid lighting problem. At present, most public spaces are corridors, walkways, parking lots, toilets, elevators, and roads. It is usually transmitted through long periods of illumination, and these places are sometimes empty, and electrical energy is consumed in vain. So the most power-efficient technology is not the wattage of the lamp, but how to make the lamp smarter and more human. When no one is using it, it can go into "sleep" state, and someone's appearance will slowly be awakened.

Visibility issues. The zebra crossing effect and the environment with serious air pollution and rainy and foggy weather cause the phenomenon that the lighted ground is not bright enough. Therefore, the most important main attack is to reduce the energy consumption without affecting the ultimate goal of lighting visibility. The direction is to strive to increase the overall uniformity of the lighting. With a good total lighting uniformity, the average brightness of the lighting can be appropriately reduced, so that the same visual effect of recognizing objects can be achieved, and at the same time, energy saving and consumption reduction can be achieved.

The facts show that the replacement of HPS light sources with LED light sources is not a change in the lighting method, nor can it solve the problems with high-position light lighting.

What are the new problems with LED street lights?

Light efficiency problem. Insufficient understanding of road lighting requirements, scientific point source optical light distribution difficulties, and importance of color temperature in road lighting are neglected, easily causing glare, zebra effect, and in the environment of severe air pollution, rain and foggy weather, causing lights to shine The ground is not bright enough.

cooling problem. No matter if it is a single point or multi-point light source, there is a problem that the heat dissipation is difficult. One street lamp with 250W high-pressure sodium lamp, due to more mature technology, heat control is very good, even if the work of 5,000 hours, the light failure is still small, under the same conditions, high-power LED street lamps, due to heat problems are not easy to solve, light decay is greater, Luminous efficiency will drop to 30%. If you want to increase the efficiency of light with the method of increasing the voltage and current, it is easy to cause the phenomenon of LED chip damage.

Life problem. LED drive power instability is the industry consensus, in fact it is dragging the LED lighting industry, because the driving power is an important part of the LED street light, its failure will lead to the failure of the entire light. Due to the harsh environment of outdoor work, the life of some of the components of the power supply becomes the bottleneck of the life of the driving power supply or even the entire street lamp.

Weight problem. The high cost of LED street lamps is not conducive to popularization. Although the problem of heat dissipation of LED street lamps has been initially solved, the excessive price and excessive weight of the lamp head will still hinder the popularity of LED street lamps.

What is LED's independent innovation?

One is the research of the upstream chip technology in the LED. As the world's largest lighting market, China's weakest middleware LED technology has become a serious injury. Many domestic manufacturers lack core technologies and invest very little in innovation and research and development, leading to the long-term monopolization of key LED technologies. Without technology, there is no way out. Simply using an irresponsible and irresponsible mass production movement leads to a continuous overcapacity and quality imbalance.

The second is the study of LED related standards. As an attractive new lighting product, how to use the LED light source to meet the requirements of the application is a major issue for LED lighting products. To solve this problem, we should start with understanding the standard system of existing lamps and clearly define the basic principles of the lamps. When we look at the characteristics of LED lamps in a scientific way, we will understand that the existing lamp standards have covered LED lamps. Due to some characteristics of LED luminaires, additional requirements for LED luminaires are also required to establish special requirements for LED luminaires.

What restricts independent innovation?

Impetuosity is the natural enemy of independent innovation, and it is too quick and immediate.

Impetuous product performance. At present, LED applications and research and development mainly use LED and traditional light sources for simple replacement, follow the traditional street lighting design ideas, LED light sources simply replace the traditional light source, can not play a good LED advantages.

Impetuosity in research performance. It is difficult to adapt to the ever-changing market environment by relying on the technology research and development model of enterprises alone. It must be integrated with all enterprises and institutions in the upstream and downstream industries to establish an “innovation chain” for R&D and even the entire industry in order to promote large-scale development. Technological innovation.

Impetuous performance in the media. Many media are unable to truly grasp the development trend of the industry. They like to exaggerate the development of the industry. As a result, companies in the industry cannot truly understand the state of development of the industry and make mistaken judgments.

Therefore, LED industry is a strategic emerging industry, there is still a long way to go, in the process of industrial development will naturally encounter systems, ideas, technology, markets and other aspects of the problem, both the need for their own efforts, but also need each Give attention, attention and support to the aspect. LED industry is an industry with great development potential. We are confident to face challenges, be creative, strengthen cooperation, deepen application, guide the healthy and sustainable development of the LED industry, and promote China's LED industry to become bigger and stronger.