标签：LED lightings

The 50th anniversary for led lightings invention: the great people and the great invention

50 years ago now, Nick HolonyakJr — the United States Ge Corp ( General ElectricCany, GE ) , an ordinary researchers, research produced the world’s first red LED, and opened the LED Panel Light history. Now 50 years past, LED industry really like he prophesied before that ” LED will have many different colors of light, incandescent lamp, the future will be replaced by LED”. Now, in the low carbon energy trends, LED industry has become a country competing development products. As the fourth generation light source, LED has been widely used in a variety of display and illumination field, also lies in that in people’s life to bring a new round of lighting revolution.

The 50th anniversary for led lightings invention

On the occasion of the 50 anniversary of the LED method, we cannot forget that in 50 years of development of the road, the promotion of the LED step by step towards the revolutionary breakthrough of those great scientists and their great invention.

Red led lightings inventor —Nick HolonyakJr.

The invention in 1962 of LED Nick HolonyakJr., he was only the United States manufacturers Ge Corp ( General ElectricCany, GE, also known as the singular ), just an ordinary researchers. He created the first red LED, but he also believes that the future can emit light of the other wavelength, it means that LED will have many different colors of light, future incandescent light must be replaced by LED.

Yellow light inventor —-George Craford LED

George Craford the United States famous electrical engineer, in the field of led lightings contributions made by the most prominent. In 1972, Dr. Craford invented the yellow light and red and orange light LED. His graduate and doctoral students are enrolled in the United States of America Illinois University, specializing in physics, who obtained master’s degree 1963, doctorate in 1967. After graduated, he joined Monsanto chemical company, the company is the world’s first mass production of light emitting diode ( LED ) company, his team in 1972 developed nitrogen-doped GaAsP ( GaAsP ).

The father of the OLED – Deng Qingyun

In early 1979, Dr. Deng found OLED. That’s one evening in 1979, Dr. Deng is on the way to home. He suddenly thought of something forgotten in the laboratory, then returned to the laboratory. He found in the dark with a bright thing, that the original is an experimental organic battery in the light. Thus began the research on OLED.

United States indicate: led lightings can inhibit urban crime

Criminal psychology–the general term for the influence and domination of crime perpetrators from various mental activities or psychological factors. The criminal mind is the intrinsic motivation of the crime and the dominant power。 It is the crime Criminal Minds external performance. The movie “Criminal Minds” (Criminal Minds) is a psychological suspense thriller drama, a group of elite pooled analysis of the country’s most intractable the comic crime cases criminals psychology and predict their next step before they once again have violence action.

led lightings, United States indicate: led lightings can inhibit urban crime

The American Austin City Police Department and Austin Energy Energy Board cooperation protect the residents of the city.Since a significant increase in violent crime rate in mid-2011, the two institutions plan fitted with led lightings, the prevention of crime in the U.S. city of Austin, the three most dangerous locations.

Austin Energy spokesman Carlos Cordova, announced that a well-lit place is usually not an offense where there has been committed, because when you want to do bad things and nobody seen.

In accordance with the requirements of the city’s Police Department, Austin Energy erected 25 LED lights. The new LED bulb and high quality LED Flood Lights illumination is brighter than the old bulbs. Cordova said under good lighting environment, people can be assured of recreational activities, and no need to worry about security issues.

Austin, 8th and 9th of the street lighting test results are very successful, this lighting project is one of a series of policies against urban crime. The growth of violent crime by 15 percent from 2011 to January 2012. But until July, violent crime only grow by 7.8% next city a larger project, 70,000 lamps will be updated by Austin Energy budget expenditures.

It is reported that this new led lightings products can reduce the crime rate. Among each countries, the earlier start to use is Japan, called LED guard against light, which has been gradually applied in street alleys to replace fluorescent lamps mainly traditional street lights.

In addition, studies have pointed out that the blue light can make people more calm, and some of the LED light will also guard against taking blue, white separate configuration.

The following development trend of high-brightness LED lightings

How to get the LED lights to support the larger current

In recent years, the industry is very positive for just one to achieve a considerable brightness LED R&D and technology in this regard will fall on. How to make the LED support a larger current. But this result is still far to meet the market expectations. So the goal is more than 10 times and the current conduction to the LED components. So when the LED lightings area size can be expanded to 1m square meters, the following work is how to make the current value reach  350500mA. Because the drive voltage is over 3V, so we can have a 1m square meter of 1W of electricity flowing into the chip area.

The following development trend of high-brightness LED lightings

In the aspect of luminous color rendering, although such a large power input to the GanLED, yet the devoted formation of heat, so the LED products will overheat, which will directly affect into the LED color rendering results. The basic characteristics of the temperature rises, the luminous efficiency will drop and cause CRI bias, so how to effectively release a large number of exothermic heat technology becomes a key, so the LED lightings mounted on the thermal conductivity, heat capacity becomes a very important issue, at present most of the use of divalent metal or ceramic.

Short wavelength to bright high-energy quantitative Reed from the light to enhance the luminous efficiency of phosphors.

From Blu-ray GaNLED has been successfully developed high brightness degree of the green LED start although the long wavelength of the R&D trends, but because InN mixed crystal ratio increased which led to deterioration of the crystalline, and is now gradually being the industry to give up. The other hand, such as laser substitutes new applications R&D also began to consider the industry and the short wavelength of the R&D is actively processing. Recently some Japanese Lab at the University has successfully developed a 250nm of the LED tube, but the practicality is still to be thinking, because the human eye is about 380nm wavelength acceptance, so if the wavelength more than 380nm short-term, which is unable to produce visual LED lightings or low output.

 

 

The development trend of high-brightness LED lightings

With the improvement of the LED lights performance, the applications of market grow rapidly and extensively. The future development of high-brightness LED grow lights market will be more rapid and extensive growth. Among it, the most obvious penetration rate is white LED lightings. In the late of 90th century, the context of environmental protection and energy saving by market expectations, and also stimulate the industry to quickly research and development the relevant technology. For now, the white LED applications, including mobile phone LCD back-lighting and automotive interior lighting, just these markets already account for about 25 percent of the overall LED sales.

The development trend of high-brightness LED lightings

On the other hand about the part of the lighting applications in the realm. General lighting of the building often accounts for 20% of the entire electricity consumption in Japan, the 1990s has been more than an annual $ 100 billion kWh. So the expectations for a new generation of energy-saving light source is quite large, but unfortunately so far, the white LED can only use a very small range. Like a small white LED lightings 5mm, it is not like a light bulb or fluorescent, only one will be able to use of the environment required for the amount of light. Therefore, if the LED can step into the architectural lighting, you need a bigger breakthrough in the overall technology job.

The basic structure of the high-brightness white LED

The white LED is basically in two ways. A multi-chip type, a single-chip type. The former is a three RGB LED package together at the same time making it luminous and produce white light, which is blue or violet. UV LED as the light source used in conjunction with the phosphor to produce white light. The former way, you must combine a variety of characteristics of LED driver circuit is more complex, only complex, only one kinds of the type of the latter single-chip LED, circuit design is relatively easy. Single-chip type is further divided into two categories, a Blu-ray LED lightings source, the other is to use the new-ultraviolet and ultraviolet light. Now, most of the white LED tubes market is the blue LED with YAG phosphor.