Friday, May 4, 2012

100 th Post - Dedicated to Inventor of LED Nick-Holonyak-Jr


Nick Holonyak, Jr. (born November 3, 1928, in Zeigler, Illinois) invented the first practically useful visible LED in 1962 while working as a consulting scientist at a General Electric Company laboratory in Syracuse, New York and has been called "the father of the light-emitting diode". He is a John Bardeen Endowed Chair in Electrical and Computer Engineering and Physics and Professor of electrical and computer engineering at the University of Illinois at Urbana-Champaign where he has been since 1963.


In addition to introducing the III-V alloy LED, Holonyak holds 41 patents. His other inventions include the red-light semiconductor laser, usually called the laser diode (used in CD and DVD players and cell phones) and the shorted emitter p-n-p-n switch (used in light dimmers and power tools). He helped create the first light dimmer while at GE.
In 2006, the American Institute of Physics decided on the five most important papers in each of its journals since it was founded 75 years ago. Two of these five papers, in the journal Applied Physics Letters, were co-authored by Holonyak. The first one, coauthored with S. F. Bevacqua in 1962, announced the creation of the first visible-light LED. The second, co-authored primarily with Milton Feng in 2005, announced the creation of a transistor laser that can operate at room temperatures. Holonyak predicted that his LEDs would replace the incandescent light bulb of Thomas Edison in the February 1963 issue of Reader's Digest, and as LEDs improve in quality and efficiency they are gradually replacing incandescents as the bulb of choice.


Holonyak's parents were Ukrainian immigrants who settled in Southern Illinois; Holonyak's father worked in a coal mine. Holonyak was the first member of his family to receive any type of formal schooling. He once worked 30 straight hours on the Illinois Central Railroad before realizing that a life of hard labor was not what he wanted and he'd prefer to go to school instead. According to Knight Ridder, "The cheap and reliable semiconductor lasers critical to DVD players, bar code readers and scores of other devices owe their existence in some small way to the demanding workload thrust upon Downstate railroad crews decades ago."
Holonyak was John Bardeen's first Ph.D. student at the University of Illinois at Urbana-Champaign. He received his undergraduate, master's, and Ph.D. (1954) from the same university. He created the first visible semiconductor lasers in 1960. In 1963, he again joined Dr. Bardeen, the co-inventor of the transistor, at the University of Illinois and worked on quantum wells and quantum-well lasers.

University of Illinois

As of 2007, he is the John Bardeen Endowed Chair Professor of Electrical and Computer Engineering and Physics at the University of Illinois at Urbana-Champaign[3] and is investigating methods for manufacturing quantum dot lasers. He has been married to his wife Katherine for 51 years. He no longer teaches classes, but he researches full-time. He and Dr. Milton Feng run a transistor laser research center at the University funded by $6.5 million from the United States Department of Defense through DARPA.
10 of his 60 former doctoral students develop new uses for LED technology at Philips Lumileds Lighting Company in Silicon Valley.

Awards and honors

Holonyak has been presented awards by George H.W. Bush, George W. Bush, Emperor Akihito of Japan and Vladimir Putin.
In 1989, Holonyak received the IEEE Edison Medal for 'an outstanding career in the field of electrical engineering with contributions to major advances in the field of semiconductor materials and devices.' Holonyak's former student, Russell Dupuis from the Georgia Institute of Technology, won this same award in 2007.
In 1995, he was awarded the $500,000 Japan Prize for 'Outstanding contributions to research and practical applications of light emitting diodes and lasers.
In 2003, he was awarded the IEEE Medal of Honor.
He has also received the Global Energy International Prize, the National Medal of Technology, the Order of Lincoln Medallion, and the 2004 Lemelson-MIT Prize, also worth $500,000.[4] He has also received the Frederic Ives Medal of the Optical Society of America.
Many colleagues have expressed their belief that he deserves the Nobel Prize for his invention of the LED. On this subject, Holonyak says, "It's ridiculous to think that somebody owes you something. We're lucky to be alive, when it comes down to it."
On 9 November 2007, Holonyak was honored on the University of Illinois campus with a historical marker recognizing his development of the quantum-well laser. It is located on the Bardeen Engineering Quadrangle near where the old Electrical Engineering Research Laboratory used to stand.
In 2008, he was inducted into the National Inventors Hall of Fame (Announced February 14, 2008) (May 2–3, 2008 at Akron, Ohio

Wednesday, April 25, 2012

Build Garden Greenhouse Using LED Lights

The concept of growing plants in your house has been intriguing for excited gardeners for decades. The green house or indoor horticulture thus became a thrilling field of study to many. People grow plants as a hobby and as a great investment, which enables you to reap profits, if nurtured well.

Wholesome plants and flowers are a sight to behold. The green house route of growing plants has to abide to certain specifications for it to reach your goals. Yet the idea is not impossible or far fetched for followers of plants. The right composition of water and nutrition added with correct temperature control are appropriate setting to develop your plants. One another thing, which also is the most important one, is LED lighting inside of the green house.

LED lights are the new style used in green houses. The comparatively cool lights do not dry up the soil and permits the lights to be positioned closer to the plant life. Instead of keeping them very close to the plants all at once, you can actually move them towards the plants slowly. Although LED lights really do not go hot the way other lighting do, you must keep an eye to see the plants stay safe with out any warnings of over heating.

The suitable use of LED lights leads to the growth of safe and colorful plants and herbs. Other features are the capacities of the room; you want to turn in to a green house, extra lights in the room, and the money you invest. However, make sure you collect details from the provider about the lighting layout, before you make an order. It could possibly also enable you to measure the profits you can make, if you plan to make it a small business.

A soil moisture meter must be already in place to measure the moisture content of the soil. It can help to provide correct level of water to the plants. The method to obtain water too should be tested before you fix your LED. The finest temperature needed for plants to grow is around 68F to 86F, which the not so hot LED lights will be able to create.

When the parameters are attained there is nothing to prevent the veteran gardener from manufacturing beautiful vegetables and flowers.

People wonder if the vast recognition of LED lights is hype; a little something which is blown out of proportion! There is a lot of publicity on these lights and their benefits. Wherever we go we face them; they have become an element of our life. So it is only apt that we perform a little analyzing of LE Ds, to know whether the popularity and guarantees associated with them are original or false.

The noticeably more affordable LED lights are harmonious on environment.

The longer life of LE Ds has made it probably the most selected lighting for homes. It stands unparalleled among all other lightings in its sturdiness and low energy application.

LED lights are not huge, which makes them convenient to fit in otherwise tough to fix areas. The bulky nature of regular lighting makes it difficult to fix them in certain points. LEDs are employed to artistically lighten up displays, show cases and other spots which have to be enhanced. LEDs with firmly targeted lights and of a more normally focused nature is available. You could highlight a painting or a beautiful display using the firmly centered LEDs. It is best if you light up your reading table with LED that contains light of much more spread out nature.

Now it is very clear that LEDs certainly are worthy of the popularity they are given!

Wednesday, April 18, 2012

Led Lighting Methods Generating A Brilliant Future Of Light

No one truly knows how quick LEDs are destined to soar or how bright the future of lighting is estimated to be. 1 issue is for positive, although. The popular light bulb might be a issue of your previous, destined to be found only from the ancient museums of every single state. By the seems of your present scenario, the most recent generation of LED lighting techniques might be dazzling ample for making people today sit up and feel agape about the innumerable energy-saving lighting choices which can be produced on the market within their homes, offices and also other business complexes.

LEDs (Light Emitting Diode) are semi-conductor gadgets that convert electrical power immediately into light. They’re much more efficient than conventional light and although three times more highly-priced than their un-dignified counterparts, LEDs are bound to eliminate their highly-priced cost tag using the onset of new technologies. Incandescent or fluorescent lamps is usually purchased at a bargain but is highly-priced on the operational degree. Alternatively, LEDs are 4 times more efficient than fluorescent lighting and lasts 10 times longer too.

Just a couple of many years back, opportunities for LED lighting techniques did not appear an enticing selection for the housing segment, corporations, industries or municipal sectors, owing to the tremendous buying cost. The sad part is, not many realized the expense financial savings after a while positively outweighed the initial costs of these power saving measures.

Due to unprecedented investments in efficient lighting engineering, LED lights are now more inexpensive for homes and corporations As outlined by a recent industry research, the sale of regular light bulbs in numerous European nations dropped by 35 percent from the initially quarter of 2009, with LEDs accounting for 65 percent of your product sales.

Presently LED finds myriad uses in parking locations, street lights, website traffic lights highways, corporate offices, hotels, public buildings, restaurants, gallery, lounge, vehicles and signboards. When regarded as beneficial only for flashlights and laptop personal computers, LED lighting are now revered because the reigning kings and queens from the dwelling lighting arena too.

LEDs supply twice the efficiency of CFLs or Compact Fluorescent light bulbs and also the complete absence of toxic mercury, prolonged lifespan and more quickly turn-on times make LEDs more attractive than other lighting solutions. It’s been estimated from the Department of Energy that by 2025, LEDs possess the potential to reduce national power consumption for lighting by 29 percent, saving $125 billion about the electrical expenses of U.S. households.

Lately, even the vehicle market is generating a roll more than to LED lighting techniques, specifically for indicator lights about the dashboard and rear lights. Technological advancements in LED have come up with high-flux gadgets that make it possible for LEDs to be applied in innumerable lighting applications, specifically those that call for dynamic focusing.

The future of our planet belongs to power efficient lighting and LEDs will play a pivotal part in generating the planet brighter, greener and self-sufficient. It’s only a matter of time along with a small Analysis and Advancement, ahead of the limitations of LEDs are surpassed and people today from all cross-sections of your society deem it essential to adopt LED lighting techniques to light up their lifestyles.

Tuesday, April 3, 2012

LED - Current Trend

In recent years, China\\ s LED industry is developing rapidly, forming a complete LED industrial chain system in support of national policy and downstream applications, driven by demand. The LED industry chain, including upstream of the substrate, epitaxial wafers and chips, package of midstream and downstream of the lighting, display backlighting and other applications. From the industrial chain, LED lighting has gone beyond the backlight LED market, the fastest growing application market. Following a brief introduction to the future development trend of LED lighting:

A luminous efficiency of continuous improvement and product quality is improving steadily

The luminous efficiency is improved steadily by an average of 15% is expected to reach more than 200lm / W, is estimated to reach from 200lm to / W white LED will be the past two or three years available. View, although the 2011 penetration rate of only 6.6% of the overall LED lighting market, but the future growth potential. Countries in the development of LED lighting have introduced policies and preferential measures, of which 2015, Japan plans to LED accounted for the general lighting market will reach 50% and 30% in South Korea, mainland China for 20 percent, up above the 2015 target, this few years will be up to the first phase of work; In addition, LED technology continues to progress, the U.S. DOE set a target point of view, the 2014 white LED components luminous efficiency will reach 200 lm / W, and the price will drop to about $ 2 / klm manufacturers process will exceed the above values.

Second, lower manufacturing costs and sales prices down

The price of the LED will be an average annual rate of 30% or higher rate of decline. By then, the LED lighting into millions of households will fall into place. With the enhancement of the LED chip, LED luminous efficiency is increased, the single LED chip, the cost continues to drop. Upstream investment-driven large-scale production can release lead to strong market competition will drive chip prices fell, which effectively promote the decline in the cost of LED lighting products. Mainstream LED lighting products, cost structure in light beads cost accounting for about 40%, the drive power of 30%, 20% mechanical / thermal material, and the remaining costs about 10%. Seen the cost of lamp beads, the drive power, and mechanical / thermal material costs basically about 90% of the total cost is the main factor affecting the cost of LED lighting products. Further under the price of upstream raw material prices in the future, LED lighting products is expected to accelerate an alternative to the traditional incandescent lamp, energy saving lighting products.

, High voltage LED will become the future is an important direction

High-voltage LEDs (HV LEDs) has two advantages, one effectively reduces the cost and weight of the LED lighting to significantly reduce the cooling system design requirements, which will solve the lighting market, the biggest technical obstacle. VF voltage, current conditions in the IF completely subvert the traditional low-voltage (LV LED) LED VF low voltage, the IF current requirements. LED lighting due to the HV LEDs SOP may reduce the shape of the heating, lighting structure may tend to be more to save cooling materials, greater than 270 degrees light-emitting, low-cost, light weight. And the high-voltage LED chip group of high-voltage, low current, compared with the general low voltage LED low voltage, high current working environment, HVLEDs work fever was significantly reduced; HVLEDs only need high-voltage constant-current source can be a good , the high-voltage constant-current power transformer, electrolytic capacitor to solve the problem of low-voltage LED driver power supply and electrolytic capacitor life.

Fourth, the COB packaging technology has matured

COB packaging have three advantages: low cost, diversification of application convenience and design. COB packaging Bulb currently occupy about 40% of the LED bulb market, Japan and many domestic enterprises have begun to take the COB package mode. Cost and application point of view, the COB has become the mainstream of the future of lighting design. COB packaging of the LED module is installed in the floor pieces of LED chips, the use of many pieces of the chip can not only improve the brightness, and also help to achieve a reasonable configuration of the LED chip, reduce the amount of current of the input of a single LED chip to ensure high efficiency. And this surface light source can greatly expand the package heat dissipation area, so that the heat is more easy to transfer to the shell. Cost lighting applications with traditional COB light source module can save the cost of the device package, the light engine module production costs and the cost of secondary light distribution. Lighting system in the same function, in general can reduce about 30% of the cost of great significance for the promotion of semiconductor lighting applications. In performance, through reasonable to design and mold making microlens, the COB light source module can effectively avoid the discrete light source device combination existence of points of light, glare and other drawbacks also can be through by adding the appropriate red chip combination in does not reduce the light source efficiency and life under the premise of effectively improve the color rendering (now can do 90 or more). In the application, the COB light source module can make installation of the lighting plant production simpler and more convenient. In production, the existing technology and equipment to support large-scale manufacturing of the high yield of COB light source module. With the expansion of the LED lighting market, lighting demand in the rapidly growing, we can according to the needs of different lighting applications, and gradually formed the mainstream product of the series COB light source module, so that large-scale production.

, LED driver power trends

A downstream product development to the interior lighting industry will be gradually broken down. Such as home lighting, hotel lighting, jewelry, lighting, clothing, lighting, advertising lighting, the industry breakdown of the benefits is to make products more fit practical applications, and highlights the advantages of LEDs in various types of lighting.

2.LED lumens of lighting chip technology to improve the product power requirements reduced.

3.LED drive power gradually to the development of modular, intelligent aspects.

Market from the current domestic-oriented, gradually turning into an international-based.

Six, quick start of the indoor lighting market and development

Morphology and function of the current LED indoor lighting products did not jump out of thinking and patterns of traditional lighting products. A single product, is still to replace the incandescent bulb light and alternative LED fluorescent tube lamp-based. LED light source is different from the traditional, has a small size, fast response characteristics, but also the spectral composition of the discontinuous, single light flux is not high. Interior lighting design, LED and conventional light sources should be mutually reinforcing, complementary advantages, rather than substitutes for one another, who leather whose life relationship. Therefore, the LED of the \"intrinsic\" characteristics of quality decided to external \"form, should not be an alternative form of traditional light sources. LED interior lighting will highlight the three major characteristics:

An intelligent lighting control: the use of intelligent control based on environmental changes, the objective requirements of the user pre-demand conditions while automatically collecting all kinds of information in the lighting system, and the collection of information corresponding to the logical analysis, reasoning, judgment and analysis required in the form of storage, display, transmission, the corresponding state feedback control, in order to achieve the desired results. LED control is flexible, fast response, compact, powerful combination of features and intelligent control system to reflect the characteristics of LED.

(2) a variety of functional lighting: lighting environment and engaged in activities closely related to the lighting to meet the needs of people of different visual functions. For example, in the home life, the party need a bright light; to appreciate classical music or light music, soft lighting. Natural light from morning, noon, evening different color temperature on the people\\ s physical, psychological have a great impact.

Building integrated lighting: lighting products and building materials together, making part of the building into part of the lighting. The lighting in the building integration is buried, embedded in the inside of the building to hide the light source or lighting installation, make full use of the surface reflectance or transmittance of the building, showing the building shape, color. This way not only to hide the lighting pipeline or equipment, piping, but also enable the architectural lighting as an integral part of the whole interior design decoration, the effect of a complete and unified interior space.

7, modular is the way to

At present, many types of domestic LED products with different properties, poor interchangeability, which restricted the healthy development of semiconductor lighting industry, LED industry to normalized serialization, standardization development, improve the overall competitiveness of the LED lighting industry, which became LED business first solve the problem. To this end, the semiconductor lighting industry innovation center in Guangdong Province began construction of the project of standard optical components, domestic 100LED enterprises to participate. What is the meaning of the standard optical components of the project: First of all, any industry or industries to seize the standard-setting to seize the commanding heights of industry development can be the dominant industry chain development, reap the maximum benefit of the industrial chain; Second, the standard optical components standard strategy to try will make Guangdong Province Semiconductor will enable Guangdong Province, stand out in the new round of industrial competition in the semiconductor lighting industry, to seize market opportunities, standard with the standard optical components such as national and international standards to promote and expand the lighting companies of market and technical capacity of an unprecedented double. In the next 10 years, to create a number of one hundred billion \"Philips lighting companies to achieve the goal of\" Thirteen five trillion semiconductor lighting industrial scale.

Saturday, February 18, 2012

Importance of Solid-State Lighting - Led & Oled

Starting with 2003, the U.S. Department of Energy has invested with industry partners in research and development of solid-state lighting (SSL)—including both light-emitting diode (LED) and organic light emitting diode (OLED) technologies. Recently there was a competition, called the "L-Prize," where the U.S. government is offering a $10 million prize, to the company that builds the most efficient bulb with the most pleasing light. Why such concentrated attention on SSL?

The answer is simple: because of SSL's rapid ongoing improvements and superior energy-saving potentialPDF. It is estimated that switching to LED lighting over the next two decades could save the country $120 billion in energy costs over that period, reduce the electricity consumption for lighting by one-fourth, and avoid 246 million metric tons of carbon emission.

Improving cost competitiveness. One major roadblock for SSL is cost. Today, the purchase price of LED lighting products is generally higher than that of their conventional counterparts, often by a long shot, and the energy savings often aren't enough to offset the difference within an attractive payback period. So while LEDs are often not cost effective today, there's a wealth of information showing that they will continue to decline rapidly in price.

There's little doubt that solid-state lighting ultimately will emerge as the technology of choice for an unparalleled variety of applications, because, all things being equal, everyone—building owners included—wants to save energy and protect the environment. Meanwhile, all things are not equal, which is why DOE repeatedly emphasizes that SSL is right for some applications but not for others—and why education and due diligence should be key elements in any lighting specification and purchasing process.