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Why Apply for LED Lighting

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Why apply for LED lighting Lighting occupy an important proportion in households energy bills, so it makes up an important part of the electricity you are paying for. Most lighting today is inefficient and is costing you money and emitting vast amounts of CO2 into the atmosphere. LED lights are a great energy efficient alternative and they can save you money and help reduce your impact on the environment. Benefits Of LED Lighting ·LED lights are longer lasting than traditional lighting and downlights, so you don’t have to replace your lights all the time! ·LED lighting uses less power with energy efficient lights which means they are cheaper to run.
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Why apply for LED lighting

Lighting occupy an important proportion in households energy bills, so it makes up an important part of the electricity you are paying for. Most lighting today is inefficient and is costing you money and emitting vast amounts of CO2 into the atmosphere. LED lights are a great energy efficient alternative and they can save you money and help reduce your impact on the environment.

Benefits Of LED Lighting

·LED lights are longer lasting than traditional lighting and downlights, so you don’t have to replace your lights all the time! ·LED lighting uses less power with energy efficient lights which means they are cheaper to run. ·LED lights will help you meet BASIX standards for efficiency in new homes. ·Low heat means LED lights are much safer and will reduce how hard your air conditioner has to work. ·Energy efficient lights create less carbon emissions, so they are better for the environment. ·You don’t have to sacrifice the quality of lights as energy efficient lights bathe the room in a calm

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warmwhite glow. Due to their longer life, you need to purchase less globes/downlights which means less lights are produced and less lights go to landfill.

What is LED Lighting?

LED Lighting are lights which use light emitting diodes (LED’s) which are extremely energy efficient and long lasting. LED lights create less heat than traditional lights, which means they last for longer and it means your air conditioner doesn’t have to work as hard. LED lights are a relatively new technology and can help you save upto 90% on your lighting cost.


1. Question: what is an LED? Answer: a light emitting diode (LED) is a semiconductor device that emits visible light when electrical current passes through it, it is a special kind of diode.

2. Question: what color of light can LED emit?Answer: most LEDs are monochromatic. Light color is associated with the light wavelength. LEDs made with different semiconductor materials emit lights in different wavelengths. LED light wavelengths range from 400 nanometers (blue) to 800 nanometers (red). The colors of popularly available LEDs in the market are red, orange, amber, yellow, green, blue and white.

3. Question: Can LEDs be used to replace conventional incandescent and florescent light bulbs?Answer: yes and no. LEDs have increasingly been used in many different applications to replace old incandescent light bulbs. Examples include LED indicator lights for all kinds of electronic devices such as cell phone, calculators, automotive dash panel, LCD back-lighting, etc., LED seasonal decoration lights for Christmas and holidays, LED traffic signs and other LED direction signs, LED flashing lights, and so on. As currently, LEDs have good brightness, so they can be used to replace incandescent or florescent light bulbs for general lighting purposes.

4. Question: what are the advantages of LEDs compared with conventional incandescent lights?Answer: there are several obvious advantages LEDs have over traditional incandescent light bulbs, they are as follows:-Low power consumption (energy saving)-Long lasting,-Cold lighting,-Ruggedness,-Small size and weight,-Fast switch times,-Simple to use.

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5. Question: could you give more detailed explanations about these LED advantages?Yes. Currently available LEDs are more energy efficient than incandescent bulbs, but less than florescent bulbs with the same light output. The power consumption of popular LEDs ranges from 30mW to 200 mW.People can save money & energy by using LEDs instead of equivalent incandescent decorative bulbs. The rated average working life of LED is 100,000 hours compared with 1,000 hours of incandescent bulbs.LEDs emit cold lights as working LEDs generate very small amount of heat, so LEDs are much safer than equivalent incandescent light bulbs in terms of danger of fire. LEDs don’t have filaments to heat up in order to emit lights just like the case of incandescent bulbs. Lights are emitted from LEDs as a result of energy exchange occurring in the different semiconductor materials an LED is made of. LEDs are usually shielded with solid transparent plastic materials so they are more rugged than incandescent and florescent bulbs that are usually sealed with glass. LEDs can be powered by either AC voltage or DC voltage. The circuit that is required to appropriately drive LEDs is much simpler than that for florescent bulbs.

6. Question: we have seen so many advantages LEDs have over incandescent light and florescent bulbs, are there any disadvantages LEDs exhibit compared with incandescent or florescent bulbs?Yes, the most significant disadvantage is the light output limitation of LED. Currently available LEDs emit limited amount of lights at a relatively angle range, while incandescent and florescent light bulbs illuminate in all directions and give out much more brightness of light.

The second significant disadvantage is the high prices of LEDs. The currently available LEDs in the market are 3 ~ 10 times more expensive than equivalent incandescent light bulbs. This is why some customers still hesitate to buy LED products even though LEDs have so many obvious advantages over incandescent bulbs and people actually can save money by using LED products in the long run.

7. Question: what LED products are currently available for general customers?Answer: the most popular LED products available in volume at the market place are various kinds of LED decoration light products. And in fact, they are ideal for replacing conventional incandescent decoration light products, because when compared with incandescent light products, these LED products save up to 95% energy, have much longer working hours, are more rugged, and safer in terms of danger of fire and electric shock.At present, people can buy beautiful LED light strings, LED rope lights, LED icicle strings, and individual round LED bulbs with changeable colors, LED rope lights, LED pipe lights, and more other LED products will be put into market in the near future.

8. Question: as we notice that in LED light strings, LEDs are in series connection just like incandescent light strings, how do you compare these two kinds of light strings in terms of reliability? Answer: LEDs are more reliable. Most available LED light strings have series configuration like old incandescent light strings, where lights in the string are connected in series with each other, so a disconnection of LED light from the string will always make the entire string fail just like incandescent light strings. However, in the case of light burning, an incandescent light bulb will always burn open,

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namely, the filament of the incandescent bulb breaks, so the whole string will always fail, while an LED light may either burn open like an incandescent light bulb or burn short where a short circuit is formed inside the LED, so the burned LED will stop lighting but all the rest LEDs in the string still light normally. And LEDs usually burn short, therefore, LEDs are more reliable than incandescent light bulbs in that respect.

9. Question: are there any LED strings better than those in series connection?Answer: yes, there is. Various LED string products are more reliable than those LED strings in series connection in market. OUR strings use a unique patented connection configuration that ensures an LED string will work normally even one or several LEDs are disconnected from the string while keeping the low prices and all the features of LED strings.

10. Question: why are LEDs of some colors are more expensive than LEDs of other colors? Answer: the reason is that different semiconductor materials are used for different color LEDs, and some semiconductor materials are more expensive than others; another reason is that manufacturing costs are different. White LEDs are the most expensive because red, green and blue LEDs are combined together to make a white LED.

The Uses of LED Lights

Because LED lights are very efficient in terms of saving energy and cost, they are popular all over the world. LED lighting comes in many different types, shapes and sizes for different purposes.

It is useful and advantageous in many different fields ranging from simple home decorate to architectural design and medical lighting.

There are other types of LEDs as well used as indicators in electronic devices, in flashlights and as car lights. They provide environmental protection

and come in many colors including blue, white, red, yellow and green. Red and yellow LED lights are often used in advertisements and sign displays. LED rope lights and strips are used all over the world for wedding decorations and concerts. These lights also come handy while designing a motion sensing security system for home or office safety and protection against burglars.

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LED traffic control system is also very popular across the globe. Th

ese small lights in different colors are made to operate continuously for directing traffic coming from different directions. Alerts and warning signs are also made by using these types of lights. Flashlights make use of LEDs because of their light weight and extremely powerful nature. They can last for many hours even if required for constant and steady operation. Most of these lights have 2 to 3 miles visibility and are therefore excellent to be used as danger alerts and warnings.

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LED lighting has been found to be superior to incandescent light bulbs and fluorescent tubes in terms of longer and more useful life. These lights also have a faster response time as compared to other types of lights and become fully bright in a matter of microseconds. They can also be used in electronic and electrical experiments where they are required to test passage of electric current through a circuit. They do not contain mercury and are therefore very safe. In fact they can be used to test various circuits where high voltage is expected to be used in order to be safe and avoid electric shock.

LED under car kits are also becoming increasingly popular in today’s fast-moving and modern world. These state-of-the-art lights are used to create an under-car lighting halo which looks beautiful from a distance. Many people who are fond of decorating their cars use these kinds of lights. Their specifications include display of 2.1 million colors, many levels of flash speed, music displays, water proof and shatter proof, and requirement of 12V DC power. It is a multi-functional kit which comes very handy for different purposes. The best thing about this device is that it not expensive at all and lasts for a long time to come.

LED lights can be stored in a compact storage place and come very handy on special occasions like birthday parties, weddings and Christmas celebrations. Another advantage of these small lights is that they are made water proof and can be installed in any area of your choice.

LED lights are also used for entertainment and architectural lighting as part of sophisticated and state-of-the-art interior design. Many people use LED bulbs as portable lights for different purposes.

The uses of led lighting are unlimited. This kind of lighting is not only powerful but also very cost-effective. Because of this reason, many manufacturers are now providing different types of LED lights for almost all kinds of uses. Sheenly Lighting is a professional manufacturer of led lights. You can find many kind of LED lights on the site www.sheenly.com, such as LED tube, LED bulb, LED strips, AND LED panel lights.

LED light is green!

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Time for Green Lights! It is time we go look beyond just jokes about how many people it takes to change a light bulb. Lighting consumes up to 20% of our home energy and up to 30% our work electricity.LED lighting is often overlooked in ‘green building’ literature while more expensive and less satisfactory environmental solutions are pursued. The purpose of this article is to argue that LED lighting should be considered an essential element of any ‘green’ building, house, or construction project. Let’s start with some of the benefits of LEDs:

LED lighting uses 80% less energy than incandescent lighting.LED lighting produces 500% more light per Watt.LED lights have lenses that focus the light into a pattern of equal distribution adding to energy savings as light is not wasted bouncing in unneeded directions.LED lights do not produce as much heat. This can save on energy and maintenance costs.LED lights do not emit significant UV or IR radiation. IR is back to the heat issue, and UV is something we generally try to avoid.LED lights last 50,000 hours or about 25 times longer than incandescent lights. This saves obviously on maintenance and disposal.LED lights do not contain mercury common in fluorescents.

The Department of Energy estimates that LED lighting could reduce U.S. energy consumption by 29% by 2025。Recent university research and other advancements have help LEDs to replace incandescent light bulbs in the next five to seven years.

Light-emitting diodes (LEDs) are not a new technology (1970s). LEDs offer benefits such as small size, long lamp life, low heat output, energy savings and durability. They also allow extraordinary design flexibility in color changing, dimming and distribution by combining these small units into desired shapes, colors, sizes and lumen packages. LEDs have advanced from use as indicator lights and in numeric displays to a range of innovative and new applications, including accent lights, task lights, traffic lights, signage, outdoor lighting and down-lighting.

If there was an apparent drawback, at least from the consumer perspective, it would be the expense. An led par38 12 watt light can cost 10 times as much an incandescent light. In fact, however, the expense of LEDs is not a drawback at all. Once, energy and replacement costs are figured in the LED lights actually

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save money. Simply consider the cost of 24 extra replacements of the incandescent light. Then factor the extra energy use and its really not even close. We did not include that in the summer LEDs put less load on the air conditioning. Its clear the LED light ultimately saves money, but many are reluctant to purchase due to the longer term of the payback. Over the last few years there has been advancements increasing the light output per chip. Once you get more light out of the chip, then the cost goes down in terms of how much light it produces.

Finally, the real benefit of LEDs is that they are cool. Yes, they are not as hot as incandescent lights, but I mean they are cool. When you see the lights and what they do it is impressive. Everything from PAR lights to recessed ceiling lights are available all at costs that payback before too long. You should also consider the source of your LEDs.ctledlights.com is a professional manufacturer of LED lights.

Current Developments of LED

To overcome these difficult issues new technology was needed. LED designers turned to laser diode technology for solutions. In parallel with the rapid developments in LED technology, laser diode technology had also been making progress. In the late 1980’s laser diodes with output in the visible spectrum began to be commercially produced for applications such as bar bode readers, measurement and alignment systems and next generation storage systems. LED designers looked to using similar techniques to produce high brightness and high reliability LEDs. This led to the development of InGaAlP (Indium Gallium Aluminum Phosphide) visible LEDs. The use of InGaAlP as the luminescent material allowed flexibility in the design of LED output color simply by adjusting the size of the energy band gap. Thus, green, yellow, orange and red LEDs all could be produced using the same basic technology. Additionally, light output degradation of InGaAlP material is significantly improved even at elevated temperature and humidity.

As a result of these developments, much of the growth for LEDs in the 1990’s was concentrated in three main areas: The first was in traffic control devices such as stop lights, pedestrian signals, barricade lights and road hazard signs. The second was in variable message signs such as the one located in Times Square New York which displays commodities, news and other information. The third concentration was in automotive applications.

The visible LED has come a long way since its introduction more than 30 years ago and has yet to show any signs of slowing down. Blue LEDs, which were introduced in the early to mid 1990’s, have become the cornerstone to an entire generation of new applications. Blue LEDs because of their high photon energies (>2.5eV) and relatively low eye sensitivity (465nm typical wavelength) have always been difficult to manufacture. In addition the technology necessary to fabricate these LEDs is very different and far less advanced than standard LED materials. The blue LEDs available today consist of GaN (gallium nitride) and SiC (silicon carbide) construction with brightness levels in excess of 10000mcd @ 20mA. Since blue is one of the primary colors, (the other two being red and green), full color solid state LED signs, TV’s etc. are becoming commercially available. The first decade of the 21st century will see a large growth in RGB (full color) LED applications. Other applications for blue LEDs include medical diagnostic equipment and photolithography.

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It is also possible to produce other colors using the same basic GaN technology and growth processes. For example, a high brightness green (approximately 500nm – 530nm) LED has been developed that is currently being used as a replacement to the green bulb in traffic lights. Other colors including purple are also possible. With the introduction of blue LEDs, it became possible to produce white light probably the most exciting new development in LED technology to date. White light is currently made in one of 2 ways. The first is by selectively combining the proper combination of red, green and blue light. This process however, requires sophisticated software and hardware design to implement. In addition, the brightness level is low and the overall light output of each RGB die being used degrades at a different rate resulting in an eventual color unbalance. The 2nd and most dominant method of achieving white light output is to use a phosphor coating (typically - Yttrium Aluminum Garnet or YAG) on the surface of a blue LED. The blue die excites the phosphor causing it to glow white.

In summary, LED’s have gone from infancy to adolescence and are experiencing some of the most rapid market growth of their lifetime. By using InGaAlP material with MOCVD as the growth process, combined with efficient delivery of generated light and efficient use of injected current, some of the brightest, most efficient and most reliable LEDs are now available. This technology together with other novel LED structures will ensure wide application of LEDs. Further developments on white light output will also guarantee the continued increase in applications of these economical light sources and may eventually replace standard incandescent and fluorescent lighting.

The History of LED Technology

A light emitting diode (LED) is essentially a PN junction semiconductor diode that emits a monochromatic (single color) light when operated in a forward biased direction. The basic structure of an LED consists of the die or light emitting semiconductor material, a lead frame where the die is actually placed, and the encapsulation epoxy which surrounds and protects the die (Figure below shows both standard lamp type and surface mount type).

The first commercially usable LEDs were developed in the 1960’s by combining three primary elements: gallium, arsenic and phosphorus (GaAsP) to obtain a 655nm red light source. Although the luminous intensity was very low with brightness levels of approximately 1-10mcd @ 20mA, they still found use in a variety of applications, primarily as indicators. Following GaAsP, GaP, or gallium phosphide, red LEDs were developed. These devices were found to exhibit very high quantum efficiencies, however, they played only a minor role in the growth of new applications for LEDs.

This was due to two reasons: First, the 700nm wavelength emission is in a spectral region where the sensitivity level of the human eye is very low (Figure 2) and therefore, it does not "appear" to be very bright even though the efficiency is high (the human eye is most responsive to yellow-green light). Second, this high efficiency is only achieved at low currents. As the current increases, the efficiency decreases. This proves to be a disadvantage to users such as outdoor message sign manufacturers who typically multiplex their LEDs at high currents to achieve brightness levels similar to that of DC

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continuous operation. As a result, GaP red LEDs are currently used in only a limited number of applications.

As LED technology progressed through the 1970’s, additional colors and wavelengths became available. The most common materials were GaP green and red, GaAsP orange or high efficiency red and GaAsP yellow, all of which are still used today (Table3). The trend towards more practical applications was also beginning to develop. LEDs were found in such products as calculators, digital watches and test equipment. Although the reliability of LEDs has always been superior to that of incandescent, neon etc., the failure rate of early devices was much higher than current technology now achieves. This was due in part to the actual component assembly that was primarily manual in nature. Individual operators performed such tasks as dispensing epoxy, placing the die into position, and mixing epoxy all by hand. This resulted in defects such as "epoxy slop" which caused VF (forward voltage) and VR (reverse voltage) leakage or even shorting of the PN junction. In addition, the growth methods and materials used were not as refined as they are today. High numbers of defects in the crystal, substrate and epitaxial layers resulted in reduced efficiency and shorter device lifetimes.

It wasn’t until the 1980’s when a new material, GaAlAs (gallium aluminum arsenide) was developed, that a rapid growth in the use of LEDs began to occur. GaAlAs technology provided superior performance over previously available LEDs. The brightness was over 10 times greater than standard LEDs due to increased efficiency and multi-layer, heterojunction type structures. The voltage required for operation was lower resulting in a total power savings. The LEDs could also be easily pulsed or multiplexed. This allowed their use in variable message and outdoor signs. LEDs were also designed into such applications as bar code scanners, fiber optic data transmission systems, and medical equipment. Although this was a major breakthrough in LED technology, there were still significant drawbacks to GaAlAs material. First, it was only available in a red 660nm wavelength. Second, the light output degradation of GaAlAs is greater than that of standard technology. It has long been a misconception with LEDs that light output will decrease by 50% after 100,000 hours of operation. In fact, some GaAlAs LEDs may decrease by 50% after only 50,000 -70,000 hours of operation. This is especially true in high temperature and/or high humidity environments. Also during this time, yellow, green and orange saw only a minor improvement in brightness and efficiency which was primarily due to improvements in crystal growth and optics design. The basic structure of the material remained relatively unchanged.

All About Energy

In just a few years, solid-state lighting has breached barriers of performance and cost effectiveness established by conventional technologies at the end of their evolutionary cycles. While fluorescent, incandescent (including halogen), and high intensity discharge sources are certain to improve, the improvements will be incremental.

LEDs, on the other hand, have already eclipsed incandescent sources, and when fixture performance is considered, are powering past compact fluorescent in real world applications today. With their long service life, compact size, and far greater directional control (meaning high application efficiencies), LED

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technology produces a unique opportunity to re-think many of the old paradigms of lighting system design. As the performance of LEDs continues its rapid expansion, and the cost of light delivered continues to drop, the obvious choice in general illumination will inevitably point toward solid-state illumination.

Not only does energy savings from solid-state lighting not come with the liability of mercury that fluorescent lamps require, reduction in energy use overall means a reduction in greenhouse gas emissions, reduced mercury and phosphor emissions from coal burning, a slower depletion of fossil fuel sources, reduced contribution to land fills from coal cinder, and a lower demand to pursue nuclear and other hazardous sources of energy.

LED lighting saves money on long run

Canadians use more energy per capita than any other nation in the world. It’s expensive, both in cost to the environment and to your family’s budget, and we need to find ways to cut back our usage.

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We’ve been making the switch to compact fluorescents (CFLs) from incandescent bulbs to save energy, but many people aren’t happy with CFLs. They cost more than standard bulbs and they contain mercury — which is an environmental concern. They take time to warm up to full brightness, especially in cold weather. They flicker and buzz and many people feel they produce an unappealing quality of light — it’s a fluorescent, after all.

Another option to consider when planning your lighting is LEDs. Light Emitting Diode (LED) technology uses a fraction of energy compared to conventional incandescent or even CFLs. And they last a long time before needing replacement — up to 50,000 hours, compared to 6,000 for a CFL or 1,000 for standard incandescent bulbs.

Incandescent lights work by using electricity to heat a filament until it glows. They also give off a lot of excess heat — you know that if you’ve ever touched a light bulb after it’s been on for even a short while. Fluorescent lights work by passing electrical current through a gas-filled tube, which causes it to emit light. LEDs work by channelling electric current through a semi-conductor material — 100 per cent of which is turned into light, with no waste heat produced. LEDs are very energy efficient.

So apparently, LED lighting is the best choice for money saving and environment protection.

What is Color Temperature

Color temperature

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The CIE 1931 x,y chromaticity space, also showing the chromaticities of black-body light sources of various temperatures (Planckian locus), and lines of constant correlated color temperature.

Color temperature is a characteristic of visible light that has important applications in lighting, photography, videography, publishing, manufacturing, astrophysics, and other fields. The color temperature of a light source is the temperature of an ideal black-body radiator that radiates light of comparable hue to that light source. The temperature is conventionally stated in units of absolute temperature, kelvin (K). Color temperature is related to Planck's law and to Wien's displacement law.

Higher color temperatures (5,000 K or more) are called cool colors (blueish white); lower color temperatures (2,700–3,000 K) are called warm colors (yellowish white through red).[1]



1 Categorizing different lighting

o 1.1 The Sun

2 Color temperature applications

o 2.1 Film photography

o 2.2 Desktop publishing

o 2.3 TV, video, and digital still cameras

o 2.4 Artistic application via control of color temperature

o 2.5 Lighting

3 Correlated color temperature

o 3.1 Motivation

o 3.2 Background

o 3.3 Calculation

3.3.1 Robertson's method

o 3.4 Precautions

o 3.5 Approximation

4 Color rendering index

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5 Spectral power distribution

6 See also

7 References

8 Further reading

9 External links

Categorizing different lighting

Because it is the standard against which other light sources are compared, the color temperature of the thermal radiation from an ideal black body radiator is defined as equal to its surface temperature in kelvins, or alternatively in mired (micro-reciprocal degrees Kelvin).[2]

To the extent that a hot surface emits thermal radiation but is not an ideal black-body radiator, the color temperature of the light is not the actual temperature of the surface. An incandescent light bulb's light is thermal radiation and the bulb is very close to an ideal black-body radiator, so its color temperature is essentially the temperature of the filament.

Many other light sources, such as fluorescent lamps, emit light primarily by processes other than thermal radiation. This means the emitted radiation does not follow the form of a black-body spectrum. These sources are assigned what is known as a correlated color temperature (CCT). CCT is the color temperature of a black body radiator which to human color perception most closely matches the light from the lamp. Because such an approximation is not required for incandescent light, the CCT for an incandescent light is simply its unadjusted temperature, derived from the comparison to a black body radiator.

The Sun

As the sun crosses the sky, it may appear to be red, orange, yellow or white depending on its position. The changing color of the sun over the course of the day is mainly a result of scattering of light, and is unrelated to black body radiation. The blue color of the sky is caused by Rayleigh scattering of the sunlight from the atmosphere, which tends to scatter blue light more than red.

Daylight has a spectrum similar to that of a black body, with a correlated color temperature of 6500K.

Temperature Source

1,700 K Match flame

1,850 K Candle flame

2,700–3,300 K Incandescent light bulb

3,350 K Studio "CP" light

3,400 K Studio lamps, photofloods, etc.

4,100 K Moonlight, xenon arc lamp

5,000 K Horizon daylight

5,500–6,000 K Typical daylight, electronic flash

6,500 K Daylight, overcast

9,300 K CRT screen

Note: These temperatures are merely characteristic;considerable variation may be present.

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Hues of the Planckian locus, in the mired scale.

For colors based on the black body, blue occurs at higher temperatures, while red occurs at lower, cooler, temperatures. This is the opposite of the cultural associations that colors have taken on, with "red" as "hot", and "blue" as "cold". The traditional associations come from a variety of sources, such as water and ice appearing blue, while heated metal and fire are of a reddish hue. However, the redness of these heat sources comes precisely from the fact that red is the coolest of the visible colors, the first color emitted as heat increases.

Color temperature applications

In digital photography, color temperature is sometimes used interchangeably with white balance, which allow a remapping of color values to simulate variations in ambient color temperature. Most digital cameras and RAW image software provide presets simulating specific ambient values (e.g., sunny, cloudy, tungsten, etc.) while others allow explicit entry of white balance values in Kelvin. These settings vary color values along the blue–yellow axis, while some software includes additional controls (sometimes labeled tint) adding the magenta–green axis.

Film photography

Film sometimes appears to exaggerate the color of the light, since it does not adapt to lighting color as our visual perception does. An object that appears to the eye to be white may turn out to look very blue or orange in a photograph. The color balance may need to be corrected while shooting or while printing to achieve a neutral color print.

Film is made for specific light sources (most commonly daylight film and tungsten film), and used properly, will create a neutral color print. Matching the sensitivity of the film to the color temperature of the light source is one way to balance color. If tungsten film is used indoors with incandescent lamps, the yellowish-orange light of the tungsten incandescent bulbs will appear as white (3,200 K) in the photograph.

Filters on a camera lens, or color gels over the light source(s) may also be used to correct color balance. When shooting with a bluish light (high color temperature) source such as on an overcast day, in the shade, in window light or if using tungsten film with white or blue light, a yellowish-orange filter will correct this. For shooting with daylight film (calibrated to 5,600 K) under warmer (low color temperature) light sources such as sunsets, candle light or tungsten lighting, a bluish (e.g., #80A) filter may be used.

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If there is more than one light source with varied color temperatures, one way to balance the color is to use daylight film and place color-correcting gel filters over each light source.

Photographers sometimes use color temperature meters. Color temperature meters are usually designed to read only two regions along the visible spectrum (red and blue); more expensive ones read three regions (red, green, and blue). However, they are ineffective with sources such as fluorescent or discharge lamps, whose light varies in color and may be harder to correct for. Because it is often greenish, a magenta filter may correct it. More sophisticated colorimetry tools can be used where such meters are lacking.

Desktop publishing

In the desktop publishing industry, it is important to know a monitor’s color temperature. Color matching software, such as ColorSync will measure a monitor's color temperature and then adjust its settings accordingly. This enables on-screen color to more closely match printed color. Common monitor color temperatures, along with matching standard illuminants in parentheses, are as follows:

5,000 K (D50)

5,500 K (D55)

6,500 K (D65)

7,500 K (D75)

9,300 K.

Note: D50 is scientific shorthand for a Standard illuminant: the daylight spectrum at a correlated color temperature of 5,000 K. (Similar definition for D55, D65 and D75.) Designations such as D50 are used to help classify color temperatures of light tables and viewing booths. When viewing a color slide at a light table, it is important that the light be balanced properly so that the colors are not shifted towards the red or blue.

Digital cameras, web graphics, DVDs, etc. are normally designed for a 6,500 K color temperature. The sRGB standard commonly used for images on the internet stipulates (among other things) a 6,500 K display whitepoint.

TV, video, and digital still cameras

The NTSC and PAL TV norms call for a compliant TV screen to display an electrically black and white signal (minimal color saturation) at a color temperature of 6,500 K. On many consumer-grade televisions, there is a very noticeable deviation from this requirement. However, higher-end consumer-grade televisions can have their color temperatures adjusted to 6,500 K by using a preprogrammed setting or a custom calibration. Current versions of ATSC explicitly call for the color temperature data to be included in the data stream, but old versions of ATSC allowed this data to be omitted. In this case,

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current versions of ATSC cite default colorimetry standards depending on the format. Both of the cited standards specify a 6,500 K color temperature.

Most video and digital still cameras can adjust for color temperature by zooming into a white or neutral colored object and setting the manual "white balance" (telling the camera that "this object is white"); the camera then shows true white as white and adjusts all the other colors accordingly. White-balancing is necessary especially when indoors under fluorescent lighting and when moving the camera from one lighting situation to another. Most cameras also have an automatic white balance function that attempts to determine the color of the light and correct accordingly. While these settings were once unreliable, they are much improved in today's digital cameras, and will produce an accurate white balance in a wide variety of lighting situations.

Artistic application via control of color temperature

The house above appears a light cream during the midday, but seems a bluish white here in the dim light before full sunrise. Note the different color temperature of the sunrise in the background.

Experimentation with color temperature is obvious in many Stanley Kubrick films; for instance in Eyes Wide Shut the light coming in from a window was almost always conspicuously blue, whereas the light from lamps on end tables was fairly orange. Indoor lights typically give off a yellow hue; fluorescent and natural lighting tends to be more blue.

Video camera operators can white-balance objects which aren't white, downplaying the color of the object used for white-balancing. For instance, they can bring more warmth into a picture by white-balancing off something light blue, such as faded blue denim; in this way white-balancing can serve in place of a filter or lighting gel when those aren't available.

Cinematographers do not "white balance" in the same way as video camera operators; they can use techniques such as filters, choice of film stock, pre-flashing, and after shooting, color grading (both by exposure at the labs and also digitally). Cinematographers also work closely with set designers and lighting crews to achieve the desired effects.

For artists, most pigments and papers have a cool or warm cast, as the human eye can detect even a minute amount of saturation. Gray mixed with yellow, orange or red is a "warm gray". Green, blue, or purple, create "cool grays". Note that this sense of temperature is the reverse of that of real

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temperature; bluer is described as "cooler" even though it corresponds to a higher-temperature blackbody.

Warm grey Cool grey

Mixed with 6% yellow. Mixed with 6% blue.

Lighting designers sometimes select filters by color temperature, commonly to match light that is theoretically white. Since fixtures using discharge type lamps produce a light of considerably higher color temperature than tungsten lamps, using the two in conjunction could potentially produce a stark contrast, so sometimes fixtures with HID lamps, commonly producing light of 6,000–7,000 K, are fitted with 3,200 K filters to emulate tungsten light. Fixtures with color mixing features or with multiple colors, (if including 3,200 K) are also capable of producing tungsten like light. Color temperature may also be a factor when selecting lamps, since each is likely to have a different color temperature.[3]


Color Temperature comparison of common electric lamps.

For lighting building interiors, it is often important to take into account the color temperature of the lights used. For example, a warmer (i.e., lower color temperature) light is often used in public areas to promote relaxation, while a cooler (higher color temperature) light is used to enhance concentration in offices.[4]

Correlated color temperature

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The correlated color temperature (Tcp) is the temperature of the Planckian radiator whose perceived colour most closely resembles that of a given stimulus at the same brightness and under specified viewing conditions

— CIE/IEC 17.4:1987, International Lighting Vocabulary (ISBN 3900734070)[5]


Black body radiators are the reference by which the whiteness of light sources is judged. A black body can be described by its color temperature, whose hues are depicted above. By analogy, nearly-Planckian light sources such as certain fluorescent or high-intensity discharge lamps can be judged by their correlated color temperature (CCT); the color temperature of the Planckian radiator that best approximates them. The question is: what is the relationship between the light source's relative spectral power distribution and its correlated color temperature?


Judd's (r,g) diagram. The concentric curves indicate the loci of constant purity.

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Judd's Maxwell triangle. Planckian locus in red. Translating from trilinear co-ordinates into Cartesian co-ordinates leads to the next diagram.

Judd's uniform chromaticity space (UCS), with the Planckian locus and the isotherms from 1,000 K to 10,000 K, perpendicular to the locus. Judd calculated the isotherms in this space before translating them back into the (x,y) chromaticity space, as depicted in the diagram at the top of the article.

Close up of the Planckian locus in the CIE 1960 UCS, with the isotherms in mireds. Note the even spacing of the isotherms when using the reciprocal temperature scale, and compare with the similar figure below. The even spacing of the isotherms on the locus implies that the mired scale is a better measure of perceptual color difference than the temperature scale.

The notion of using Planckian radiators as a yardstick against which to judge other light sources is not a new one.[6] In 1923, writing about "grading of illuminants with reference to quality of color…the temperature of the source as an index of the quality of color", Priest essentially described CCT as we understand it today, going so far as to use the term apparent color temperature, and astutely recognized three cases:[7]

"Those for which the spectral distribution of energy is identical with that given by the Planckian formula."

"Those for which the spectral distribution of energy is not identical with that given by the Planckian formula, but still is of such a form that the quality of the color evoked is the same as would be evoked by the energy from a Planckian radiator at the given color temperature."

"Those for which the spectral distribution of energy is such that the color can be matched only approximately by a stimulus of the Planckian form of spectral distribution."

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Several important developments occurred in 1931. In chronological order:

1. Davis published a paper on correlated color temperature (his term). Referring to the Planckian locus on the r-g diagram, he defined the CCT as the average of the primary component temperatures (RGB CCTs), using trilinear coordinates.[8]

2. The CIE announced the XYZ color space.

3. Judd published a paper on the nature of "least perceptible differences" with respect to chromatic stimuli. By empirical means he determined that the difference in sensation, which he termed ΔE for a "discriminatory step between colors…Empfindung" (German for sensation) was proportional to the distance of the colors on the chromaticity diagram. Referring to the (r,g) chromaticity diagram depicted aside, he hypothesized that:[9]

KΔE = |c1 - c2| = max(|r1 - r2|, |g1 - g2|)

These developments paved the way for the development of new chromaticity spaces that are more suited to the estimation of correlated color temperatures and chromaticity differences. Bridging the concepts of color difference and color temperature, Priest made the observation that the eye is sensitive to constant differences in reciprocal temperature:[10]

A difference of one micro-reciprocal-degree (μrd) is fairly representative of the doubtfully perceptible difference under the most favorable conditions of observation.

Priest proposed to use "the scale of temperature as a scale for arranging the chromaticities of the several illuminants in a serial order." Over the next few years, Judd published three more significant papers:

1. The first verified the findings of Priest,[7] Davis,[8] and Judd,[9] with a paper on sensitivity to change in color temperature.[11]

2. The second proposed a new chromaticity space, guided by a principle that has become the holy grail of color spaces: perceptual uniformity (chromaticity distance should be commensurate with perceptual difference). By means of a projective transformation, Judd found a more uniform chromaticity space (UCS) in which to find the CCT. Judd determined the nearest color temperature by simply finding the nearest point on the Planckian locus to the chromaticity of the stimulus on Maxwell's color triangle, depicted aside. The transformation matrix he used to convert X,Y,Z tristimulus values to R,G,B coordinates was:[12]


From this one can find these chromaticities:[13]

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3. The third depicted the locus of the isothermal chromaticities on the CIE 1931 x,y chromaticity diagram.[14] Since the isothermal points formed normals on his UCS diagram, transformation back into the xy plane revealed them still to be lines, but no longer perpendicular to the locus.

MacAdam's "uniform chromaticity scale" diagram; a simplification of Judd's UCS.


Judd's idea of determining the nearest point to the Planckian locus on a uniform chromaticity space is current. In 1937, MacAdam suggested a "modified uniform chromaticity scale diagram", based on certain simplifying geometrical considerations:[15]

This (u,v) chromaticity space became the CIE 1960 color space, which is still used to calculate the CCT (even though MacAdam did not devise it with this purpose in mind). [16] Using other chromaticity spaces, such as u'v', leads to non-standard results that may nevertheless be perceptually meaningful. [17]

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Close up of the CIE 1960 UCS. The isotherms are perpendicular to the Planckian locus, and are drawn to indicate the maximum distance from the locus that the CIE considers the correlated color temperature to be meaningful:

The distance from the locus (i.e., degree of departure from a black body) is traditionally indicated in units of ; positive for points above the locus. This concept of distance has evolved to become Delta E, which continues to be used today.

Robertson's method

Before the advent of powerful, personal computers, it was common to estimate the correlated color temperature by way of interpolation from look-up tables and charts. [18] The most famous such method is Robertson's,[19] who took advantage of the relatively even spacing of the mired scale (see above) to calculate the CCT Tc using linear interpolation of the isotherm's mired values:[20]

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Computation of the CCT Tc corresponding to the chromaticity coordinate in the CIE 1960 UCS.

where and are the color temperatures of the look-up isotherms and i is chosen such that . (Furthermore, the test chromaticity lies between the only two adjacent lines for which


If the isotherms are tight enough, one can assume , leading to

The distance of the test point to the i'th isotherm is given by

where is the chromaticity coordinate of the i'th isotherm on the Planckian locus and m i is the isotherm's slope. Since it is perpendicular to the locus, it follows that where li is the slope of the locus at .


Although the CCT can be calculated for any chromaticity coordinate, the result is meaningful only if the light sources are nearly white.[21] The CIE recommends that "The concept of correlated color temperature should not be used if the chromaticity of the test source differs more than [ ] from the Planckian radiator."[22] Beyond a certain value of , a chromaticity co-ordinate may be equidistant to two points on the locus, causing ambiguity in the CCT.


If a narrow range of color temperatures is considered—those encapsulating daylight being the most practical case—one can approximate the Planckian locus in order to calculate the CCT in terms of chromaticity coordinates. Following Kelly's observation that the isotherms intersect in the purple region near (x=0.325, y=0.154),[18] McCamy proposed this cubic approximation:[23]

CCT(x, y) = -449n3 + 3525n2 - 6823.3n + 5520.33

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where n = (x - xe)/(y - ye) is the inverse slope line and (xe = 0.3320, ye = 0.1858) is the "epicenter"; quite close to the intersection point mentioned by Kelly. The maximum absolute error for color temperatures ranging from 2856 (illuminant A) to 6504 (D65) is under 2 K.

A more recent proposal, using exponential terms, considerably extends the applicable range by adding a second epicenter for high color temperatures:[24]

CCT(x,y) = A0 + A1exp(-n/t1) + A2exp(-n/t2) + A3exp(-n/t3)

where n is as before and the other constants are defined below:

3–50 kK 50–800 kK

xe 0.3366 0.3356

ye 0.1735 0.1691

A0 -949.86315 36284.48953

A1 6253.80338 0.00228

t1 0.92159 0.07861

A2 28.70599 5.4535×10-36

t2 0.20039 0.01543

A3 0.00004

t3 0.07125

Color rendering index

The CIE color rendering index (CRI) is a method to determine how well a light source's illumination of eight sample patches compares to the illumination provided by a reference source. Cited together, the CRI and CCT give a numerical estimate of what reference (ideal) light source best approximates a particular artificial light, and what the difference is.

Spectral power distribution

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Here is an example of how different an incandescent lamp's SPD graph is from that of a fluorescent lamp.

Light sources and illuminants may be characterized by their spectral power distribution (SPD). The relative SPD curves provided by many manufacturers may have been produced using 10-nanometre (nm) increments or more on their spectroradiometer.[25] The result is what would seem to be a smoother ("fuller spectrum") power distribution than the lamp actually has. Owing to their spiky distribution, much finer increments are advisable for taking measurements of fluorescent lights, and this requires more expensive equipment.


1. ̂ http://www.handprint.com/HP/WCL/color12.html

2. ̂ Wallace Roberts Stevens (1951). Principles of Lighting. Constable. http://books.google.com/?id=gH5RAAAAMAAJ&q=micro-reciprocal-degree+date:0-1960&dq=micro-reciprocal-degree+date:0-1960.

3. ̂ Color Temperature and Metal Halide Sources

4. ̂ Rüdiger Paschotta (2008). Encyclopedia of Laser Physics and Technology. Wiley-VCH. p. 219. ISBN 9783527408283. http://books.google.com/

The Benefit of Energy Efficiency

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High power white LED serves as the fourth generation electricity light source and LED has already been the hottest green light source in illumination market. High power white LED will entirely replace traditional incandescent lamp, halogen lamp, and fluorescent lamp in the near future. LED will be eventually turning out to be the new light source of environment protection in 21 century.

Typically, the traditional incandescent lamp carries out “high temperature “directly into fuse and then spreading out the light afterward that this means normally causes 90% of power diffusing with hot radiation. Simply put, it will not only waste energy, but also will make the indoor and outdoor temperature increasing. Consequently, the power consumption will be increasing a lot more than before due to dwellers use air condition facilities profusely. To a certain degree, the global warming is boosted up progressively on earth.

The white LED merely consumes the power consumption in 10~20% same as incandescent lamp. As well LED and incandescent lamp have the same brightness. The incandescent lamp can use for 1000 hours only, and white light the LED light can utilize for more than 20000 hours.

White LED serves as light source which will have its own potentially enormous marketing and the prospect of application

Nation/area Condition Economic benefit Environment benefit


Replace 55% incandescent lamps and 55% fluorescent lamps

Save USD 35,000,000,000 electricity charges yearly

Reduce 7.55 billion tons carbon dioxide emissions every year

JapanReplace 100% incandescent lamps

Save 1 to 2 nuclear power stations

Save 100 million liters of crude oils to consume every year


Replace 25% incandescent lamps and 100% fluorescent lamps

Save 110 billion degrees electricity, which is about the same as nuclear power station to generate electricity quantity

Save much CO2 emission

High power white LED serves as illuminate light source have a great deal of benefits to utilize due to small size, economic power consumption, low temperature, long life span, react quickly, safe and low electric voltage, great weather resistance, directive lighting control, and so forth. These benefits are widely applied in the

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petroleum, chemical engineering, Mineral Mountain, railroad, troops, car, city, video screen and stadium building. (sheenly.com)

10 main reasons for LED to replace incandescent lamps

1. Energy efficient

Recently introduced ultrahigh brightness LEDs are much more energy efficient than incandescent lights. The efficacy of a typical residential application LED is approximately 50-120 lumens per watt (LPW), whereas incandescent bulbs have an efficacy of about 12-24 LPW and fluorescent lamp of about 50-70 LPW. Also LED light-focusing character and corn beam are better.


2. Saves electricity

LED lighting power consumption 0.03-0.06 watt, it uses direct current actuation. The lighting actuation’s voltage is 1.5-3.5volts, the electric current is 15-18 millimeter ampere, and reflection is quick, may in high frequency operate, uses in the similar illuminating effect situation, the power consumption is 1/10000 of incandescent lamp, or 1/2 of fluorescent tube, similar effect daylight lamp more than 40 watt, but uses LED each power only 8 watt.


3. Long Life

LEDs life are 100,000 hours and LED lamps can be use 5-10 years, compared to 1,000-2,000 hours for incandescent bulbs. This reduces maintenance costs and time. And LEDs are solid state devices which have no filaments or glass tubes to break. Also LEDs don't suddenly burn out like tungsten sources, but slowly fade over time, allowing planned maintenance.


4. Low Voltage

LEDs can be operated by low volts.


5. No mercury

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NO mercury. LED is absolutely environmental friendly.


6. Safe

LED is low temperature, non heat radiant, can be safety to touch. The form of lighting, the angle, the color temperature of lighting can be control. Also LED hasn’t dizzy light and non UV emissions.


7. Environmentally friendly breakable

LED been call “green light source”, because it is solid Light-Emitting Diode, can be pounded and it is not easy to break, is recyclable, lowest pollution, reduces much noxious fumes as Greenhouse Gas as Sulfur dioxide, category, and Carbon dioxide...ext.


8. Light instantly

LED have no warming-up time, unlike compact fluorescent bulbs, which can take several seconds to reach full brightness.


9. Money saving

Although LED light bulbs are more expensive to buy than incandescent bulbs, however they are much cheaper to run and last much longer than incandescent lights, they save money in the long run.


10. Small size

LED can be creating very small, can easily to suit in a specific designs or available power supplies.

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MacAdam ellipse

In the study of color vision, MacAdam ellipses refer to the region on a chromaticity diagram which contains all colors which are indistinguishable, to the average human eye, from the color at the center of the ellipse. The contour of the ellipse therefore represents the just noticeable differences of chromaticity.

MacAdam ellipses for one of MacAdam's test participants, Perley G. Nutting Jr. (observer "PGN"), plotted on the CIE 1931 xy chromaticity diagram. The ellipses are ten times their actual size, as depicted in MacAdam's paper.


1 History

2 Procedure

3 Extension to three dimensions

4 Effects in color theory

5 See also

6 References

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In the study of color perception, the first question that usually comes to mind is "what color is it?". In other words, we wish to develop a method of specifying a particular color which allows us to differentiate it from all other colors. It has been found that three quantities are needed to specify a particular color. For example, the relative amounts of red, green and blue in a color will serve to specify that color completely. This question was first approached by a number of researchers in the 1930's and their results were formalized in the specification of the CIE XYZ color space.

The second question we might ask, given two colors, is "how different are these two colors?" Just as the first question was answered by developing a color space in which three numbers specified a particular color, we are now asking effectively, how far apart these two colors are. This particular question was considered by researchers dating back to Helmholtz and Schrödinger,[1] and later in industrial applications,[2] however experiments by Wright and Pitt,[3] and David MacAdam provided much-needed empirical support.[4]


MacAdam set up an experiment in which a trained observer viewed two different colors, at a fixed luminance of about 48 cd/m2. One of the colors (the "test" color) was fixed, but the other was adjustable by the observer, and the observer was asked to adjust that color until it matched the test color. This match was, of course, not perfect, since the human eye, like any other instrument, has limited accuracy. It was found by MacAdam, however, that all of the matches made by the observer fell into an ellipse on the CIE 1931 chromaticity diagram. The measurements were made at 25 points on the chromaticity diagram, and it was found that the size and orientation of the ellipses on the diagram varied widely depending on the test color. These 25 ellipses measured by MacAdam, for a particular observer are shown on the chromaticity diagram above.

Extension to three dimensions

A more general concept is that of "discrimination ellipsoids" in the entire three dimensional color space, which would include the ability of an observer to discriminate between two different luminances of the same color.[5] Such measurements were carried out, among others, by Brown and MacAdam in 1949, [6] Davidson in 1951,[7] Brown in 1957,[8] and by Wyszecki and Fielder in 1971.[9] It was found that the discrimination ellipsoids yielded relatively unchanging discrimination ellipses in chromaticity space for luminances between 3 and 30 cd/m2.[6]

Effects in color theory

MacAdam's results confirmed earlier suspicions that color difference could be measured using a metric in a chromaticity space. A number of attempts have been made to define a color space which is not as distorted as the CIE XYZ space. The most notable of these are the CIELUV and CIELAB color spaces. Although both of these spaces are less distorted than the CIE XYZ space, they are not completely free of

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distortion. This means that the MacAdam ellipses become nearly (but not exactly) circular in these spaces.

See also

Metric tensor


1. ̂ Kühni, Rolf G. (March 2003). "6. Historical Development of Color Space and Color Difference Formulas". Color Space and Its Divisions. New York: Wiley. doi:10.1002/0471432261.ch6. ISBN 9780471326700.

2. ̂ Judd, Deane B. (July 1939). "Specification of Color Tolerances at the National Bureau of Standards". The American Journal of Psychology (The American Journal of Psychology, Vol. 52, No. 3) 52 (3): 418–428. doi:10.2307/1416753. JSTOR 1416753.

3. ̂ Wright, William David; Pitt, F.H.G. (May 1934). "Hue-discrimination in normal colour-vision". Proceedings of the Physical Society 46 (3): 459–473. doi:10.1088/0959-5309/46/3/317.

4. ̂ MacAdam, David Lewis (May 1942). "Visual sensitivities to color differences in daylight" (abstract). JOSA 32 (5): 247–274. doi:10.1364/JOSA.32.000247. http://www.opticsinfobase.org/abstract.cfm?URI=josa-32-5-247.

5. ̂ Günter Wyszecki and Walter Stanley Stiles, Color Science: Concepts and Methods, Quantitative Data and Formula (2nd edition), Wiley-Interscience. (July 28, 2000). ISBN 0-471-39918-3

6. ^ a b Brown, Walter R.J.; MacAdam, David L. (October 1949). "Visual sensitivities to combined chromaticity and luminance differences" (abstract). JOSA 39 (10): 808–834. doi:10.1364/JOSA.39.000808. http://www.opticsinfobase.org/abstract.cfm?id=76964.

7. ̂ Davidson, Hugh R. (December 1951). "Calculation of Color Differences from Visual Sensitivity Ellipsoids" (abstract). JOSA 41 (12): 1052–1056. doi:10.1364/JOSA.41.001052. http://www.opticsinfobase.org/abstract.cfm?URI=josa-41-12-1052.

8. ̂ Brown, Walter R.J. (February 1957). "Color Discrimination of Twelve Observers" (abstract). JOSA 47 (2): 137–143. doi:10.1364/JOSA.47.000137. http://www.opticsinfobase.org/abstract.cfm?URI=josa-47-2-137.

9. ̂ Wyszecki, Günter; Fielder, G. H. (September 1971). "New Color-Matching Ellipses" (abstract). JOSA 61 (9): 1135–1152. doi:10.1364/JOSA.61.001135. http://www.opticsinfobase.org/abstract.cfm?URI=josa-61-9-1135.

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LED Tube retrofit story

This is the story of a bank that wanted to cut down operating expenditures. The bank’s management was concerned that such a step might adversely affect the safety of its employees and adversely affect its brand image. “Safety and brand image are non negotiable. Unless we provide a safe working environment to our people we will never be able to attract the best talent. That and the brand image are the biggest drivers of business in the banking world.”

While several steps were hotly debated and many were eventually discarded, installing LED lights was one decision where there was complete agreement once every one saw the projected savings. The area in question was the staircase of the bank. The entire staircase spanned several floors and was illuminated 24 X 7 by 250 fluorescent tube lights. LED tubes provided a 70 % reduction in energy costs – a massive reduction of 113,568 kW per year and resulted in a total annual savings of over $ 125,000 in maintenance and operating costs. Over its lifetime, each modern LED tube would save $3120 in energy costs alone.

"We have access to some of the most sophisticated risk and return analysis techniques. But this was one project where only common sense and basic spreadsheet skills were called into play. The fact that the risk associate with this high return investment is practically nil it makes for a very compelling choice."

The bank had earlier tested the waters with 50 watt halogen down lights and is now planning to replace its 35 watt CFLs in favor of plug in LED replacements. Everyone appreciates the dimmable lights that provide high quality, uniform illumination. The fact that each light will save almost 2 tons of CO2 over its lifespan is an added bonus. “The feeling of being able to do something for the environment is very satisfying. The license to boast about the company’s impeccable environmental credentials comes free.” LED lights demonstrate how modern technology makes to possible to reduce energy consumption, improve the quality of life and get a high return on your investment. With high return LED products in place, many new environment friendly measures can be implemented without any additional budgetary provision, solely from the savings achieved by energy efficient lighting. Once the benefits of modern lighting became apparent many employees of the bank opted for modern energy efficient LED tubes.

"The path to a financially and environmentally secure future of the world is lit by solid state lighting."

ROI and LED Lights - How fast can earn your investment back?

LED lights may turn out to be an instant payback investment, even cash flow positive investment with smart finance options. The savings in energy and maintenance are more than enough to cover the monthly installment of the financing availed to install these lights.

Don’t believe it? Do the math yourself. Here is the summary of such a project.

a) The lighting infrastructure – 50 incandescent lamps of 65 watt each used for 8 hours every day 21 days a month.

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b) LED replacement – 50 LED bulbs each using 9 wattsc) Estimated investment – $ 2000d) Finance variables – 100 % finance at 5.92 %.

And here are the results

a) Loan EMI – $ 22b) Annual loan repayment – $ 265c) Annual Energy savings – $ 677d) Annual maintenance savings – $ 900e) Annual savings in air conditioning costs – $ 118f) Total savings – $ 1430 per annum

It is clear that whichever way you may cut or dice the data you will reach only one inescapable conclusion – LED lights are a great route to save money, improve performance and reduce your carbon footprint.

So Why all the Hype About LED?

So Why all the Hype About LED?

LED lighting is a huge leap in technology which is going to benefit both our environment as well as your spending for household lighting.

The below list gives you an idea of how revolutionary LED lighting is and how it will be the future of household lighting in Australia and around the world.

Light Life: LED lights last up to 50 times longer than a standard Halogen light globe. At 45,000 hours you only need to change the globes once every 30 years.

Efficiency: LEDs produce more light per watt than incandescent bulbs.

Colour: LEDs can emit light of an intended color without the use of color filters that traditional lighting methods require. This is more efficient and can lower initial costs.

Size: LEDs can be very small (smaller than 2 mm2) and are easily populated onto printed circuit boards.

On/Off time: LEDs light up very quickly.

Cycling: LEDs are ideal for use in applications that are subject to frequent on-off cycling, unlike fluorescent lamps that burn out more quickly when cycled frequently, or HID lamps that require a long time before restarting.

Dimming: LEDs can very easily be dimmed either by Pulse-width modulation or lowering the forward current.

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Cool light: In contrast to most light sources, LEDs radiate very little heat in the form of IR that can cause damage to sensitive objects or fabrics. Wasted energy is dispersed as heat through the base of the LED.

Slow failure: LEDs mostly fail by dimming over time, rather than the abrupt burn-out of incandescent bulbs.

Lifetime: LEDs can have a long useful life. LED life is approx. 35,000 to 50,000 hours of useful life, though time to complete failure may be longer. Fluorescent tubes typically are rated at about 10,000 to 15,000 hours, depending partly on the conditions of use, and incandescent light bulbs at 1,000–2,000 hours.

Shock resistance: LEDs, being solid state components, are difficult to damage with external shock, unlike fluorescent and incandescent bulbs which are fragile.

Focus: The solid package of the LED can be designed to focus its light. Incandescent and fluorescent sources often require an external reflector to collect light and direct it in a usable manner.

Toxicity: LEDs do not contain mercury, unlike fluorescent lamps.

Cost Saving: LED lights run on 90% less energy than standard halogen lights, and with up to 50% of a electricity bill comprising of lighting, thats a huge saving over a year.

Efficiency: LEDs produce more light per watt than incandescent bulbs.

Colour: LEDs can emit light of an intended color without the use of color filters that traditional lighting methods require. This is more efficient and will lower ongoing costs.

Size: LEDs can be very small (smaller than 2 mm2) and are easily populated onto printed circuit boards.

On/Off time: LEDs light up very quickly.

Cycling: LEDs are ideal for use in applications that are subject to frequent on-off cycling, unlike fluorescent lamps that burn out more quickly when cycled frequently, or HID lamps that require a long time before restarting.

Dimming: LEDs can very easily be dimmed either by Pulse-width modulation or lowering the forward current.

Cool light: In contrast to most light sources, LEDs radiate very little heat in the form of IR that can cause damage to sensitive objects or fabrics. Wasted energy is dispersed as heat through the base of the LED.

Slow failure: LEDs mostly fail by dimming over time, rather than the abrupt burn-out of incandescent bulbs.

Lifetime: LEDs can have a long useful life. LED life is approx. 35,000 to 50,000 hours of useful life, though time to complete failure may be longer. Fluorescent tubes typically are rated at about

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10,000 to 15,000 hours, depending partly on the conditions of use, and incandescent light bulbs at 1,000–2,000 hours.

Shock resistance: LEDs, being solid state components, are difficult to damage with external shock, unlike fluorescent and incandescent bulbs which are fragile.

Focus: The solid package of the LED can be designed to focus its light. Incandescent and fluorescent sources often require an external reflector to collect light and direct it in a usable manner.

Toxicity: LEDs do not contain mercury, unlike fluorescent lamps.

How does LED Lights measure up?

As time goes on, we see a steady pattern of similar questions and we seem to engage customers with varying degrees of knowledge about LED Lights. Some seem to be experts, and some seem to be new to this new kid on the block. For the most part, we find there is as much good information as misinformation about LED Lighting.

So over the next few months, we are going to talk a bit about LED Lights, all the specs, truths, untruths, where they excel, the truth about lumens, and hopefully dispel some rumors and misgivings. We’ll start with a simple one today: Do you need a frosted LED Tube?

Lately, we are finding that many of the manufacturers are stepping away from frosted LED tubes. When first conceived, there was a specific purpose and need and it had a lot to do with the specific setting and technology being used in early tubes. First generation LED Tubes used first generation DIP Diodes, and in certain office situations, these produced a glare on certain surfaces and computer monitors. As good as LED Lights are in an office environment (no flickering, no humming, no eye strain when compared to their fluorescent counterparts), LED’s did produce a glare that was noticeable and annoying. To combat this, manufacturers started to produce a frosted lens and offered it as an option instead of clear lens’.

However, products evolve, and the latest versions of DIP LED’s and SMD LED are much better than the first version of DIP LED’s, and the need for frosted lens to offset the earliest designs are no longer required. So although tubes are still available with a frosted lens, the need is more for aesthetic reasons than for ones of function.

Think Different, Think Green!

In the United States, the government is encouraging its people into installing energy efficient solar panels in the roofs, windows and other sun-exposed area of the house. The government is offering low-interest financing to aid the people in installing such.

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This act is in accordance with the idea of producing electricity by using alternative energy sources. This is also a campaign into attracting and encouraging people to think green; to think of ways in saving the ailing Mother Earth. This step is just one of numerous possible ways in extending help to the environment.

Photovoltaic solar panels are designed primarily to collect light energy from the sun. This energy excites the electron making it move and cause the depletion area between the PN junctions of the semiconductor to create an electric field. The movement of electrons creates electricity. The electricity created is used to charge the rechargeable batteries connected. The charge of the battery is consumed by all the loads connected to it. Solar power technology is used in secluded areas and areas that can’t be reached by the main power lines, however, now that the campaign to think green is in progress, even in the city, one can find solar panels installed elsewhere. This is with the aim of combining the function of the coal-generated electricity with the solar-generated power. An enormous slash in the electric bill can be experienced by the consumer.

Think green program doesn’t only emphasize the use of alternative energy sources, but also on the utilization of energy efficient loads that will replace the high-energy consuming loads. One cited example of this is on the lighting system. An incandescent lamp of 60W can be substituted by a 5W LED light giving also the same quality of brightness and luminance. By just merely subtracting the power consumed by the two, an unbelievable 55W difference will definitely amaze the consumer and therefore attract more and more consumers to make a big shift and be one of those who supports green living. LED lighting technology has already made a bond with the solar power technology in providing quality and energy efficient lighting. LED solar area lights and LED solar street lights are now available to the consumer. Why LED lights? LED lights were chosen because of the quality and features of the light that it delivers. Aside from an enormous energy saving scheme, LED lights are designed to last for a very long service life. The constant wear and tear experienced by a consumer in the incandescent lamps is totally eliminated in this technology. It is designed to last for around 50,000 to 80,000 hours depending on the frequency and application. Moreover, LED lights do not emit a substantial amount of thermal energy that will likely to end up as thermal pollution (except for LED grow lights). There are a lot proven benefits of LED lighting that one will surely experience.

Thinking something good and beneficial for the environment is definitely an act into hoping and envisioning a lot more worthwhile living here on Earth.

LED – ‘Future of Lighting’

LED lights are a specific type of energy saving, eco-friendly lighting system. LED lights require less amount of energy for their functioning as they generate very little heat, so a much bigger portion of electricity goes into producing light rather than wasting energy. Researches made on LED lights have revealed that they save up to sixty-five percent of energy compared to other lights and bulbs. This kind of energy-efficient lighting is an ideal way for reducing the quantity of carbon emissions in the

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atmosphere. So it can be said that LEDs will ultimately replace all kinds of lighting – fluorescent, halogen, and incandescent in the near future.

LED lights are produced through movement of electrons within its semiconductor structure and lack filaments. This technology is the main reason behind its longevity. A LED bulb can very easily last for ten years. Moreover, they are vibration, moisture, and shock resistant. These lights do not contain harmful substances like lead and mercury and are also free from breaking hazards like shrapnel injuries. All these make them a reliable and safe source of light.

By using a LED light you give yourself a realistic chance on cutting down the expenses towards your electricity bill. Using LEDs you will pay less and gain more. Also it would give you the satisfaction of contributing your little bit in the direction of safeguarding the environment.

These days the LED lights are appearing in different shapes and colors. The colors can range anything from white, blue, yellow, green, and amber. Besides, the color changing LED lights have given the LEDs a new dimension. The shapes are cool, stylish and contemporary. So together with an attractive contour plus the utility aspect, it comes as a complete package in the hands of the consumer.

So spending on LED lights can be termed as a – ‘smart, long-time, eco-friendly investment.’

Why LEDs - LED vs HID

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LEDs have received much recognition because of the energy and dollar savings associated with them; but there is another revolutionary benefit that some may not know about. LED light fixtures with micro-processors have the ability to communicate with modern computer technology. This means that a “smart grid” system can be utilized to program, monitor and control the fixtures from a remote location. The implications of this are vast and all the possible capabilities will reveal themselves as time goes on and these systems are developed. Sheenly Lighting intends to be a pioneer in this new realm and we are excited to implement our ideas to create safer and more efficient cities

Why LED lighting provides economic benefit while reducing CO2

Energy conservation and the global movement towards CO2abatement.

Scarce resources and climate change are now two of the world’s greatest concerns. Although there are several arguments on the scientific evidence, the implications ultimately equate to those driven by the global energy depletion issue, which is indisputable. McKinsey has been working on this topic for several years from the perspective of climate change, and has developed a global greenhouse gas (GHG) abatement cost curve that offers a very holistic perspective on GHG abatement activities. These initiatives are in essence very much the same as those required for energy conservation (Exhibit 4).

Analysis using the GHG abatement activities reveals that replacing current non-energy-efficient light

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sources with energy-efficient light sources will provide substantial economic benefit while at the same time reducing CO2. In contrast, most other CO2 abatement activities will have a negative economic impact. Replacing incandescent lighting with LED to reduce 1 t CO2 per year in 2015 would provide an economic benefit (calculated as total cost of ownership) of around EUR 140 per 1 t CO2. Achieving the same CO2reduction by introducing solar power would cost around EUR 80 per 1 t CO2(Exhibit 5).

Replacing traditional light sources would also require less capital investment than for solar power. The investment for substituting incandescent or CFL lighting with LED is a fifth of the investment for installing solar power, calculated on a t CO2e p.a. basis, which means subsidizing LED is a more efficient investment than subsidizing solar power from a government perspective.Replacing traditional lighting technology with energy-efficient technologies such as LED is therefore much easier and represents much sounder economics for reducing CO2emissions than other CO2 reduction activities. By and large, populations have now adjusted to the fact that the average price of lighting products will increase. Energy efficiency is the driving force that will contribute most powerfully to the upcoming discontinuity in the lighting industry.

Now you will be convinced why people starts to use LED panel light, it saves CO2 and money!

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(Source: McKinsey - The Global Lightmarket Study 2012)

Office LED Lights Increase Workplace Productivity

As part of the ‘Workplace Issues’ series, a study was conducted on the effect of quality lighting in the workplace and found that inefficient lighting could lead to workplace injuries such as eyestrain and even musculoskeletal injuries. The survey noted that two out three participants experienced physical problems due to an inadequately lit environment. Of course, as we all know, an employee experiencing discomfort (and especially one on sick leave) is likely to result in decreased productivity. Modern companies might be focussed on investing in impressive architecture, state-of-the-art technology, and organisational psychologists but perhaps they should revert to the scientific method of management – and ensure they’re meeting the basics of proper lighting first.

LED lighting is the most obvious choice for adequate yet energy efficient office lighting, with directional light emission, its resistance to mechanical failure, instant-on at full output, rapid on-off cycling capability without detrimental effects, improved performance at cold temperatures, dimming and control capability, minimal non-visible radiation (e.g. ultraviolet, infrared) and superior lifetime. Most importantly for an organisation’s bottom line – LED lighting is a very profitable investment and is easily fitted into existing light fixtures too.

With a greater emphasis on knowledge-intensive work and a trend towards working from home in current times, the way people work is changing and companies need to incorporate lighting and furniture in an intuitive way to encourage employees to work in the workplace and to be productive when working.

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Sheenly Lighting is in full support of creating a healthy and productive working environment through energy efficient workplace lighting. now Sheenly LED panel lights have been widely chosen for lots of office lighting projects in China, Germany, UK, and many other locations.(sheenly.com)