Favorite Set Home Chinese English
Keywords:
 
Home >> Why LEDs ?

 

Save Money. Buy Green. Create Low Carbon with LEDs

 

1. Longevity

 

LED's last 50,000 hours or more. Most home owners using their lights 3 - 4 hours a night will never have to replace them ! for some commercial lighting Operating 12 hours per day, the LED should last for over 8 years or more, they never has to replace them . LED’s are nearly 8 times that of incandescent lights, and 4 as high as compact fluorescent lights.  

 

2.  Low Power consumption, High Efficiency

 

LEDs use up to 80% less power than conventional light sources, including incandescent or halogen. Incandescent bulbs. The light output is comparable to that of a 40 to 100 watt incandescent light. Our LED lighting provides efficiency and enables consumers to save hundreds over the life of the light, without compromising beauty or the environment.

 

3.  Low Heat

 

LEDs product less heat relative to other conventional light sources and will not increase the temperature of the surrounding environment. Since most of the power used is converted into light, minimal heat is produced and touching an LED light source will not burn one’s fingers. This low heat emittance makes LEDs ideal for retail environments as well as illuminating heat sensitive products such as cosmetics or chocolate.

 

4. Durability

 

Unlike incandescent, HID or fluorescent lamps, rubbing, intense movement or vibrations to the fixture should not affect the performance of LEDs.

 

5. No Infrared or UV Radiation

 

LEDs do not produce infrared or ultraviolet light. This makes LEDs especially ideal for illuminating precious artifacts, paint, , , , , , , , , ings, clo, , , , , thing, or other items that are , , susceptible to fading or deterioration due to UV rays.

 

6. Safety and security

 

Led lights, operate at much lower temperatures. Halogen and incandescent lights are hot enough to cause fire, and they frequently do. Led lights also emit no damaging ultraviolet so they will not cause fading and aging of artwork or other sensitive materials. Fluorescent and halogen lights can cause significant damage over time.

 

7. Save energy

 

LED Lights uses only 10% on average of power. That's 90% less energy spent per incandescent light, and 50% less than a CFL. Save Energy, Save Money.

 

8. Eco Friendly

 

You'll never again have to choose between inefficient incandescent and fluorescents that contain mercury. LED lighting is safe, environmentally friendly and contains no toxic mercury.

 

LED lights use 90% less energy than conventional incandescent bulbs and less than half the energy of compact fluorescent lamps. Consuming less energy results in fewer greenhouse gas emissions being released into our environment.


LED product, s are designed to last for 50,000 or m, ore hours, there is less waste generated from used or burnt out light bulbs, some of which may contain Mercury.
Our LED Lighting products are mercury-free and require no special disposal procedures.

 

9. No More Maintenance

 

Constantly changing LED lights are costly especially for business, this cost is drastically reduced due to the life span of LED Lights.

 

10. Versatile Applications

 

LED light applications (LED applications are endless......)

There is a wide range of general types of applications for LED lighting. Some include:

 

*  General indoor and outdoor illumination

*  Architectural illumination

*  Commercial/residential directional lighting

*  Stage lighting

*  Reading lamps

*  Spotlights

*  Sign and symbol luminaries

 

11.  Beauty and Colors Fully Revealed


LED lights have a higher color rendering, so everything under them looks more vibrant and life like. Choose warm white or white lighting. 
 

 

LEDs: An Introduction

 

 

A Light Emitting Diode (LED) is a semiconductor device that produces light when current is passed in one direction. Light is produced from the energy conversion that occurs in the LED structure, much like a tiny light bulb. However, due to their semiconductor-based structure, LED lights are much more rugged and damage resistant than ordinary light bulbs and fluorescent tubes.

 

When beginning to craft a luminaire, the choice of basic light source requires the consideration of many factors. LED technology is quickly advancing, as is the demand to integrate LEDs into more types of products. Methods for powering LEDs differ greatly from methods used in other types of lighting, so there are many important concepts and design considerations that must beunderstood.

 

There are many significant benefits to working with LEDs; energy conservation. is one of the most widely known. A direct comparison of LEDs to other prevailing lighting technologies, such as incandescent and fluorescent, indicates the energy savings that can be realized. Incandescent light uses the most energy, fluorescent is second, and LEDs are the most efficient of the three.

                                    Figure 1: Generic Lighting LED

 

Basic LED Lighting Concepts

 

Chromaticity

Chromaticity provides an objective value of the quality of a color without regard to luminance. Chromaticity is therefore determined by hue and depth of color (i.e., saturation and chroma).

 

 

 

Lamp Uniformity

Lighting uniformity affects our perception of environment and our ability to navigate it. Uniform lighting allows us to perceive the environment continuously and without sudden breaks caused by lighting level drops.

Lighting and illuminance uniformity is an important factor in outdoor applications as well. On roads the illumination must avoid low uniformity ratios: the frequent changes of contrasting high- and low-lit road segments cause enormous eye discomfort, leading to stress and tiredness and therefore jeopardizing road safety.

 

 

Lighting uniformity affects our perception of environment and our ability to navigate it. Uniform lighting allows us to perceive the environment continuously and without sudden breaks caused by lighting level drops.

The illuminance level and its uniformity on room surfaces can be expressed as a ratio of highest- to lowest-illuminated area in a given room or space. The closer to one it is, the more uniformly lit the space is. The uniformity calls for a luminaire with very wide curve of lighting verging on the diffused and constant light scattering in all directions. With such a high uniformity comes also a perception of boredom to the space, as the lighting itself lacks any contrast and dynamism.

The uniformity also depends on the types of luminaires used, their spatial position and their number. Again the EN 12464-1 standard requires certain tasks to be provided with a certain uniformity of lighting. Just like in the case of glare and task area illumination, technical drawing is the most demanding, requiring a uniformity index of at least 0.7. Other focus-intensive tasks demand a ratio of 0.6.

Lighting and illuminance uniformity is an important factor in outdoor applications as well. On roads the illumination must avoid low uniformity ratios: the frequent changes of contrasting high- and low-lit road segments cause enormous eye discomfort, leading to stress and tiredness and therefore jeopardizing road safety. Human eye takes its time to adapt to new lighting conditions and frequent changes can for example cause some objects to be invisible. In the case of people such ignorance can have tragic consequences.

Lighting uniformity can again be achieved using sensors and other control mechanisms. A quality dynamic lighting system will be able to provide desired uniformity under changing circumstances, e.g. during daytime when sunshine can be the primary light source. The role of the artificial light is then keeping the uniformity as constant as desired by lighting those spaces that are further away from the windows and other sources of sunshine, such as skylights.

Uniformly lit environment also provides eye comfort for those working with PC screens, which are by themselves light sources. The lighting should take this fact into account and provide such level of illumination that does not create abrupt changes in illuminance between screen and the rest of the room. The uniformity according to the standards does not distinguish between task area, its surroundings and the background. To fulfil the criteria of the standard all parts of the room have to be taken into account.

As with previous criteria, for LQS purposes a solution receives perfect 5 points if it complies with the criteria of the standard, otherwise it gets a zero . 

In an LED (and especially with white LEDs that use phosphors to achieve their white color), color temperature can easily vary due to a number of factors. The variations can be visible to the human eye [Figure 2], even though the devices have the same Color Temperature (CCT) rating. Physical variations can include: phosphor composition from batch to batch, fixture materials, operating junction temperature, forward current, fixture or cover materials (if used), heatsink design, and manufacturing quality. Electrically, the LED’s color temperature in pulsed applications can be affected by its forward current and duty cycle. To identify variances and ensure consistency within a specific set of devices, LEDs are “binned,” or sorted, during manufacturing into sub-groups with similar color coordinates. Binning defines an LED’s spectrum via a set of X and Y chromaticity coordinates. The “tightness” of these specifications’ color measurement varies by vendor.

 

Figure 2: LED color Uniformity: This curve is based on the Macadam Ellipse which shows
the human eye’s ability to see a change in color. The dark curve is a Black Body Curve which
is temperature dependent. The ANSI binning follows the Black Body Curve and shows the
possible variations for color temperature (industry standard color bins are shown).

 

A wide color temperature ranges of 3000K~12000K (Kelvn)

 

2500-2600K (Kelvin) - Special warmer pink

 

2700-3000K (kelvin) - warmer yellow

 

4000-4500K (Kelvin) - more neutral "daylight color" - most commonly used in office buildings

 

5000-6500K (Kelvin)- more cool white "white bluish"

 

7000-12000K (Kelvin) -more sky white bluish - most commonly used in special signages

 

Color rendering index

The appearance of colored objects is affected by the interaction between the colors. The effect a light source has on the appearance of colored objects is described by its color rendering properties. These are grouped into grades based on the “general color rendering index” CRI.

The color rendering index indicates how closely the color of an object matches its appearance under the relevant light source. To determine the CRI values of light sources, fifteen defined test colors commonly found in the environment are each illuminated under the reference light source (CRI = 100) and then under the source being evaluated. The greater the difference in the appearance of the test colors rendered, the poorer the color rendering properties of the light source under examination.

Light and color define the atmosphere of a room and influence our mood and sense of human well-being by their perceived “warmth” or “coldness”. Guaranteeing correct color perception under artificial light forms is a very important part of the lighting designer‘s task.

The appearance of colored objects is affected by the interaction between the colors - i.e. the spectral reflectance of the objects we see and the spectral composition of the light illuminating them. In everyday life, we come across surface colors which can differ in appearance depending on how they are illuminated but which we recognize for what they are thanks to stored visual experience independent of lighting type.

For instance, we have a stored impression of the color of human skin in daylight. Where artificial lighting lacks a particular spectral color or exaggerates certain colors in its spectrum (as is the case with fluorescent lamps with CRI 80), skin seen under it may appear a different color but will still look “natural” because of empirical compensation.

An extreme and most obvious example would be the ultra-violet lighting: it makes white extremely bright, the teeth glossy and the skin tone appears extremely tan. Of course, the extreme effect is obvious and the eye therefore knows that the colors are artificially shifted.

The effect a light source has on the appearance of colored objects is described by its color rendering properties. These are grouped into grades based on the “general color rendering index” CRI. The color rendering index indicates how closely the color of an object matches its appearance under the relevant light source.

To determine the CRI values of light sources, fifteen defined test colors commonly found in the environment are each illuminated under the reference light source (CRI = 100) and then under the source being evaluated. The greater the difference in the appearance of the test colors rendered, the poorer the color rendering properties of the light source under examination. In theory the CRI can go below zero, but such a result is discarded as the color rendering of such source provides no useful data.

Under a light source with a CRI of a 100 all the colors have the same optimal appearance as under the reference light source. The lower the CRI index, the poorer the rendering of the surface colors of the illuminated objects. In practical use CRI is an important aspect when choosing light sources. Those designated standard are cheap, but th, , eir CRI can reach only 60 or even less. The standards defined in EN 12 464-1 demand CRI of at least 80 for living spaces, inferior light sources are to be used only in corridors or storage spaces where color rendering is of much less importance.

     

In several industrial sectors the demand for correct color rendering is even higher, requiring light sources of CRI above 90. This is especially important in printing presses where correct color assessment is vital, but can be as important in retail or in shop windows to correctly sh, ow the potential customers the color of clothing, for example. For such shops the correct color rendering is important also in the cabins where the customers try the clothes on. Wrong illumination there can lead to lower sales, with customers not being able to see the color correctly. For LQS purposes, highest marks are awarded for CRI at or over 90 . 

Harmonious distribution of brightness

Brightness is a complex factor that can be defined as an illuminance of a surface as perceived by a human eye. In such a definition brightness can be expressed as a ratio of luminous intensity of a surface under certain angle to the surface area of its projection. Brightness is a directional unit, depends on luminous intensity in different directions and directional reflectiveness of a surface and the projected area of a surface in a given direction. Harmonious distribution of brightness is important for sharpness of vision and sensitivity to contrast, contrast being relatively small differences in brightness. Setting the brightness too low can again cause strain, decrease the visual stimulation and therefore also work performance. Darker surfaces in the room can work against the harmonious distribution of brightness and can cause feelings of oppression and anxiety.

Human vision is the most important sense for gathering information; the brain gets 80 percent of all information from visual cues. The quality illumination is the key to process and gather the information correctly. Brightness is the only factor to which our eye reacts. Correct illumination should therefore take distribution of brightness into account. The eye has different sensitivity of vision depending on the angle.

 

The most sensitive part is at 10 to 20 degrees from horizontal axis. In this section high brightness is to be avoided, as it could cause glare, which has negative consequences on well-being, comfort levels and health. In the case of glare the pupil is contracting, decreasing the perception and the ability to discern brightness levels. Quality of luminaires can help with the brightness distribution, but the interior design plays its part as well: proper furnishing of the space and the materials used affect harmonious distribution of brightness.

 

Brightness is a complex factor that can be defined as an illuminance of a surface as perceived by a human eye. In such a definition brightness can be expressed as a ratio of luminous intensity of a surface under certain angle to the surface area of its projection. Brightness is a directional unit, depends on luminous intensity in different directions and directional reflectiveness of a surface and the projected area of a surface in a given direction. Its unit is candela per square meter.

 

Brightness per unit area
Technical symbol: L
Unit: cd/m2

 

The standard light-related value for the impression of lightness is the brightness per unit of area, because only the eye perceives it. It is derived from the directed stream of light in relation to the perpendicularly illuminated area of the recorded solid angle.

 

Harmonious distribution of brightness is important for sharpness of vision and sensitivity to contrast, contrast being relatively small differences in brightness. Eye strain can be caused by too high a brightness, which can cause glare and too large contrasts in brightness, where eyes need to constantly adapt to significantly different lighting conditions. Setting the brightness too low can again cause strain, decrease the visual stimulation and therefore also work performance.

 

To achieve uniform brightness distribution all surfaces have to be taken into account and their brightness calculated. Once again, achieving optimum brightness conditions is a task for interior designer as well, as he needs to choose brighter colours for interior surfaces, walls and ceilings. Darker surfaces would work against the harmonious distribution of brightness and can cause feelings of oppression and anxiety.

 

The standard EN 12464-1 actually calls for specific reflectance of surfaces: for ceilings it is 0.7 to 0.9, the walls 0.5 to 0.8. The floor is the least important factor from the brightness and reflectance point of view, with required reflectance only 0.2 to 0.4. On the other hand, even furnishings and machinery are limited in their reflectance to 0.2 to 0.7. Which means they should not be much brighter than the walls, but also not too dark, as this works against the proper brightness distribution.

 

The main surfaces should be illuminated uniformly as well. The minimum illuminance of walls is set at , 50 , lux with uniformity over 0.1; the ceilings have their minimum at 30 lux with the same uniformity. Unlike the other factors, LQS awards 0 to 5 points based on illuminance level and its uniformity on room surfaces: the highest marks demand illuminance of walls of over 150 lux with uniformity of over 0.3. Same contrast is required for ceiling with illuminance over 75 lux. This is stricter than the EN 12464-1 standard requirements . 

Illumination level

 

 

 

The illumination also affects the psychological well-being of a person depending on the luminance of the luminaire, chromaticity of lighting, uniformity of luminance and colours used in the environment itself. The correct lighting should be able to convey information necessary to carry out work tasks, to motivate, to set positive mood or creative atmosphere. The opposite then creates a probability of failure, injury, eye strain and tiredness.

 

Great care should be taken to avoid the possibility of eye strain, which leads to safety threats. This can be caused not only by improper illumination level, but for example also by flicker of fluorescent light, caused by faulty or cheap electronics that is driving these light sources.

 

Task area is the most important space in terms of illumination quality. The illumination of the task area should take into account the type of work being done, the focus it takes to carry out the task and also other demands. While the correct illumination of the task area is of paramount importance, for the human well-being also its immediate surroundings have to be taken into account.

 

Comfortable working or living environment can be beneficial for work productivity and the ability to relax and regenerate. The employee should feel well in his working environment. Illumination is an important factor to provide such comfort, improving the performance while reducing the risk of injuries from either bad visibility or stress caused by uneven illumination levels across workplace.

 

The illumination also affects the psychological well-being of a person depending on the luminance of the luminaire, chromaticity of lighting, uniformity of luminance and colours used in the environment itself. The correct lighting should be able to convey information necessary to carry out work tasks, to motivate, to set positive mood or creative atmosphere. The opposite then creates a probability of failure, injury, eye strain and tiredness.

 

Great care should be taken to avoid the possibility of eye strain, which leads to safety threats. This can be caused not only by improper illumination level, but for example also by flicker of fluorescent light, caused by faulty or cheap electronics that is driving these light sources. Low frequency flicker at 50 Hz is especially tiring and can lead to repeated errors and severe eye strain, which in the end may require medical attention. In such case replacement of the luminaires for higher quality ones is advised.

 

In extremely sensitive persons the frequent flicker can even lead to epileptic seizures. With increased tiredness the probability of epileptic seizures increases as well, making these faulty set-ups a health risk especially in larger areas with many workers. Such lighting failures can also produce unwanted effects in retail areas and in every other environment where a significant number of people are present.

 

For optimum performance the goal should be to mimic natural light as closely as possible or to even utilize it. This could be tricky given that prevention of glare is also required and glare-reducing glass finishes may negatively affect the quality of light.

 

Persons with disabilities may have different demands for illumination levels to carry out their tasks correctly, calling for dynamic lighting systems. These can adapt to the requirements of different types of workers. With digitally controlled lighting this task is even easier to achieve, further removing obstacles for employing disabled or elderly persons. For the visually impaired there can be stricter demands on illumination or contrast levels.

 

To keep illumination level constant and in line with the standards lighting sensors can be employed. These can keep the illumination levels constant even with deterioration of light source quality over time. Daylight sensors can then help mix artificial and natural light, keeping the illumination level constant as desired while helping to achieve significant energy savings during sunny days.  

Luminous Efficacy

Luminous efficacy is a description of how well a light source can provide visible light from a given amount of energy. A comparison of the luminous efficacy of common lighting types would show that fluorescent light is better than incandescent, and an LED light source is better still.

 

Luminous Flux

Luminous flux provides a measurement for the perceived power of light. Very different from radiant flux, which shows the total power of light emitted, luminous flux is adjusted to the various wavelengths of light as perceived by the human eye.

 

Luminous flux can be used as an objective measurement of “useful” power (i.e., that which creates light the human eye can actually perceive). This parameter can be found on some light bulb packaging and can be used to compare the luminous flux of one light source to another.

 

Macadam Ellipse

As stated in its classic definition, “The 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.” In other words, the Macadam Ellipse defines the minimum color change that the human eye can perceive.  

LED Advantages

 

LED bulbs offer a number of significant advantages over other lighting types. Ones longer operating life; up to 50,000 hours to half brightness with LEDs. This is 60% longer life than an average long-life sodium-vapor commercial luminaire.

 

LEDs also offer increased durability because they are solid state devices, and LEDs also offer more design flexibility given their small footprint and freedom of placement. For instance, certain types of arch lighting and other creative lighting solutions that mount lights on curved surfaces are newly enabled by LEDs.

 

The growing popularity of LEDs is also linked to their benefit to the environment. They require little energy to operate, and lack hazardous materials such as Mercury (Hg). It is likely that the adoption of LEDs into lighting designs will continue to increase due to their earth friendliness, driven by both customer awareness and increasing legislation related to energy conservation.

 

An example for Led bulbs Vs CFL bulbs Vs Incandescent bulbs to leads us know energy-saving lighting solution. for a brighter and greener future...

 

Comparison Table (based on 1 lamp for 1 year)

INCADESCENT BULB

50W

LED BULB

10W (avg)

Luminous intensity

775 lms

850 lms

Yearly running cost (based on 8 hours a day 25c/kWh)

$49.14

$9.00

Life span

2,000 hours

40,000 hours

Replacement needed

Less than 1 year

over 10 years

Greenhouse emissions (CO2-e tonnes/year)

142

34

Payback (based on average cost $45 per lamp)

0.9 years

 

LED lighting isn't a new technology; in fact, it has been with us since the 1960's. LED light bulbs were originally used as a replacement for incandescent indicators and displays in laboratory equipment and eventually in TV's, watches, radios and calculators.With the current looming energy crisis in Australia, Italy, France , Newzeland and so on, and pressure exerted on governments and businesses alike for more sustainable energy solutions, LED lights have a bright future in space lighting solutions.

Copyright ©2007-2016 Shenzhen FINE LED Lighting Co.,Limited All Rights Reserved||UL|CE|ROHS|ISO9001|5 YEAR WARRANTY|
Tel:(+86) 755-25432561 Fax:(+86) 755-25521401 Add:B-1205 Jihao Building,NO.1086 Shennan Road East,Shenzhen,Guangdong, P.R.CHINA
Visits:2540468 [Management]