Benefits and Uses of LED Lighting

Are you looking for state-of-the-art LED lighting? This article will educate you about some of the most noticeable benefits of these small yet powerful lights in terms of cost effectiveness and environmental uses. LED is short for Light Emitting Diode. LED lights are made up of small semiconductor diodes that emit blue, green and red light when an electric current is passed through them. Using these three basic colors, all other colors can be produced by combining them in different proportions. Basically these types of lights are used as indicators and for other special purposes like Christmas lighting and for use in flashlights and car lights.

Because LED lights are very efficient in terms of saving energy and cost, they are popular all over the world. All kinds of LED lights are provided by renowned manufactures across the globe. These lights include high-power LEDs, low-power LEDs, sign displays, remote control devices, household bulbs, car kits, rope lights and strips. White-colored LED lamps and energy-saver lights are very common and good at their job. They can operate continuously for hours and hours without becoming dim or weak. High-power and strong LED lights are expected to last for many years.

LED industry leaders have estimated that good quality LED lighting can last for 50,000 to 100,000 hours. Usually these kinds of lights require 9 to 14V DC power which is very low as compared to power required by traditional lighting. Furthermore, they are easy to install and carry around in case you need to move to a new place. They 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 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.

Although LEDs are more expensive than other type of lighting, they are very cost effective in the long run. First of all, they save energy. And secondly, they operate for a much longer duration than ordinary fluorescent lights or tubes. Their design flexibility, powerful nature, small size and availability in almost all kinds of colors make them an attractive choice for household use. They are also safe to be used around children as they do not produce much heat. Visible LEDs do not produce any ultraviolet radiation and are therefore useful for a wide range of purposes.

So, you see LED lighting has many advantages over other types of lighting. It is not only cost-effective but also very safe and useful. Different kinds of LED bulbs are now utilized for household use to produce super bright and continuous light. They 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. 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.

Source:http://www.articlesbase.com/electronics-articles/benefits-and-uses-of-led-lighting-513633.html

New Concept of Green & Energy-saving Lighting - LED Light

LEDs are solid-state semiconductor devices that convert electrical energy directly into light.
Thermal sources of light such as flames and incandescent filaments emit light when heated, either by chemical reaction (flames) or electrical heating (filament lamps). LED "cold" generation of light leads to high efficacy because most of the energy radiates within the visible spectrum.
Other common high efficiency light sources, such as fluorescent lamps and electro luminescent devices, also produce light without much thermal radiation outside the visible spectrum.
Because LEDs are solid-state devices, they can be extremely small and durable; they also provide longer lamp life than other sources.

Light is generated inside the chip, a solid crystal material, when current flows across the junctions of different material compositions.

An LED consists of two elements of processed material called P-type semiconductors and N-type semiconductors. These two elements are placed in direct contact, forming a region called the P-N junction. The composition of the different materials determines the wavelength and therefore the colour of light generated.

LED resembles most other diode types, but there are important differences. The LED has a transparent package, allowing visible or IR energy to pass through. Also, the LED has a large PN-junction area whose shape is tailored to the application. The device shown in Figure 1 is an AlGaInP LED because the semiconductor layers are aluminum (Al), gallium (Ga), indium (In), and phosphate (P).

Main LED materials
The main semiconductor materials used to manufacture LEDs are:
*Indium gallium nitride (InGaN): blue, green and ultraviolet high-brightness LEDs
*Aluminum gallium indium phosphide (AlGaInP): yellow, orange and red high-brightness LEDs
*Aluminum gallium arsenide (AlGaAs): red and infrared LEDs
*Gallium phosphide (GaP): yellow and green LEDs

Why LEDs?

LEDs have a range of benefits which is fast making them the best solution for real energy efficient lighting. Over the course of the next few years some aspects are expected to change significantly.

Lifetime
As solid-state light sources, LEDs have a very long lifetime and are generally very robust due to no mechanical or moving parts.
Incandescent bulbs have an expected lifetime of 1k to 5k hours, while good quality LEDs are often quoted of having a lifetime of 50k hours, more than 5 years continuous use. However it is important to to understand that the performance of LEDs degrades over time, and this degradation is strongly affected by factors such as operating current and temperature.

Low maintenance
The long lifetime of LEDs reduces the need to replace failed lamps, and this can lead to significant financial and environmental savings, particularly in maintenance, labour and recycling. This makes LED fixtures useful for installations in inaccessible locations, but if tasks like cleaning the light fixture are required, then the light sources could be replaced at the same time, negating the "low maintenance" advantage.

Efficiency
As a semiconductor device, LEDs are highly efficient. Current device technology is allowing the performance of these to be pushed to limits that exceed that of standard lighting.
The directional nature of light produced by LEDs allows the design of luminaires with higher overall efficiency.

Low power consumption
The low power consumption of LEDs leads to large energy savings that can often drive the installation of LED-based systems. Initial purchase costs start off higher, but can be proven to return the investment cost in a short period of time.

Brightness
Light outputs are constantly being increased and there are several products that have higher lumen output than traditional lighting.

Heat
LEDs do not produce heat in the form of infrared radiation (IR) unlike incandescent bulbs which makes them hot to the touch.
This lack of heat production allows LED fixtures to be used in locations where heating from conventional sources would cause a particular problem e.g. illuminating food, textiles, artifacts, etc.
However, LEDs do produce heat at the semiconductor junction within the device and good thermal management must be employed on high power devices to maintain operation life

Cost
In many applications, LEDs are expensive compared with other light sources, when measured by metrics such as “£-per-lumen”.
LED manufacturers continue to work towards reducing their production costs while at the same time increasing the light output of their devices.
However, the high initial cost of LED-based systems is offset by lower energy consumption, lower maintenance costs and other factors.
The initial cost may seem high, but take into account the electricity usage that is saved, they pay for themselves.

Electricity Cost savings from switching to LED Direct replacement bulbs
10W LED Bulbs Vs 75W halogen bulb running cost comparison

Small form-factors

LEDs are very small - typical high-brightness LED chips measure 0.3 mm by 0.3 mm, while high-power devices can be 1 mm x 1 mm or larger. There are many examples where the availability of small, high-brightness devices have enabled significant market advancement. The obvious example is in mobile phone handsets, where blue, green and white LEDs are now used in most models to back light keypads and liquid-crystal display (LCD) screens.

Instantaneous switch-on
LEDs switch on rapidly, even when cold, and this is a particular advantage for certain applications such as vehicle brake lights.

Colour
LEDs are available in a broad range of brilliant, saturated colours (although performance varies across the spectrum), and white devices are also available. Modules containing different colored LEDs (typically red, green and blue, or RGB) can be tuned to a huge range of colours, and easily dimmed. RGB modules provide a much wider gamut of colours than white LEDs or other traditional white light sources, which is a particular advantage in applications such as backlighting liquid-crystal displays (LCD's).

RGB LEDs and colour mixing
LED characteristics change with time, temperature and current, and from device to device. For RGB LEDs, the performance of different colored devices changes at different rates. This can result in variation of lamp colour and intensity, and poor reproducibility.



LED Vs Halogen

LED Lighting Types

Now the LED bulbs are widely applied in household, office, street, shop, park etc for decoration and lightings LED lighting family mainly includes:
1. LED ball lamp
2. LED spot lamp
3. LED ground lamp
4. LED tube light
5. LED rope lamp
6. LED pool lamp
7. LED curtain lamp
8. LED Christmas (festival) lamp
9. LED ceiling lamp
10. LED road light
11. LED Solar light
Etc.

In a word, LED lightings will be the future of lighting, and it will definitely replace the halogen lights in soon future.

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Solar Flood Lights – Provides Much-needed Illumination

Solar outdoor lights are becoming more popular among home and property owners. Such gadgets that are considered standouts are the solar flood lights. A home owner usually utilizes lighting in order to provide more illumination to the landscape, especially during nighttime. Likewise, another concern when employing lights is to enhance security and safety around your property.

As conventional lighting that uses electricity can become a cause for you to pay higher utility bills, a good alternative are solar outdoor lighting. Sun powered products such as solar powered flood lights are quite easy for anyone to install given the simple and few parts that they have. Albeit, the latest in the solar technology as made the solar flood lights brighter and more efficient.

Flood lights can effectively provide better and more enhancing lighting. It is meant to highlight any garden feature or structure. Likewise, such lights can be depended on in providing sufficient illumination on the dart spots in your home exterior or garden.

For those who are skeptical when it comes to the quality as well as performance of the solar powered flood lights, it is known that the improvements in bulbs as well as solar lighting technologies have made great strides.

The fact is that many commercial and production firms who require lights on their surroundings especially during the nighttime are now using solar flood lighting.

Many of these firms not only want to save on utility expenses, and more so, they are concerned about the environment. Evidently the alternative form of energy that is solar is every environmentally friendly and does not produce and release harmful products such as carbon in the air.

Solar flood lights, indeed, can be provider of lights for aesthetic purposes. It can effectively accent any feature of the outside areas of a home property. But for many, the security that it gives is good enough reason for a home owner to install these outdoor solar lighting.

For more solar flood lights, solar powered shed lights and other articles on outdoor solar lighting, do visit us at Solar Lights and Gizmos blog.

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Halogen, Heat, Hype and Hysteria

by Eric Strandberg LC,

Lighting Design Lab

As halogen light bulbs (lamps) gain more market share and find their way into more residential applications the controversy around them continues. Some marketers make questionable claims about their products. (The Lab has a 300W torchiere on display that is boldly labeled "Environmentally Responsible Lighting"…which, by the way, couldn't be farther from the truth). Safety and consumer groups urge caution about the hazards of halogen sources for reasons ranging from excess heat to ultra-violet emissions.

This article attempts to put some of these issues into perspective and to dispel some myths.

Myth #1: Halogen is much brighter. True and False. In the case of directional sources such as PAR lamps and MR16s (low voltage), the halogens have a much higher center beam candlepower (CBCP), largely due to more precise beam control, than non-halogen PAR or R type lamps. Lets look at some 30 degree "flood" lamps (note the longer lamp life too).
65 watt PAR standard- 1700 CBCP, 1750 hours
60 watt PAR halogen- 2500 CBCP, 3000 hours
50 watt MR16 low voltage halogen- 2500 CBCP, 6000 hours

However in the case of 'A' style lamps (standard omni-directional lamps) the brightness difference is just about a wash, with the halogen lamp providing only about 10% more lumens. But the halogen does have about twice the lamp life.

100 watt standard- 1700 lumens, 1000 hours.
100 watt halogen- 1850 lumens, 2250 hours (see note 1 below).
When comparing higher wattage lamps, the standard incandescent is actually brighter.
300W "A" standard- 6200 lumens, 750 hours
300W T-3 halogen- 5950 lumens, 2000 hours.(commonly used in torchieres)
For fixture designers the big advantage with halogen is small size. The 'A' lamp is about the size of an lemon and almost 7" long while the T-3 halogen is about as big as a string bean. This brings us to myth #2.

Myth #2: Halogen is hotter. True and false. A 300W incandescent lamp gives off the same amount of heat regardless of its size, shape or type. However because most halogen lamps are small they have very little surface area and their bulb wall temperatures can be extremely high. This can lead to the fires in which halogen torchieres are so notorious. Many of the modern low voltage desk lamps have a 50W halogen bulb smaller than a peanut. Compare it to an "A" lamp (the size of a lemon) and its not hard to imagine which would give you a burn faster due to less surface area. However, if properly used and shielded, the small halogen lamps can make for interesting and safe fixture designs. Another way in which halogen can be perceived as hotter is through light concentration. As stated earlier, the halogen PAR lamps have more precise beam control resulting in more light and heat being directed in the beam angle. This brings us to myth # 3.

Myth #3: Halogen is more efficient. True and false...mostly true. For the most part the halogen products deliver more lumens per watt than conventional tungsten lamps. But it is up to the user to apply the appropriate wattage to achieve the proper light levels. A 75W halogen PAR30 uses just as much energy as the 75W R30 it replaces. (It will be brighter, which may or may not be a good thing.) I cringe when I see one of those square halogen floods being used to light a small parking area. These fixtures are usually at least 300W and unless you are planning to do surgery in the parking lot it is far more light than needed for most tasks. Probably the most efficient of the halogens is the low voltage MR16 (but not for parking lots).
Lets compare some common 50W lamps with similar beam spreads:
50ER30 = 1200 CBCP, 2000 hrs
50PAR30/H = 2000 CBCP, 2000 hrs
50PAR30HIR 2 = 3000 CBCP, 3000 hrs (see note 2 below)
50MR16 = 3160 CBCP, 5000 hrs!
Remember, these all use the same amount of power! The savvy designer may use a lower wattage lamp or use a wider beam spread and less fixtures.

Myth #4: Halogen is an ultraviolet radiation (UV) hazard. False and true, mostly false. A standard incandescent lamp emits about 75 micro watts per lumen(µW/lm) of UV, and unshielded halogen emits 100- 200 µW/lm. (Compare this to daylight, which emits 300 - 600 µW/lm!) However Underwriters Laboratories now requires halogen lamps and/or fixtures to incorporate a glass shield that brings the UV emissions down to a negligible level. For example, an MR16 with a cover glass takes over 30 times as long to emit the same amount of UV as an MR16 without a cover glass.

Source: http://www.elflist.com
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