There are several types of lights on the market today. One of these types is the LED light.
LED stands for "light-emitting diode" It is a semiconductor diode that emits a single wavelength of light when charged with an electric current. LEDs have many practical applications, and the technology is expanding to include organic light emitting diodes (OLEDs), which have significant potential for use in space lighting.
Typical Uses for LED Lighting
LEDs are commonly used in a wide array of electronic devices such as digital clocks, computer displays, optical mice and laser printers. They are also used in traffic lights and flashlights.
LEDs are being used more frequently in homes for landscape lighting, reading lamps, night lights and recessed light fixtures. With their increasing popularity, LED lights are now available with bases that fit inside standard lamp fixtures.
Most LEDs are made from aluminum, gallium and arsenide to which impurities have been added. The impurities create free electrons to help the semiconductor material conduct electricity.
The type of impurity used determines the color of the LED light. These colors can include green, blue, amber or red.
LED lights are often very small and use less energy than incandescent lights. They are also far less likely to burn out.
LED devices such as television sets and monitors last longer than comparable LCD devices. For space lighting, LED lights are an eco-friendly choice.
They use less electricity and produce less heat than incandescent bulbs. Unlike fluorescent lights, LEDs contain no mercury.
Plus, since they're encased in plastic, they're not as easily damaged as other light sources.
LED lights are expensive in comparison to incandescent and fluorescent light sources. When choosing LEDs for your lighting needs, you have to weigh the upfront cost of the device against the savings over the long term.
For example, a pack of 100 LED Christmas lights can cost more than twice what ordinary filament lights cost. You will need 5 to 8 of these strands to cover the average Christmas tree.
If you don't put your tree up early in the season and leave it on night and day for several weeks, you might not save enough on your electric bill to justify the expense. An LED television set or computer monitor will probably use less power and have a better picture quality than CRT equivalents.
However, an LED-backlit LCD TV or monitor will most likely be less expensive and have similar benefits to LED-only products. For space lighting, LEDs can be a very expensive option.
Also, LED lights give off directional light which is very blue in color, which limits their usefulness.
Future Potential of OLEDs
Organic light emitting diodes are self-luminous. Like LEDs, they glow when exposed to an electrical field.
However, they are usually paper-thin, use less power and are more flexible than regular LEDs. They are often applied to plastic film.
OLEDs are being used more frequently in camera displays and in "electronic paper" devices. OLED displays have better brightness and contrast than LCD displays.
Unlike LCD, they don't require any back-lighting. OLEDs are capable of producing diffuse, soft light and can light up surfaces such as walls or tables.
In the future, OLED devices will become available for residential space lighting, although it may be a while before they become affordable for the average homeowner.