what are LEDs used for?

Question

(light emitting diodes)

Answer 1

LED, is a semi-conductor diode that responds to the application of voltage by giving off light. Most are not bright enough to light up a room.

Early calculators used LED display before LCD (liquid crystal) is used now.

Common in flashlights now.

Used as indicator lamps and digital displays.

Answer 2

They're used to emit light. In things light signs, flashlights, electronic display panels and electronics. Most 'on' lights are LED's. The largest users of LED's are the auto companies, followed by the large electronic sign and ticker display companies, like Trans-Lux.

Answer 3

LEDs are used to emit light... you can use them in any application you need to emit light

Answer 4

They are used all over the place where a light is required.

Typical = the lights on the front of your computer

Comonly used on electroic equipment because they use much less power than ordinary light bulbs

Answer 5

There are many applications, from switch indications to torches/flashlights.

Some modern cars now use these for taillights. They are faster acting and do not blow like regular bulbs.

Answer 6

they are a small light usaully red that lights up when something is switched on, for example a tv screen when you switch it on you will see a led lit up

Answer 7

Some of these applications are further elaborated upon in the following text.

Architectural lighting
Status indicators on all sorts of equipment
Traffic lights and signals
Exit signs
Motorcycle and Bicycle lights
Toys and recreational sporting goods, such as the Flashflight
Railroad crossing signals
Continuity indicators
Flashlights. Some models that do not even use batteries are of this type.
Light bars on emergency vehicles.
Elevator Push Button Lighting
Thin, lightweight message displays at airports and railway stations and as destination displays for trains, buses, trams and ferries.
Red or yellow LEDs are used in indicator and alphanumeric displays in environments where night vision must be retained: aircraft cockpits, submarine and ship bridges, astronomy observatories, and in the field, e.g. night time animal watching and military field use.
Red, yellow, green, and blue LEDs can be used for model railroading applications
Remote controls, such as for TVs and VCRs, often use infrared LEDs.
In optical fiber and Free Space Optics communications.
In dot matrix arrangements for displaying messages.
Glowlights, as a more expensive but longer lasting and reusable alternative to Glowsticks.
Grow lights composed of LED's are more efficient, both because LEDs produce more lumens per watt than other alternatives, and also because they can be tuned to the specific wavelengths plants can make the most use of.
Movement sensors, for example in optical computer mice
Because of their long life and fast switching times, LEDs have been used for automotive high-mounted brake lights and truck and bus brake lights and turn signals for some time, but many high-end vehicles are now starting to use LEDs for their entire rear light clusters. Besides the gain in reliability, this has styling advantages because LEDs are capable of forming much thinner lights than incandescent lamps with parabolic reflectors. The significant improvement in the time taken to light up (perhaps 0.5s faster than an incandescent bulb) improves safety by giving drivers more time to react. It has been reported that at normal highway speeds this equals 1 car length increased reaction time for the the car behind.
Backlighting for LCD televisions and displays. The availability of LEDs in specific colors (RGB) enables a full-spectrum light source which expands the color gamut by as much as 45%.
New stage lighting equipment is being developed with LED sources in primary red-green-blue arrangements.
Lumalive, a photonic textile
LED-based Christmas lights have been available since 2002, but are only now beginning to gain in popularity and acceptance due to their higher initial purchase cost when compared to similar incandescent-based Christmas lights. For example, as of 2006, a set of 50 incandescent lights might cost $2.00 USD, while a similar set of 50 LED lights might cost $10.00 USD. The purchase cost can be even higher for single-color sets of LED lights with rare or recently-introduced colors, such as purple, pink or white. Regardless of the higher initial purchase price, the total cost of ownership for LED Christmas lights would eventually be lower than the TCO for similar incandescent Christmas lights since an LED requires much less power to output the same amount of light as a similar incandescent bulb.
LED phototherapy for acne using blue or red LEDs has been proven to significantly reduce acne over a 3 month period.[citation needed]
As a medium quality voltage reference in electronic circuits. The forward voltage drop (e.g. about 1.7 V for a normal red LED) can be used instead of a Zener diode in low-voltage regulators. Although LED forward voltage is much more current-dependent than a good Zener, Zener diodes are not available below voltages of about 3 V.
Computers, for hard drive activity and power on. Some custom computers feature LED accent lighting to draw attention to a given component. Macintosh computers use LEDs to tell the user that it is asleep, by fading in and out. This fading is produced by either a triangular wave or a sine wave generator

Answer 8

Zeppelins?

Answer 9

they stand for LIGHT EMMITTING DIODE [LED]