what are light emitting diodes?

Answer 1

Well, they are diodes which emit light when a current is passed though them. Overly basic? OK. A diode is a conductor which conducts electricity much better in one direction than in the other. Most diodes in use now consist of a junction between two types of transition metals. The way there electron lattices work at the point where they meet makes it much easier for electrons to migrate across the bounder in one direction than the other. That's the basic diode. Some types of intermediate conductors, when excited by this current being passed, will experience the electrons at this junction being excited to a higher energy level, and then dropping back down to their previous state. When they drop down, they emit a photon, thus the light.

Answer 2

I light to think of them this way:
a bottle-neck effect causes electrons to move slower to get into the diode, but since they are moving slower they have no need to draw more energy - they are moving.
At some point along their travel inside the diode they meet with a junction - a junction they cannot pass, so they are stopped right there. Suddenly, the next wave comes through and one electron smacks right into the first one stuck at the junction. At this precise moment energy is transferred from the second to the first and forces the first electron across the junction.
Once on the other side, a bottle-neck is facting it once again, it can only move so fast, which is a slower rate than it traveled to get here. Therefore this extra energy has to be eliminated since the electon cannot store and save energy for later use - it is given off in two ways, light and heat.

Answer 3

Light emitting diodes are commonly referred to as LED's. They are used in a multitude of applications. Most commonly, they are used as indicator lights in electronics becuase the use virtually no energy, allowing all the energy from the power service to go to the devices intended purpose.

Edited:
Wow, I've gotta give PoppaJ his props. He just put a weeks worth of lecture into a paragraph.

Answer 4

commonly called LEDs, are real unsung heroes in the electronics world. They do dozens of different jobs and are found in all kinds of devices. Among other things, they form the numbers on digital clocks, transmit information from remote controls, light up watches and tell you when your appliances are turned on. Collected together, they can form images on a jumbo television screen or illuminate a traffic light.

Basically, LEDs are just tiny light bulbs that fit easily into an electrical circuit. But unlike ordinary incandescent bulbs, they don't have a filament that will burn out, and they don't get especially hot. They are illuminated solely by the movement of electrons in a semiconductor material, and they last just as long as a standard transistor.

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Answer 5

they are called LEDs diodes. that emits light. eh.. for example, traffic lights uses LEDs. or when u boot up ur comp, something will b lighted up on ur CPU casing. tts LED. LED only consume very little power and emits very bright light. it got lots of colors and they are super cheap as well. when u build a circuit, or anything that involve with LEDs, please b reminded that LEDs must be in series with a resister. if not current will burn off ur LEDs instantly.

hope it helps. i study electronics. hehe..

Answer 6

these are the diodes which works on phenomenon of stimulated emission

Answer 7

LED.