LED (Light Emiting Dioda), is a component can product of emissions light. LED findings after dioda. With the same structure also dioda, but later found that the electrons that run into the connection PN also release energy as heat energy and light energy. LED is made to be more efficient if the light issue. To produce light emissions in the semiconductor, doping is the use galium, arsenic and phosporus. A different type of doping will produce a different color of light also.
At this time the colors of LED that there is a lot of red, yellow and green. Basically, all colors can be produced, but it will be very expensive and inefficient.