LED's and Light Country: United States Date: March 2006 First
off I'm not sure if this should have been a question asked in
the computer section but here it goes. I know that light bulbs
produce light via heat. Tungsten filament, argon gas environment
so it does not ignite. Seems simple enough. LEDs (light emitting
diodes) give off light via an aluminum gallium arsenide semi-
conductor (I think). However, how exactly is electrical current
turned into light in LEDs? According to me physics and chemistry
teachers there is little to no heat given off, and technically
the light is not being "converted" to light. I am not sure what
they mean exactly. So how does an LED produce light? And why do
they never burn out? (unless of course you exceed the 50 mA
limit). What your teachers mean by "no heat given off" is that
LED's do not *radiate* infrared light, as light bulbs do. LED's
do give off heat. In fact, most of the energy that goes into an
led comes out as heat. Less than 20% is converted to light.
LED's give off