I'm struggling a bit with this. I know LEDs are built using semiconductors, but a diode is a also a semiconductor right? So, Laser Diodes are not essentially the same as LEDs?


closed as too broad by Leon Heller, PeterJ, jippie, Daniel Grillo, Fizz Nov 11 '15 at 19:47

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  • \$\begingroup\$ Question can easily be answered with a Google search. It should be closed. \$\endgroup\$ – Leon Heller Nov 7 '15 at 16:53
  • \$\begingroup\$ And if you write out LED you end up with Light emitting Diode - wait what? They are both diodes? The difference is, one emits laser light (it has special properties) and the other does not. Of course they must be produced differently as well to be able to do that... \$\endgroup\$ – Arsenal Nov 7 '15 at 22:09
  • \$\begingroup\$ en.wikipedia.org/wiki/Laser_diode explains a lot. \$\endgroup\$ – Fizz Nov 11 '15 at 19:47
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    \$\begingroup\$ For more details you could look at matthiaspospiech.de/files/studium/praktikum/diodelasers.pdf \$\endgroup\$ – Fizz Nov 11 '15 at 19:53

Laser is an acronym for basically a light beam with a very small spread. Lasers come in a multitude of forms from chemical to electrical to gas. Not all are diodes, not all are semiconductors.

LEDs on the other hand are semiconductors, and are always diodes. Unlike most diodes, leds can't be run in reverse without precise amperage control.

Another big difference is the power. Most leds (with the exception of high output) are more efficient than their laser counterparts.


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