Why does an LED have to be a diode?

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I know LED stands for Light Emitting Diode; but why does this component need to be a diode to emit light?



My question assumes that the "leds" we see everywhere (for lighting, screens, etc) are actually diodes -- this assumption might be wrong.










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    – F.Ahmed
    3 hours ago






  • 1




    There were times the light sources were never LEDs. To your question: What is called LED is LED. If someone is calling LED something that is not a LED, they are wrong.
    – Eugene Sh.
    3 hours ago







  • 1




    It doesn't have to be an LED to emit light, however it does have to be a diode to be a light emitting diode.
    – Robert Fay
    3 hours ago






  • 2




    your question is a bit unclear .... it looks like you are asking something else .... you should simply ask Why does an LED have to be a diode?
    – jsotola
    3 hours ago






  • 2




    There are also light emitting capacitors (commonly called EL-wire) and light emitting resistors (commonly called incandescent light bulbs) and light-emitting vacuum tubes (commonly called CRTs) and light-emitting gas-discharge tubes (commonly called fluorescent lights) and...
    – Felthry
    2 hours ago














up vote
2
down vote

favorite












I know LED stands for Light Emitting Diode; but why does this component need to be a diode to emit light?



My question assumes that the "leds" we see everywhere (for lighting, screens, etc) are actually diodes -- this assumption might be wrong.










share|improve this question









New contributor




noamtm is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.















  • 2




    Welcome to EE.SE! Find out everything you need to get started by taking a 2-minute tour (electronics.stackexchange.com/tour).
    – F.Ahmed
    3 hours ago






  • 1




    There were times the light sources were never LEDs. To your question: What is called LED is LED. If someone is calling LED something that is not a LED, they are wrong.
    – Eugene Sh.
    3 hours ago







  • 1




    It doesn't have to be an LED to emit light, however it does have to be a diode to be a light emitting diode.
    – Robert Fay
    3 hours ago






  • 2




    your question is a bit unclear .... it looks like you are asking something else .... you should simply ask Why does an LED have to be a diode?
    – jsotola
    3 hours ago






  • 2




    There are also light emitting capacitors (commonly called EL-wire) and light emitting resistors (commonly called incandescent light bulbs) and light-emitting vacuum tubes (commonly called CRTs) and light-emitting gas-discharge tubes (commonly called fluorescent lights) and...
    – Felthry
    2 hours ago












up vote
2
down vote

favorite









up vote
2
down vote

favorite











I know LED stands for Light Emitting Diode; but why does this component need to be a diode to emit light?



My question assumes that the "leds" we see everywhere (for lighting, screens, etc) are actually diodes -- this assumption might be wrong.










share|improve this question









New contributor




noamtm is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
Check out our Code of Conduct.











I know LED stands for Light Emitting Diode; but why does this component need to be a diode to emit light?



My question assumes that the "leds" we see everywhere (for lighting, screens, etc) are actually diodes -- this assumption might be wrong.







led diodes light






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noamtm is a new contributor to this site. Take care in asking for clarification, commenting, and answering.
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share|improve this question









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edited 2 hours ago





















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asked 3 hours ago









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  • 2




    Welcome to EE.SE! Find out everything you need to get started by taking a 2-minute tour (electronics.stackexchange.com/tour).
    – F.Ahmed
    3 hours ago






  • 1




    There were times the light sources were never LEDs. To your question: What is called LED is LED. If someone is calling LED something that is not a LED, they are wrong.
    – Eugene Sh.
    3 hours ago







  • 1




    It doesn't have to be an LED to emit light, however it does have to be a diode to be a light emitting diode.
    – Robert Fay
    3 hours ago






  • 2




    your question is a bit unclear .... it looks like you are asking something else .... you should simply ask Why does an LED have to be a diode?
    – jsotola
    3 hours ago






  • 2




    There are also light emitting capacitors (commonly called EL-wire) and light emitting resistors (commonly called incandescent light bulbs) and light-emitting vacuum tubes (commonly called CRTs) and light-emitting gas-discharge tubes (commonly called fluorescent lights) and...
    – Felthry
    2 hours ago












  • 2




    Welcome to EE.SE! Find out everything you need to get started by taking a 2-minute tour (electronics.stackexchange.com/tour).
    – F.Ahmed
    3 hours ago






  • 1




    There were times the light sources were never LEDs. To your question: What is called LED is LED. If someone is calling LED something that is not a LED, they are wrong.
    – Eugene Sh.
    3 hours ago







  • 1




    It doesn't have to be an LED to emit light, however it does have to be a diode to be a light emitting diode.
    – Robert Fay
    3 hours ago






  • 2




    your question is a bit unclear .... it looks like you are asking something else .... you should simply ask Why does an LED have to be a diode?
    – jsotola
    3 hours ago






  • 2




    There are also light emitting capacitors (commonly called EL-wire) and light emitting resistors (commonly called incandescent light bulbs) and light-emitting vacuum tubes (commonly called CRTs) and light-emitting gas-discharge tubes (commonly called fluorescent lights) and...
    – Felthry
    2 hours ago







2




2




Welcome to EE.SE! Find out everything you need to get started by taking a 2-minute tour (electronics.stackexchange.com/tour).
– F.Ahmed
3 hours ago




Welcome to EE.SE! Find out everything you need to get started by taking a 2-minute tour (electronics.stackexchange.com/tour).
– F.Ahmed
3 hours ago




1




1




There were times the light sources were never LEDs. To your question: What is called LED is LED. If someone is calling LED something that is not a LED, they are wrong.
– Eugene Sh.
3 hours ago





There were times the light sources were never LEDs. To your question: What is called LED is LED. If someone is calling LED something that is not a LED, they are wrong.
– Eugene Sh.
3 hours ago





1




1




It doesn't have to be an LED to emit light, however it does have to be a diode to be a light emitting diode.
– Robert Fay
3 hours ago




It doesn't have to be an LED to emit light, however it does have to be a diode to be a light emitting diode.
– Robert Fay
3 hours ago




2




2




your question is a bit unclear .... it looks like you are asking something else .... you should simply ask Why does an LED have to be a diode?
– jsotola
3 hours ago




your question is a bit unclear .... it looks like you are asking something else .... you should simply ask Why does an LED have to be a diode?
– jsotola
3 hours ago




2




2




There are also light emitting capacitors (commonly called EL-wire) and light emitting resistors (commonly called incandescent light bulbs) and light-emitting vacuum tubes (commonly called CRTs) and light-emitting gas-discharge tubes (commonly called fluorescent lights) and...
– Felthry
2 hours ago




There are also light emitting capacitors (commonly called EL-wire) and light emitting resistors (commonly called incandescent light bulbs) and light-emitting vacuum tubes (commonly called CRTs) and light-emitting gas-discharge tubes (commonly called fluorescent lights) and...
– Felthry
2 hours ago










4 Answers
4






active

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votes

















up vote
3
down vote













The existing answers miss the core of the question.



An LED needs to be a diode, specifically because the way the charge carriers recombine in the forward-biased diode junction releases the correct amount of energy to create photons in the visible range. Passing a current through a chunk of semiconductor with no diode junction in it would simply produce heat.



Regular silicon diodes emit light, too, but because the band gap is too low, the photons emitted are in the infrared range, and invisible to the eye.






share|improve this answer



























    up vote
    2
    down vote













    A diode is the simplest semiconductor. And, the simplest semiconductor can also be made to emit light. Voila! Light emitting diode! One could potentially call it a light emitting semiconductor (LES), but that would just sound like a real name... sooo not cool.



    More complex semiconductors will have at least one diode at it's core. If one can make a semiconductor without a diode in it (I don't know how that's possible), and if it emits light, then one could potentially have a real LES that is not a LED!



    And yes, in a TV screen and everywhere else, if it is called an LED, the light (visible or invisible part of the spectrum) actually originates from the LED itself. It is the cheapest.






    share|improve this answer






















    • Is LES a typo? If it is then I don't see how can something which is not a diode be called a diode.
      – Eugene Sh.
      3 hours ago










    • It is always a diode. A diode is a semiconductor. So a light emitting diode is also a light emitting semiconductor. And for all practical purposes, a light emitting semiconductor is also a light emitting diode (unless you know of a non diode semiconductor that produces light).
      – Indraneel
      2 hours ago










    • OK, so LES is Light Emitting Semiconductor. That what I wanted to clarify.
      – Eugene Sh.
      2 hours ago










    • @EugeneSh. to clarify, "LES" is not a real (recognized) term. It is just something I came up with. To only me, it is an acronym for Light Emitting Semiconductor. There is no such thing sold in the market by that name.
      – Indraneel
      2 hours ago










    • A diode is a semiconductor device, not a semiconductor.
      – Felthry
      2 hours ago

















    up vote
    0
    down vote














    why does this component need to be a diode to emit light?




    By conservation of energy, light emission implies power input. It is normal to deliver electrical power through two wires, so
    the simplest electric powered light emitter has two wiring
    terminals, i.e. is a diode.



    Two-terminal semiconductors
    replaced two-terminal tubes (vacuum or gas-filled)
    having two electrodes, which were called 'diode', and the name
    has stuck. Electroluminescent panels of yesteryear were also semiconductors
    that gave off light, but weren't produced in the kinds of
    high-tech assembly lines that electronic diodes are made in.
    So, those weren't called diodes.



    White "LED" devices around you are not simple semiconductor
    diodes, but are structures with diodes and phosphors that give
    off useful amounts of white light, having a blue-emitting diode
    and red/orange/yellow/green phosphors that convert the blue light.
    Lenses and other features for effective light emission
    are common; LEDs do not resemble other practical diodes, except
    that they have two wires or connecting terminals.






    share|improve this answer




















    • Light emitting electroluminescent solid state devices were, ALWAYS called diodes when it was noticed the first experimental diodes emitted light in 1907. LEDs today still have all the characteristics of a common diode.
      – Misunderstood
      25 mins ago

















    up vote
    0
    down vote














    LED stands for Light Emitting Diode; but why does this component need
    to be a diode to emit light?




    Because LEDs are a diode which posses the same characteristics a common solid state diode.





    My question assumes that the "leds" we see everywhere (for lighting,
    screens, etc) are actually diodes -- this assumption might be wrong.




    Your assumption is correct.




    A diode is an electronic component that has low resistance in one direction. It is a dual electrode (anode and cathode) device where electron flow from cathode to anode is low conductance and the primary electron flow is the high conductance flow from anode to cathode.



    The most common diodes are made of crystallized semiconductor materials (e.g. silicone, germanium and gallium arsenide, indium phosphide, sapphire, and quartz) which are doped with p and n type impurities which are separated by the simplest semiconductor building block, the p-n junction.



    There are many types of diodes with various characteristics. It is the properties of the p and n dopants and their affect on the voltage-current characteristics of the p-n junction that separates one type of diode from another.



    The above applies to all diodes including LEDs.



    In LEDs the dopants have electroluminescence properties. When the electrons are crossing the p-n junction, many of the electrons are transformed into sub-atomic particles called photons.



    Light Emitting Diodes are called diodes because the are indeed semiconductor diodes that also emit photons in the form of UV, visible light, and IR.






    share|improve this answer






















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      4 Answers
      4






      active

      oldest

      votes








      4 Answers
      4






      active

      oldest

      votes









      active

      oldest

      votes






      active

      oldest

      votes








      up vote
      3
      down vote













      The existing answers miss the core of the question.



      An LED needs to be a diode, specifically because the way the charge carriers recombine in the forward-biased diode junction releases the correct amount of energy to create photons in the visible range. Passing a current through a chunk of semiconductor with no diode junction in it would simply produce heat.



      Regular silicon diodes emit light, too, but because the band gap is too low, the photons emitted are in the infrared range, and invisible to the eye.






      share|improve this answer
























        up vote
        3
        down vote













        The existing answers miss the core of the question.



        An LED needs to be a diode, specifically because the way the charge carriers recombine in the forward-biased diode junction releases the correct amount of energy to create photons in the visible range. Passing a current through a chunk of semiconductor with no diode junction in it would simply produce heat.



        Regular silicon diodes emit light, too, but because the band gap is too low, the photons emitted are in the infrared range, and invisible to the eye.






        share|improve this answer






















          up vote
          3
          down vote










          up vote
          3
          down vote









          The existing answers miss the core of the question.



          An LED needs to be a diode, specifically because the way the charge carriers recombine in the forward-biased diode junction releases the correct amount of energy to create photons in the visible range. Passing a current through a chunk of semiconductor with no diode junction in it would simply produce heat.



          Regular silicon diodes emit light, too, but because the band gap is too low, the photons emitted are in the infrared range, and invisible to the eye.






          share|improve this answer












          The existing answers miss the core of the question.



          An LED needs to be a diode, specifically because the way the charge carriers recombine in the forward-biased diode junction releases the correct amount of energy to create photons in the visible range. Passing a current through a chunk of semiconductor with no diode junction in it would simply produce heat.



          Regular silicon diodes emit light, too, but because the band gap is too low, the photons emitted are in the infrared range, and invisible to the eye.







          share|improve this answer












          share|improve this answer



          share|improve this answer










          answered 53 mins ago









          Dave Tweed♦

          112k9133242




          112k9133242






















              up vote
              2
              down vote













              A diode is the simplest semiconductor. And, the simplest semiconductor can also be made to emit light. Voila! Light emitting diode! One could potentially call it a light emitting semiconductor (LES), but that would just sound like a real name... sooo not cool.



              More complex semiconductors will have at least one diode at it's core. If one can make a semiconductor without a diode in it (I don't know how that's possible), and if it emits light, then one could potentially have a real LES that is not a LED!



              And yes, in a TV screen and everywhere else, if it is called an LED, the light (visible or invisible part of the spectrum) actually originates from the LED itself. It is the cheapest.






              share|improve this answer






















              • Is LES a typo? If it is then I don't see how can something which is not a diode be called a diode.
                – Eugene Sh.
                3 hours ago










              • It is always a diode. A diode is a semiconductor. So a light emitting diode is also a light emitting semiconductor. And for all practical purposes, a light emitting semiconductor is also a light emitting diode (unless you know of a non diode semiconductor that produces light).
                – Indraneel
                2 hours ago










              • OK, so LES is Light Emitting Semiconductor. That what I wanted to clarify.
                – Eugene Sh.
                2 hours ago










              • @EugeneSh. to clarify, "LES" is not a real (recognized) term. It is just something I came up with. To only me, it is an acronym for Light Emitting Semiconductor. There is no such thing sold in the market by that name.
                – Indraneel
                2 hours ago










              • A diode is a semiconductor device, not a semiconductor.
                – Felthry
                2 hours ago














              up vote
              2
              down vote













              A diode is the simplest semiconductor. And, the simplest semiconductor can also be made to emit light. Voila! Light emitting diode! One could potentially call it a light emitting semiconductor (LES), but that would just sound like a real name... sooo not cool.



              More complex semiconductors will have at least one diode at it's core. If one can make a semiconductor without a diode in it (I don't know how that's possible), and if it emits light, then one could potentially have a real LES that is not a LED!



              And yes, in a TV screen and everywhere else, if it is called an LED, the light (visible or invisible part of the spectrum) actually originates from the LED itself. It is the cheapest.






              share|improve this answer






















              • Is LES a typo? If it is then I don't see how can something which is not a diode be called a diode.
                – Eugene Sh.
                3 hours ago










              • It is always a diode. A diode is a semiconductor. So a light emitting diode is also a light emitting semiconductor. And for all practical purposes, a light emitting semiconductor is also a light emitting diode (unless you know of a non diode semiconductor that produces light).
                – Indraneel
                2 hours ago










              • OK, so LES is Light Emitting Semiconductor. That what I wanted to clarify.
                – Eugene Sh.
                2 hours ago










              • @EugeneSh. to clarify, "LES" is not a real (recognized) term. It is just something I came up with. To only me, it is an acronym for Light Emitting Semiconductor. There is no such thing sold in the market by that name.
                – Indraneel
                2 hours ago










              • A diode is a semiconductor device, not a semiconductor.
                – Felthry
                2 hours ago












              up vote
              2
              down vote










              up vote
              2
              down vote









              A diode is the simplest semiconductor. And, the simplest semiconductor can also be made to emit light. Voila! Light emitting diode! One could potentially call it a light emitting semiconductor (LES), but that would just sound like a real name... sooo not cool.



              More complex semiconductors will have at least one diode at it's core. If one can make a semiconductor without a diode in it (I don't know how that's possible), and if it emits light, then one could potentially have a real LES that is not a LED!



              And yes, in a TV screen and everywhere else, if it is called an LED, the light (visible or invisible part of the spectrum) actually originates from the LED itself. It is the cheapest.






              share|improve this answer














              A diode is the simplest semiconductor. And, the simplest semiconductor can also be made to emit light. Voila! Light emitting diode! One could potentially call it a light emitting semiconductor (LES), but that would just sound like a real name... sooo not cool.



              More complex semiconductors will have at least one diode at it's core. If one can make a semiconductor without a diode in it (I don't know how that's possible), and if it emits light, then one could potentially have a real LES that is not a LED!



              And yes, in a TV screen and everywhere else, if it is called an LED, the light (visible or invisible part of the spectrum) actually originates from the LED itself. It is the cheapest.







              share|improve this answer














              share|improve this answer



              share|improve this answer








              edited 3 hours ago

























              answered 3 hours ago









              Indraneel

              903411




              903411











              • Is LES a typo? If it is then I don't see how can something which is not a diode be called a diode.
                – Eugene Sh.
                3 hours ago










              • It is always a diode. A diode is a semiconductor. So a light emitting diode is also a light emitting semiconductor. And for all practical purposes, a light emitting semiconductor is also a light emitting diode (unless you know of a non diode semiconductor that produces light).
                – Indraneel
                2 hours ago










              • OK, so LES is Light Emitting Semiconductor. That what I wanted to clarify.
                – Eugene Sh.
                2 hours ago










              • @EugeneSh. to clarify, "LES" is not a real (recognized) term. It is just something I came up with. To only me, it is an acronym for Light Emitting Semiconductor. There is no such thing sold in the market by that name.
                – Indraneel
                2 hours ago










              • A diode is a semiconductor device, not a semiconductor.
                – Felthry
                2 hours ago
















              • Is LES a typo? If it is then I don't see how can something which is not a diode be called a diode.
                – Eugene Sh.
                3 hours ago










              • It is always a diode. A diode is a semiconductor. So a light emitting diode is also a light emitting semiconductor. And for all practical purposes, a light emitting semiconductor is also a light emitting diode (unless you know of a non diode semiconductor that produces light).
                – Indraneel
                2 hours ago










              • OK, so LES is Light Emitting Semiconductor. That what I wanted to clarify.
                – Eugene Sh.
                2 hours ago










              • @EugeneSh. to clarify, "LES" is not a real (recognized) term. It is just something I came up with. To only me, it is an acronym for Light Emitting Semiconductor. There is no such thing sold in the market by that name.
                – Indraneel
                2 hours ago










              • A diode is a semiconductor device, not a semiconductor.
                – Felthry
                2 hours ago















              Is LES a typo? If it is then I don't see how can something which is not a diode be called a diode.
              – Eugene Sh.
              3 hours ago




              Is LES a typo? If it is then I don't see how can something which is not a diode be called a diode.
              – Eugene Sh.
              3 hours ago












              It is always a diode. A diode is a semiconductor. So a light emitting diode is also a light emitting semiconductor. And for all practical purposes, a light emitting semiconductor is also a light emitting diode (unless you know of a non diode semiconductor that produces light).
              – Indraneel
              2 hours ago




              It is always a diode. A diode is a semiconductor. So a light emitting diode is also a light emitting semiconductor. And for all practical purposes, a light emitting semiconductor is also a light emitting diode (unless you know of a non diode semiconductor that produces light).
              – Indraneel
              2 hours ago












              OK, so LES is Light Emitting Semiconductor. That what I wanted to clarify.
              – Eugene Sh.
              2 hours ago




              OK, so LES is Light Emitting Semiconductor. That what I wanted to clarify.
              – Eugene Sh.
              2 hours ago












              @EugeneSh. to clarify, "LES" is not a real (recognized) term. It is just something I came up with. To only me, it is an acronym for Light Emitting Semiconductor. There is no such thing sold in the market by that name.
              – Indraneel
              2 hours ago




              @EugeneSh. to clarify, "LES" is not a real (recognized) term. It is just something I came up with. To only me, it is an acronym for Light Emitting Semiconductor. There is no such thing sold in the market by that name.
              – Indraneel
              2 hours ago












              A diode is a semiconductor device, not a semiconductor.
              – Felthry
              2 hours ago




              A diode is a semiconductor device, not a semiconductor.
              – Felthry
              2 hours ago










              up vote
              0
              down vote














              why does this component need to be a diode to emit light?




              By conservation of energy, light emission implies power input. It is normal to deliver electrical power through two wires, so
              the simplest electric powered light emitter has two wiring
              terminals, i.e. is a diode.



              Two-terminal semiconductors
              replaced two-terminal tubes (vacuum or gas-filled)
              having two electrodes, which were called 'diode', and the name
              has stuck. Electroluminescent panels of yesteryear were also semiconductors
              that gave off light, but weren't produced in the kinds of
              high-tech assembly lines that electronic diodes are made in.
              So, those weren't called diodes.



              White "LED" devices around you are not simple semiconductor
              diodes, but are structures with diodes and phosphors that give
              off useful amounts of white light, having a blue-emitting diode
              and red/orange/yellow/green phosphors that convert the blue light.
              Lenses and other features for effective light emission
              are common; LEDs do not resemble other practical diodes, except
              that they have two wires or connecting terminals.






              share|improve this answer




















              • Light emitting electroluminescent solid state devices were, ALWAYS called diodes when it was noticed the first experimental diodes emitted light in 1907. LEDs today still have all the characteristics of a common diode.
                – Misunderstood
                25 mins ago














              up vote
              0
              down vote














              why does this component need to be a diode to emit light?




              By conservation of energy, light emission implies power input. It is normal to deliver electrical power through two wires, so
              the simplest electric powered light emitter has two wiring
              terminals, i.e. is a diode.



              Two-terminal semiconductors
              replaced two-terminal tubes (vacuum or gas-filled)
              having two electrodes, which were called 'diode', and the name
              has stuck. Electroluminescent panels of yesteryear were also semiconductors
              that gave off light, but weren't produced in the kinds of
              high-tech assembly lines that electronic diodes are made in.
              So, those weren't called diodes.



              White "LED" devices around you are not simple semiconductor
              diodes, but are structures with diodes and phosphors that give
              off useful amounts of white light, having a blue-emitting diode
              and red/orange/yellow/green phosphors that convert the blue light.
              Lenses and other features for effective light emission
              are common; LEDs do not resemble other practical diodes, except
              that they have two wires or connecting terminals.






              share|improve this answer




















              • Light emitting electroluminescent solid state devices were, ALWAYS called diodes when it was noticed the first experimental diodes emitted light in 1907. LEDs today still have all the characteristics of a common diode.
                – Misunderstood
                25 mins ago












              up vote
              0
              down vote










              up vote
              0
              down vote










              why does this component need to be a diode to emit light?




              By conservation of energy, light emission implies power input. It is normal to deliver electrical power through two wires, so
              the simplest electric powered light emitter has two wiring
              terminals, i.e. is a diode.



              Two-terminal semiconductors
              replaced two-terminal tubes (vacuum or gas-filled)
              having two electrodes, which were called 'diode', and the name
              has stuck. Electroluminescent panels of yesteryear were also semiconductors
              that gave off light, but weren't produced in the kinds of
              high-tech assembly lines that electronic diodes are made in.
              So, those weren't called diodes.



              White "LED" devices around you are not simple semiconductor
              diodes, but are structures with diodes and phosphors that give
              off useful amounts of white light, having a blue-emitting diode
              and red/orange/yellow/green phosphors that convert the blue light.
              Lenses and other features for effective light emission
              are common; LEDs do not resemble other practical diodes, except
              that they have two wires or connecting terminals.






              share|improve this answer













              why does this component need to be a diode to emit light?




              By conservation of energy, light emission implies power input. It is normal to deliver electrical power through two wires, so
              the simplest electric powered light emitter has two wiring
              terminals, i.e. is a diode.



              Two-terminal semiconductors
              replaced two-terminal tubes (vacuum or gas-filled)
              having two electrodes, which were called 'diode', and the name
              has stuck. Electroluminescent panels of yesteryear were also semiconductors
              that gave off light, but weren't produced in the kinds of
              high-tech assembly lines that electronic diodes are made in.
              So, those weren't called diodes.



              White "LED" devices around you are not simple semiconductor
              diodes, but are structures with diodes and phosphors that give
              off useful amounts of white light, having a blue-emitting diode
              and red/orange/yellow/green phosphors that convert the blue light.
              Lenses and other features for effective light emission
              are common; LEDs do not resemble other practical diodes, except
              that they have two wires or connecting terminals.







              share|improve this answer












              share|improve this answer



              share|improve this answer










              answered 2 hours ago









              Whit3rd

              4,3651019




              4,3651019











              • Light emitting electroluminescent solid state devices were, ALWAYS called diodes when it was noticed the first experimental diodes emitted light in 1907. LEDs today still have all the characteristics of a common diode.
                – Misunderstood
                25 mins ago
















              • Light emitting electroluminescent solid state devices were, ALWAYS called diodes when it was noticed the first experimental diodes emitted light in 1907. LEDs today still have all the characteristics of a common diode.
                – Misunderstood
                25 mins ago















              Light emitting electroluminescent solid state devices were, ALWAYS called diodes when it was noticed the first experimental diodes emitted light in 1907. LEDs today still have all the characteristics of a common diode.
              – Misunderstood
              25 mins ago




              Light emitting electroluminescent solid state devices were, ALWAYS called diodes when it was noticed the first experimental diodes emitted light in 1907. LEDs today still have all the characteristics of a common diode.
              – Misunderstood
              25 mins ago










              up vote
              0
              down vote














              LED stands for Light Emitting Diode; but why does this component need
              to be a diode to emit light?




              Because LEDs are a diode which posses the same characteristics a common solid state diode.





              My question assumes that the "leds" we see everywhere (for lighting,
              screens, etc) are actually diodes -- this assumption might be wrong.




              Your assumption is correct.




              A diode is an electronic component that has low resistance in one direction. It is a dual electrode (anode and cathode) device where electron flow from cathode to anode is low conductance and the primary electron flow is the high conductance flow from anode to cathode.



              The most common diodes are made of crystallized semiconductor materials (e.g. silicone, germanium and gallium arsenide, indium phosphide, sapphire, and quartz) which are doped with p and n type impurities which are separated by the simplest semiconductor building block, the p-n junction.



              There are many types of diodes with various characteristics. It is the properties of the p and n dopants and their affect on the voltage-current characteristics of the p-n junction that separates one type of diode from another.



              The above applies to all diodes including LEDs.



              In LEDs the dopants have electroluminescence properties. When the electrons are crossing the p-n junction, many of the electrons are transformed into sub-atomic particles called photons.



              Light Emitting Diodes are called diodes because the are indeed semiconductor diodes that also emit photons in the form of UV, visible light, and IR.






              share|improve this answer


























                up vote
                0
                down vote














                LED stands for Light Emitting Diode; but why does this component need
                to be a diode to emit light?




                Because LEDs are a diode which posses the same characteristics a common solid state diode.





                My question assumes that the "leds" we see everywhere (for lighting,
                screens, etc) are actually diodes -- this assumption might be wrong.




                Your assumption is correct.




                A diode is an electronic component that has low resistance in one direction. It is a dual electrode (anode and cathode) device where electron flow from cathode to anode is low conductance and the primary electron flow is the high conductance flow from anode to cathode.



                The most common diodes are made of crystallized semiconductor materials (e.g. silicone, germanium and gallium arsenide, indium phosphide, sapphire, and quartz) which are doped with p and n type impurities which are separated by the simplest semiconductor building block, the p-n junction.



                There are many types of diodes with various characteristics. It is the properties of the p and n dopants and their affect on the voltage-current characteristics of the p-n junction that separates one type of diode from another.



                The above applies to all diodes including LEDs.



                In LEDs the dopants have electroluminescence properties. When the electrons are crossing the p-n junction, many of the electrons are transformed into sub-atomic particles called photons.



                Light Emitting Diodes are called diodes because the are indeed semiconductor diodes that also emit photons in the form of UV, visible light, and IR.






                share|improve this answer
























                  up vote
                  0
                  down vote










                  up vote
                  0
                  down vote










                  LED stands for Light Emitting Diode; but why does this component need
                  to be a diode to emit light?




                  Because LEDs are a diode which posses the same characteristics a common solid state diode.





                  My question assumes that the "leds" we see everywhere (for lighting,
                  screens, etc) are actually diodes -- this assumption might be wrong.




                  Your assumption is correct.




                  A diode is an electronic component that has low resistance in one direction. It is a dual electrode (anode and cathode) device where electron flow from cathode to anode is low conductance and the primary electron flow is the high conductance flow from anode to cathode.



                  The most common diodes are made of crystallized semiconductor materials (e.g. silicone, germanium and gallium arsenide, indium phosphide, sapphire, and quartz) which are doped with p and n type impurities which are separated by the simplest semiconductor building block, the p-n junction.



                  There are many types of diodes with various characteristics. It is the properties of the p and n dopants and their affect on the voltage-current characteristics of the p-n junction that separates one type of diode from another.



                  The above applies to all diodes including LEDs.



                  In LEDs the dopants have electroluminescence properties. When the electrons are crossing the p-n junction, many of the electrons are transformed into sub-atomic particles called photons.



                  Light Emitting Diodes are called diodes because the are indeed semiconductor diodes that also emit photons in the form of UV, visible light, and IR.






                  share|improve this answer















                  LED stands for Light Emitting Diode; but why does this component need
                  to be a diode to emit light?




                  Because LEDs are a diode which posses the same characteristics a common solid state diode.





                  My question assumes that the "leds" we see everywhere (for lighting,
                  screens, etc) are actually diodes -- this assumption might be wrong.




                  Your assumption is correct.




                  A diode is an electronic component that has low resistance in one direction. It is a dual electrode (anode and cathode) device where electron flow from cathode to anode is low conductance and the primary electron flow is the high conductance flow from anode to cathode.



                  The most common diodes are made of crystallized semiconductor materials (e.g. silicone, germanium and gallium arsenide, indium phosphide, sapphire, and quartz) which are doped with p and n type impurities which are separated by the simplest semiconductor building block, the p-n junction.



                  There are many types of diodes with various characteristics. It is the properties of the p and n dopants and their affect on the voltage-current characteristics of the p-n junction that separates one type of diode from another.



                  The above applies to all diodes including LEDs.



                  In LEDs the dopants have electroluminescence properties. When the electrons are crossing the p-n junction, many of the electrons are transformed into sub-atomic particles called photons.



                  Light Emitting Diodes are called diodes because the are indeed semiconductor diodes that also emit photons in the form of UV, visible light, and IR.







                  share|improve this answer














                  share|improve this answer



                  share|improve this answer








                  edited 15 mins ago

























                  answered 53 mins ago









                  Misunderstood

                  3,986516




                  3,986516




















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