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Infrared LED array for heating?

  1. Oct 22, 2015 #1
    We have LED arrays for visible lighting. What problems exist for using infrared LED arrays as a heat source for humans, like those in a residential settings?

    Does effectiveness vary much by wavelength and skin color, clothing worn, etc?

    Thanks. :-)
  2. jcsd
  3. Oct 22, 2015 #2

    Simon Bridge

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    Welcome to PF;
    Short answer: "IR" and "heat" are not the same thing.
    A quick check shows that LED heat lamps are commercially available, have you tried investigating their designs to help you with your question?
  4. Oct 23, 2015 #3
    They do generate very useful and comfortable heat, and the beam can be focused with optics. I will soon get 10 full scale prototypes IR LED heating lamps - and I expect them to give some 5 C.

    The questions you ask are very relevant, but there has been very little if any research into this area.
  5. Oct 23, 2015 #4


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    Radiant heaters (sometimes called "direct heaters") tend to be directional. So they do a good job of warming up the part of your body that faces them but perhaps not the bit in shadow. For all round comfort you generally do better to heat the air in the room using conduction/convection.

    Radiant heaters have uses in car service workshops where it's too expensive to heat the air because the doors are opened regularly.
  6. Oct 23, 2015 #5
    I appreciate the encouragement. I quickly found a example of a hand held "pain relieving" ir wand with 72 LEDs. I have some ideas on this. Want to chat?
  7. Oct 24, 2015 #6


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    For producing IR, a standard filament lamp should work pretty well in most applications. I'm not sure why one would pay the extra cost of getting LEDs instead.
  8. Oct 24, 2015 #7


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    That's a good point. The thing that makes a filament lamp unattractive as a light source is that its spectrum is largely IR. Its efficiency as an IR heating source makes it less unattractive. I would be interested to know how the overall losses (including a LV power source) for an IR array would compare with a filament with its supply.
    There could be advantages for a LED as it could be more physically robust but I wonder about its operating temperature? You would be needing several tens of Watts and would the resulting temperature not be a problem.
  9. Oct 24, 2015 #8
    Sure. I have done a lot of work on this - but too much on my own. The core of my idea is to use the IR LED as a focused means of heating. This could result in major energy savings on space heating. You may also google MIT "local heating" for a similar project - although they may not be active at this the moment.

    How about your ideas?

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