Are infra red LEDs dangerous for the eyes?

Discussion in 'General Electronics Chat' started by rougie, Feb 2, 2013.

  1. rougie

    Thread Starter Active Member

    Dec 11, 2006
    410
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    Hello,

    I am using the TSAL6100 from Vishay
    and I was wondering how hazardous the
    ired coming out of this led is?

    I am using it at 1/3 it's power capacity and
    it will be used in homes as a beam breaker
    to turn on/off lamps.

    So it will most likely be shooting out IR for
    a couple of feet. Is this dangerous for the eyes?

    anyone has experience with IRed LEDs
    concerning this aspect.

    thanks
     
  2. antonv

    Member

    Nov 27, 2012
    149
    27
    It is safe, look around on Google. IR is long wave length low energy radiation.

    It will shoot out more than a couple of feet.
     
  3. thatoneguy

    AAC Fanatic!

    Feb 19, 2009
    6,357
    718
    That is an 80mW LED, so imagine a bright 5mm white LED brightness and that would be roughly the same output to your eye, not blinding, but not visible.

    Remote controls run that power of LED, I'm not aware of anybody suffering vision impairment from a remote. If this is something you'll be staring at for hours, it may be something to consider, but unlikely. I'm basing this on the fact that "Night View" IR Illuminators for cameras and non-FLIR night vision use several watts of IR light, and they do not have any sort of warning on them. :)

    --ETA: Here is a more official source: OSRAM App Note on IR and Eye Safety, attached PDF.
     
  4. Metalmann

    Active Member

    Dec 8, 2012
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    "I am using it at 1/3 it's power capacity and
    it will be used in homes as a beam breaker
    to turn on/off lamps."




    Something I'd mention, is where the sensors are mounted. Will they be close enough to the floor, where a baby may crawl up and stare into them?:confused:

    Inquisitive little kids may get a kick out of staring into them??:D



    Edited to add, a few weeks ago I was temporarily blinded, when an LED moved around and I looked directly at it. Saw white spots for 3 hrs.
     
  5. crutschow

    Expert

    Mar 14, 2008
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    What type and power of LED?
     
  6. rougie

    Thread Starter Active Member

    Dec 11, 2006
    410
    2
    yes. but that sensor can be disabled by the user if he or she
    wishes to. But can someone answer me this, is the Ir light
    that comes out of the led an inch away a lot more concentrated
    then the ir 3 feet away? Or is it th same 1" or 3 feet away?

    Aslo what worries me is what Vishay says in their safety document
    see here.... under "classification"

    http://www.vishay.com/ir-emitting-diodes/list/product-81009/

    Then click on the the following link:

    Eye Safety - Eye Safety Risk Assessment of Light or Infrared Emitting Diodes


    r
    Sent from my iPhone
     
    Last edited: Feb 2, 2013
  7. WBahn

    Moderator

    Mar 31, 2012
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    Yes, the intensity is greater as you get closer to the source. In general, it falls off proportional to the square of the distance.
     
  8. SPQR

    Member

    Nov 4, 2011
    379
    48
    The key to retinal damage is the ability of the lens to focus that particular wavelength on the retina.

    Near infrared is bent by the lens just like regular light, so it can damage the retina.

    The LED in question has peak power at 940 nm which is in the near infrared (close to visible light), and thus can damage the retina.

    As you know, human biology doesn't really have many "cut points" so there would be a "range" of wavelenghts that would be damaging, but the longer the wavelength the lower the probabilit of damage.

    For the chronicles, I'll add this table from Wiki:

    Near IR = 750-1400 nm
    SWIR = 1400-3000 nm
    MidIR = 3000-8000 nm
    LongIR = 8000-15000 nm
    FarIR = 15000-1000000 nm
     
  9. Metalmann

    Active Member

    Dec 8, 2012
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    Last edited: Feb 3, 2013
  10. rougie

    Thread Starter Active Member

    Dec 11, 2006
    410
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    an yes... I remember .... But one thing I am curious though
    is, if my led shots ir light a couple of feet and bounces off
    a wall, does it continue to fall off proportional to the
    square of the distance after it bounced off the wall?


    I will not be using any lense to concentrate the ir light,
    as I may simply put some sort of decorative plastic reflector
    over the led.


     
  11. crutschow

    Expert

    Mar 14, 2008
    13,001
    3,229
    It's unlikely that a standard IR LED outputs enough power to damage the eye. An IR laser LED is a different story since they typically have much higher output power, and those could possibly damage the eye.
     
  12. SPQR

    Member

    Nov 4, 2011
    379
    48
    There is probably so little power, the light would not "bounce" off of anything other than a mirror.

    No, damage would be a function of two things - frequency and power.
    Your LED is in the right frequency range for possible damage, but I doubt that it has near enough power.


    Hopefully, you're not staring into the sun for any significant period of time.
     
  13. rougie

    Thread Starter Active Member

    Dec 11, 2006
    410
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    okay thanks for the feedback !
    r
     
  14. rougie

    Thread Starter Active Member

    Dec 11, 2006
    410
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    One more thing...

    On the market, they sell small concentrator lenses that can concentrate infra red light.

    If I use a concentrator lense to concentrate the infra red light coming out of the led to a specific point, would this make my led infrared led more dangerous to the eyes if someone stares right into the LED ??

    r
     
  15. WBahn

    Moderator

    Mar 31, 2012
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    Yes, but "more dangerous" is a relative term. It is doubtful that you could concentrate it enough to be a problem. As long as you are dealing with output powers comparable to normal visible LEDs, you are unlikely to be able to make it dangerous even if you really tried. Not saying it's impossible, but I think you would really have to work at it. If that weren't the case, then you would see tons and tons of regulations governing everything that even thought of using an IR LED.
     
  16. rougie

    Thread Starter Active Member

    Dec 11, 2006
    410
    2
    Okay thanks WBahn...

    r
     
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