eye damage with IR LED'S?

Discussion in 'General Electronics Chat' started by lotusmoon, Jul 17, 2014.

  1. lotusmoon

    Thread Starter Member

    Jun 14, 2013
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    Is there any documentation on eye damage from IR LED'S.
    Can this damage the eyes if they are closed?
    I am thinking of at fairly low levels - LED's running at about 30 mw
     
  2. wayneh

    Expert

    Sep 9, 2010
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    Our eyes are fairly well evolved to handled IR, for instance as we stare into a campfire for hours at night. Most IR wavelengths of IR are absorbed by water, so our limits probably have something to do with maintaining temperature inside our eyes. Too much IR and they get hot and hurt like hades. I don't think your eyelids would pass enough IR to damage your eye without being painfully hot themselves.

    What frequency or wavelength are we talking about? Of course UV is a completely different matter.
     
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  3. crutschow

    Expert

    Mar 14, 2008
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    Yes, depending upon the wave-length and power density, IR laser light can damage the eye without you being aware of it. 30mW can create a high energy density when concentrated into a small spot. Read this for more info.
     
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  4. bertus

    Administrator

    Apr 5, 2008
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  5. alfacliff

    Well-Known Member

    Dec 13, 2013
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    I have worked on infra red lasers at power levels ove 1kw, those WILL damage your eyes. the only damage to my eyes so far, has beenfrom a low powered HeNe laser in a video disk player, I got a reflection off a screwdriver blade in my right eye, and now have some permanant " floaters" in that eye.
     
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  6. Metalmann

    Active Member

    Dec 8, 2012
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    When I was a kid, I stick welded on an old truck, for several hours without using a hood.:rolleyes:

    3rd degree burns, and blisters on both eyes, some of the most horrendous pain, on the Planet.
    Patches on both eyes for 3 weeks.

    You'd think I had learned my lesson.:D

    I do know for a fact, that the 1-100 Watt, white LEDs; will leave you temporarily blinded.
    That's only with a momentary glance.:eek:
    For several hours.
     
  7. Markd77

    Senior Member

    Sep 7, 2009
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    Welding gives off lots of UV, so you got bad sunburn.
    If you are talking about a normal unfocussed IR LED running at about 20mA and you aren't planning to put it continuously within a few inches of your eye, it isn't going to do any harm.
     
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  8. wayneh

    Expert

    Sep 9, 2010
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    That's what I assumed we were talking about, not lasers or focused beams.
     
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  9. crutschow

    Expert

    Mar 14, 2008
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    Yes, I was thinking 30mW output not input power. An IR LED running at 20mA should not cause harm unless perhaps help close to the eye for extended periods.
     
  10. lotusmoon

    Thread Starter Member

    Jun 14, 2013
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    Thank you for you info. to be clear I am not using lasers here. it is LED's.
     
  11. THE_RB

    AAC Fanatic!

    Feb 11, 2008
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    Some of the new high intensity LEDs are pretty scary!

    I had a brief flash from a 5mm blue LED running at 20mA, and could not see out of that eye for a few seconds. I think it was a 10000 mCd LED.

    Considering you might not notice the IR, an IR LED of the same intensity could conceivably cause eye damage if looking at it for some time. I'm sure the blue LED would.
     
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  12. wayneh

    Expert

    Sep 9, 2010
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    You were "on axis" for a focused beam? Those things are indeed crazy, painfully bright. I usually run them down at 5mA or so. Off-axis, not so bright.
     
  13. RichardO

    Well-Known Member

    May 4, 2013
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    Both IR and UV LED's and Lasers are especially dangerous because there is no natural blink reflex to the invisible light. If I remember correctly, the FDA has extra safety rules for IR and UV light sources because of this.
     
  14. THE_RB

    AAC Fanatic!

    Feb 11, 2008
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    Yeah it was one of the narrow beam angle ones, and I was looking right at it. :(

    For indicator use they are clearly visible even at 0.1mA.
     
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