I don't know if you guys know anything about IR light and damaging human eyes, but any info would be appreciated!
Once I discovered that any digital camera, be it a webcam or smartphone, can see infrared light as purple/white (if you didn't know that, try it out! point your smart phone camera at your TV remote, its pretty cool!), I knew I had to make a high-power infrared flashlight so that I could use them as night vision devices, or night security cameras.
So I have a 3 watt, 1.6v infrared LED, and I'm driving it with a very simple current regulator circuit using an LM317T and a 1.5 ohm, 5 watt resistor. Even though this resistor configuration only runs the LED at 2.2 watts, (its all the LM317 can handle, even with the big heatsink I have on it), its still hella-bright. Most of my digital cameras still have IR filters over the lenses, and I can STILL light up a pitch black room with this LED.
Now I'm not stupid enough to stare directly into the LED while its on; it would be like looking at a high-power white LED with broken pupils that can't constrict. So because your brain doesn't see the IR light, the pupils don't shrink like they would when you look at a regular bright light, and you end up getting waaaay too many photons in your eye. Although I do briefly glance at the LED for a split second, just to see if its on, because it emits a dim visible red glow when it is on.
But I'm getting headaches every time I test this LED. I point it away from me, and I mostly look into the phone, but I am facing the same general direction as the reflected IR light that is bouncing off the walls and floors. Is even the reflected IR light likely enough to damage my eyes? Even if I only test the LED for 10 or 20 seconds and point it away from me, I get a mild headache that lasts for about 15 minutes, and mild eye pain that lasts for about an hour. You know that feeling when you wake up in the middle of the night, and turn on a really bright light and it hurts your eyes? It's like 10% of that for an hour.
I want to know if this is safe to use as a night-time illuminator for a front-door security camera, or would I be blinding everyone that walks past my house?
Once I discovered that any digital camera, be it a webcam or smartphone, can see infrared light as purple/white (if you didn't know that, try it out! point your smart phone camera at your TV remote, its pretty cool!), I knew I had to make a high-power infrared flashlight so that I could use them as night vision devices, or night security cameras.
So I have a 3 watt, 1.6v infrared LED, and I'm driving it with a very simple current regulator circuit using an LM317T and a 1.5 ohm, 5 watt resistor. Even though this resistor configuration only runs the LED at 2.2 watts, (its all the LM317 can handle, even with the big heatsink I have on it), its still hella-bright. Most of my digital cameras still have IR filters over the lenses, and I can STILL light up a pitch black room with this LED.
Now I'm not stupid enough to stare directly into the LED while its on; it would be like looking at a high-power white LED with broken pupils that can't constrict. So because your brain doesn't see the IR light, the pupils don't shrink like they would when you look at a regular bright light, and you end up getting waaaay too many photons in your eye. Although I do briefly glance at the LED for a split second, just to see if its on, because it emits a dim visible red glow when it is on.
But I'm getting headaches every time I test this LED. I point it away from me, and I mostly look into the phone, but I am facing the same general direction as the reflected IR light that is bouncing off the walls and floors. Is even the reflected IR light likely enough to damage my eyes? Even if I only test the LED for 10 or 20 seconds and point it away from me, I get a mild headache that lasts for about 15 minutes, and mild eye pain that lasts for about an hour. You know that feeling when you wake up in the middle of the night, and turn on a really bright light and it hurts your eyes? It's like 10% of that for an hour.
I want to know if this is safe to use as a night-time illuminator for a front-door security camera, or would I be blinding everyone that walks past my house?
