Using 3D glasses to view IR

I discovered 3 pretty cool things today using 3D glasses, my webcam, and a 50mw laser pointer. When wearing 3D glasses (and in my case, they were the special magenta + green glasses) and I closed my green side eye, I couldn't see any green, all I saw was a tiny amber/635nm colored spot. I'm assuming this was the IR. When shinning the laser through the magenta/red side, I could see a tiny green spec on paper (when using the naked eye). THEN when I shined it through the magenta/red, and looked at it through my webcam, I saw blue. Here's a pic of the blue:

View attachment IR GREEN.bmp

View attachment IR green2.bmp

wow you could totally use that as a cheap IR filter. but whats with the blue, maybe IR isnt the only problem anymore maybe UV is in on it too. lol.

iwannapony said:

wow you could totally use that as a cheap IR filter. but whats with the blue, maybe IR isnt the only problem anymore maybe UV is in on it too. lol.

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No there's definitely no UV in a green laser, you get leaked IR in some green pointers due to the IR pump diode, which pumps crystals to produce the green (532nm) light.

The web cam saw the dot as blue because it doesn't normally register invisible light correctly as there is no colour too it.

There is no UV light there, pure 532, 1064 and 808nm.
But some cameras see IR as blue.

EDIT :
Asherz was faster...

i was joking about the UV. yeah i know some cheap digital cameras see laser light as different colors, especially HP cameras and green lasers.

Yup, the blue was the IR. I wish I could show you the golednish color I get...

wear ur cam 3D glasses,and take a pic,thats will be funny,lol

The spot you saw that was, "635nm", in colour was not you seeing IR. You cannot see the IR. That is the point. If you happen to be able to register IR at all it will appear deep red, not golden. The point of 3D glasses is to filter out the green light on one side. This means that the light coming through that side is probably flourescense from the surface you were lasing. I repeat, you were not seeing IR! You were, however, exposing yourself to just the IR though. Not very sensible at all. At least when the green light is there the iris closes a little and your blink reflex has a chance of protecting your eye from reflections. Not the case when viewing IR through the magenta/red.

This is not safe to do. Please do not encourage others to try it.

M

Oh...woops...I didn't know that, however there wasn't anything on it, so I'm sorry.

The red side of the 3d glasses might block the green light like laser safety goggles do. A green dot looks orange-ish red through the proper goggles. What you were seeing was defiantly not IR though.

If that is the case, then what you are seeing on the webcam is leaked IR from the laser. The red lens blocks most of the green and the IR passes through, which the camera picks up.

That is a good way to test for a IR filter, but higher powered green lasers will melt the red lens before you can get any good reading. This is really only good for low powered lasers.

The blue lens side might block the IR light, try shining the laser through both at the same time and see if the webcam picks anything up.

Pontiacg5 said:

higher powered green lasers will melt the red lens before you can get any good reading. This is really only good for low powered lasers.

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Anyone reading this thread, please note that the red side of the 3d glasses that 'blocks' 532nm is NOT to be used as a saftey device or to block any laser light from entering the eye, even with lower powered laser. These have no Optical density rating and is a thin piece of plastic, again do not use these as saftey glasses.

This has been a public service saftey annoucment