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IR filter????

Seldovia

Seldovia

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Today my borrowed green laser pointer stopped shining green light when I pressed the button for a few minutes. So I took this as a time to check for an IR filter since there wasn't any green light coming out. I took a photo with my iPhone of the aperture.

Here's the photo:
5a4xlh.jpg


What does it look like to you? Is there an IR filter?
 





crazyspaz

crazyspaz

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Well if you can see the IR in the picture (you can), then it stands to reason it isn't being filtered out....I'm guessing its a cheap ebay pen, and those are never filtered anyway.
 
NightExplorer96

NightExplorer96

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Yes. As said by "crazyspaz" the red dot the camera is seeing is IR light which green lasers use to produce the 532nm wavelength.

Most cheap green lasers/eBay lasers omit these filters as it costs too much to add one on the unit.

Please do be careful around this laser :)
 
The Lightning Stalker

The Lightning Stalker

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Whatever you do, DO NOT look into the laser. The IR is far stronger than shows up in the picture.
iPhones have an IR filter and frankly I'm surprised anything showed up at all. If you have a Sony with Night
Shot, put it into Night Shot mode and you will get a better idea of just how much is coming out. It is
probably at least 20mW, more than enough to damage your eyesight.
 
supermario680

supermario680

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The Lightning Stalker said:
Which model? AFAIK, they have them front and back, at least they used to.
Click to expand...

Iphone 4s and I can assure you it does not have one on the front facing VGA camera.

regular main high res camera, notice the blue colored LED doesn't appear to be emitting any light.

35mfxis.jpg


vga camera without IR filter reveals the light that is invisible to the naked eye.

2wlsjkg.jpg
 
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Seldovia

Seldovia

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supermario680 said:
Could this be why it died? did your laser say anything about recommended duty cycles??

and IR light shows up blue on my iphone fyi... not sure about your pic though...
Click to expand...
When I say "pressed the button for a few minutes" I didn't mean it died completely. I mean it shuts off, and if you wait a little bit it turns on again. Also I am pretty sure this is way overpowered. It says <5mw, but I have a 5mw green, and this has to be at least 3 times brighter. The beam is extremely visible in the dark.
 
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The Lightning Stalker

The Lightning Stalker

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supermario680 said:
2wlsjkg.jpg
Click to expand...

Did you set all that up just to show us the IR capabilities of the iPhone 4s? If so, then +rep.
It's a shame the older ones have the filter, though. It would have made my life a bit easier.

Seldova: This happens because the nonlinear crystal in there gets a bit too warm. It also
happens when it gets too cold. The laser diode and Nd:YVO crystal don't have this problem,
so the infrared keeps on going. Actually they do, but they need more heat before anything
starts to happen; though once it gets that hot it's usually permanently damaged.
 
Seldovia

Seldovia

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The Lightning Stalker said:
Did you set all that up just to show us the IR capabilities of the iPhone 4s? If so, then +rep.
It's a shame the older ones have the filter, though. It would have made my life a bit easier.

Seldova: This happens because the nonlinear crystal in there gets a bit too warm. It also
happens when it gets too cold. The laser diode and Nd:YVO crystal don't have this problem,
so the infrared keeps on going. Actually they do, but they need more heat before anything
starts to happen; though once it gets that hot it's usually permanently damaged.
Click to expand...
"...gets too cold..."

That shouldn't be a problem considering I live dead smack in the middle of Alaska... :D
 
supermario680

supermario680

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The Lightning Stalker said:
Did you set all that up just to show us the IR capabilities of the iPhone 4s? If so, then +rep.
It's a shame the older ones have the filter, though. It would have made my life a bit easier.
Click to expand...

Lol. No, I've been playing with an arduino micro lately and just happened to have a pic of the IR emitter led I saved on my phone. Been playing with driving a cheap walmart lasers with it and experimenting and learning with transistors and IR emitter/detector led's and various sensors and relays just for fun. My iphone was the only thing in my house I had that could take an image of the IR light. I wanted to see what it would look like.
 
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